Browsing by Author "Cose, Stephen"
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Item Anemia in Ugandan pregnant women: a cross-sectional, systematic review and meta-analysis study(Tropical medicine and health, 2021) Bongomin, Felix; Olum, Ronald; Kyazze, Andrew Peter; Ninsiima, Sandra; Nattabi, Gloria; Nakyagaba, Lourita; Nabakka, Winnie; Kukunda, Rebecca; Ssekamatte, Phillip; Kibirige, Davis; Cose, Stephen; Nakimuli, AnnetteeAnemia in pregnancy represents a global public health concern due to wide ranging maternal and neonatal adverse outcomes in all peripartum periods. We estimated the prevalence and factors associated with anemia in pregnancy at a national obstetrics and gynecology referral hospital in Uganda and in addition performed a systematic review and meta-analysis of the overall burden of anemia in pregnancy in Uganda. Methods: We conducted a cross-sectional study among 263 pregnant women attending the antenatal care clinic of Kawempe National Referral Hospital, Kampala, Uganda, in September 2020. Anemia in pregnancy was defined as a hemoglobin level of < 11.0 g/dl and microcytosis as a mean corpuscular volume (MCV) of < 76 fL. We also performed a systematic review (PROSPERO Registration ID: CRD42020213001) and meta-analysis of studies indexed on MEDLINE, Embase, African Journal Online, ClinicalTrials.gov, ICTRP, and the Cochrane Library of systematic review between 1 January 2000 and 31 September 2020 reporting on the prevalence of anemia in pregnancy in Uganda. Results: The prevalence of anemia was 14.1% (n= 37) (95%CI 10.4–18.8), of whom 21 (56.8%) had microcytic anemia. All cases of anemia occurred in the second or third trimester of pregnancy and none were severe. However, women with anemia had significantly lower MCV (75.1 vs. 80.2 fL, p<0.0001) and anthropometric measurements, such as weight (63.3 vs. 68.9kg; p=0.008), body mass index (25.2 vs. 27.3, p=0.013), hip (98.5 vs. 103.8 cm, p=0.002), and waist (91.1 vs. 95.1 cm, p=0.027) circumferences and mean systolic blood pressure (BP) (118 vs 125 mmHg, p=0.014). Additionally, most had BP within the normal range (59.5% vs. 34.1%, p=0.023). The comparison meta-analysis of pooled data from 17 published studies of anemia in pregnancy in Uganda, which had a total of 14,410 pregnant mothers, revealed a prevalence of 30% (95% CI 23–37). Conclusions: Despite our study having a lower prevalence compared to other studies in Uganda, these findings further confirm that anemia in pregnancy is still of public health significance and is likely to have nutritional causes, requiring targeted interventions. A larger study would be necessary to demonstrate potential use of basic clinical parameters such as weight or blood pressure as screening predictors for anemia in pregnancy.Item Antibody Responses to Schistosoma Mansoni Schistosomula Antigens(Parasite immunology, 2018) Egesa, Moses; Lubyayi, Lawrence; Jones, Frances M.; Tukahebwa, Edridah M.; Bagaya, Bernard S.; Dunne, David W.; Elliott, Alison M.; Wilson, Shona; Cose, StephenWhile antigens from Schistosoma schistosomula have been suggested as potential vaccine candidates, the association between antibody responses with schistosomula antigens and infection intensity at reinfection is not well known. Schistosoma mansoni-infected individuals were recruited from a schistosomiasis endemic area in Uganda (n = 372), treated with 40 mg/kg praziquantel (PZQ) and followed up at five weeks and at one year post-treatment. Pre-treatment and five weeks post-treatment immunoglobulin (Ig) E, IgG1 and IgG4 levels against recombinant schistosomula antigens rSmKK7, rSmLy6A, rSmLy6B and rSmTSP7 were measured using ELISA. Factors associated with detectable pre-treatment or post-treatment antibody response against the schistosomula antigens and the association between five-week antibody responses and one year post-treatment reinfection intensity among antibody responders were examined. Being male was associated with higher pre-treatment IgG1 to rSmKK7, rSmLy6a and AWA. Five weeks post-treatment antibody responses against schistosomula antigens were not associated with one year post-treatment reinfection intensity among antibody responders’ antibody levels against rSmKK7, rSmLy6B and rSmTSP7 dropped, but increased against rSmLy6A, AWA and SEA at five weeks post-treatment among antibody responders. S. mansoni-infected individuals exhibit detectable antibody responses to schistosomula antigens that are affected by treatment. These findings indicate that schistosomula antigens induce highly varied antibody responses and could have implications for vaccine development.Item Association between malaria exposure and Kaposi’s sarcoma-associated herpes virus seropositivity in Uganda(Tropical medicine & international health, 2015) Nalwoga, Angela; Cose, Stephen; Wakeham, Katie; Miley, Wendell; Ndibazza, Juliet; Drakeley, Christopher; Elliott, Alison; Whitby, Denise; Newton, RobertUnlike other herpes viruses, Kaposi’s sarcoma-associated herpes virus (KSHV) is not ubiquitous worldwide and is most prevalent in sub-Saharan Africa. The reasons for this are unclear. As part of a wider investigation of factors that facilitate transmission in Uganda, a high prevalence country, we examined the association between antimalaria antibodies and seropositivity against KSHV. Antibodies against P. falciparum merozoite surface protein (PfMSP)-1, P. falciparumapical membrane antigen (PfAMA)-1 and KSHV antigens (ORF73 and K8.1) were measured in samples from 1164 mothers and 1227 children. results Kaposi’s sarcoma-associated herpes virus seroprevalence was 69% among mothers and 15% children. Among mothers, KSHV seroprevalence increased with malaria antibody titres: from 60% to 82% and from 54% to 77%, comparing those with the lowest and highest titres for PfMSP- 1 and PfAMA-1, respectively (P < 0.0001). Among children, only antibodies to PfAMA-1 were significantly associated with KSHV seropositivity, (P < 0.0001). In both mothers and children, anti- ORF73 antibodies were more strongly associated with malaria antibodies than anti-K8.1 antibodies. conclusion The association between malaria exposure and KSHV seropositivity suggests that malaria is a cofactor for KSHV infection or reactivation.Item BCG-Induced Non-specific Effects on Heterologous Infectious Disease in Ugandan Neonates: an Investigator-blind Randomised Controlled trial(The Lancet Infectious Diseases, 2021) Prentice, Sarah; Nassanga, Beatrice; Webb, Emily L.; Akello, Florence; Kiwudhu, Fred; Akurut, Hellen; Elliott, Alison M.; Cose, StephenTrials done in infants with low birthweight in west Africa suggest that BCG vaccination reduces all-cause mortality in the neonatal period, probably because of heterologous protection against non-tuberculous infections. This study investigated whether BCG alters all-cause infectious disease morbidity in healthy infants in a different high-mortality setting, and explored whether the changes are mediated via trained innate immunity. This was an investigator-blind, randomised, controlled trial done at one hospital in Entebbe, Uganda. Infants who were born unwell (ie, those who were not well enough to be discharged directly home from the labour ward because they required medical intervention), with major congenital malformations, to mothers with HIV, into families with known or suspected tuberculosis, or for whom cord blood samples could not be taken, were excluded from the study. Any other infant well enough to be discharged directly from the labour ward was eligible for inclusion, with no limitation on gestational age or birthweight. Participants were recruited at birth and randomly assigned (1:1) to receive standard dose BCG 1331 (BCG-Danish) on the day of birth or at age 6 weeks (computer-generated randomisation, block sizes of 24, stratified by sex). Investigators and clinicians were masked to group assignment; parents were not masked. Participants were clinically followed up to age 10 weeks and contributed blood samples to one of three immunological substudies. The primary clinical outcome was physician-diagnosed non-tuberculous infectious disease incidence. Primary immunological outcomes were histone trimethylation at the promoter region of TNF, IL6, and IL1B; ex-vivo production of TNF, IL-6, IL-1β, IL-10, and IFNγ after heterologous stimulation; and transferrin saturation and hepcidin levels. All outcomes were analysed in the modified intention-to-treat population of all randomly assigned participants except those whose for whom consent was withdrawn. This trial is registered with the International Standard Randomised Controlled Trial Number registry (#59683017). Between Sept 25, 2014, and July 31, 2015, 560 participants were enrolled and randomly assigned to receive BCG at birth (n=280) or age 6 weeks (n=280). 12 participants assigned to receive BCG at birth and 11 participants assigned to receive BCG at age 6 weeks were withdrawn from the study by their parents shortly after randomisation and were not included in analyses. During the first 6 weeks of life before the infants in the delayed vaccination group received BCG vaccination, physician-diagnosed non-tuberculous infectious disease incidence was lower in infants in the BCG at birth group than in the delayed group (98 presentations in the BCG at birth group vs 129 in the delayed BCG group; hazard ratio [HR] 0·71 [95% CI 0·53–0·95], p=0·023). After BCG in the delayed group (ie, during the age 6–10 weeks follow-up), there was no significant difference in non-tuberculous infectious disease incidence between the groups (88 presentations vs 76 presentations; HR 1·10 [0·87–1·40], p=0·62). BCG at birth inhibited the increase in histone trimethylation at the TNF promoter in peripheral blood mononuclear cells occurring in the first 6 weeks of life. H3K4me3 geometric mean fold-increases were 3·1 times lower at the TNF promoter (p=0·018), 2·5 times lower at the IL6 promoter (p=0·20), and 3·1 times lower at the IL1B promoter (p=0·082) and H3K9me3 geometric mean fold-increases were 8·9 times lower at the TNF promoter (p=0·0046), 1·2 times lower at the IL6 promoter (p=0·75), and 4·6 times lower at the IL1B promoter (p=0·068), in BCG-vaccinated (BCG at birth group) versus BCG-naive (delayed BCG group) infants. No clear effect of BCG on ex-vivo production of TNF, IL-6, IL-1β, IL-10, and IFNγ after heterologous stimulation, or transferrin saturation and hepcidin concentration, was detected (geometric mean ratios between 0·68 and 1·68; p≥0·038 for all comparisons). BCG vaccination protects against non-tuberculous infectious disease during the neonatal period, in addition to having tuberculosis-specific effects. Prioritisation of BCG on the first day of life in high-mortality settings might have significant public-health benefits through reductions in all-cause infectious morbidity and mortality.Item Continuous research monitoring improves the quality of research conduct and compliance among research trainees: internal evaluation of a monitoring programme(AAS Open Research, 2020) Akello, Mirriam; Coutinho, Sarah; N-Mboowa, Mary Gorrethy; Bukirwa, Victoria D; Natukunda, Agnes; Lubyayi, Lawrence; Nabakooza, Grace; Cose, Stephen; Elliott, Alison M.Background: Research site monitoring (RSM) is an effective way to ensure compliance with Good Clinical Practice (GCP). However, RSM is not offered to trainees (investigators) at African Institutions routinely. The Makerere University/Uganda Virus Research Institute Centre of Excellence in Infection and Immunity Research and Training (MUIIPlus) introduced internal monitoring to promote the quality of trainees’ research projects. Here, we share our monitoring model, experiences and achievements, and challenges encountered. Methods: We analysed investigators’ project reports from monitoring visits undertaken from April 2017 to December 2019. Monitors followed a standard checklist to review investigator site files and record forms, and toured site facilities. We planned four monitoring visits for each trainee: one at site initiation, two interim, and a closeout monitoring visit. A team of two monitors conducted the visits. Results: We monitored 25 out of the 26 research projects in progress between April 2017 and December 2019. Compliance with protocols, standard operating procedures, GCP, and GCLP improved with each monitoring visit and all projects achieved 100% compliance at site closeout. All investigators had good work ethics and practice, and appropriate facilities. Initially, some investigators’ files lacked essential documents, and informed consent processes needed to be improved. We realized that non-compliant investigators had not received prior training in GCP/GCLP, so we offered them this training. Conclusions: Routine monitoring helps identify non-compliance early and improves the quality of research. We recommend continuous internal monitoring for all research studies. Investigators conducting research involving human subjects should receive GCP/GCLP training before commencing their projects. Institutional higher degrees and research ethics committees should enforce this as a requirement for project approvals.Item Contrasting Impact of Rural, Versus Urban, Living on Glucose Metabolism and Blood Pressure in Uganda(Wellcome open research, 2020) Sanya, Richard E.; Biraro, Irene Andia; Nampijja, Margaret; Zziwa, Christopher; Nanyunja, Carol; Nsubuga, Denis; Kiwanuka, Samuel; Tumusiime, Josephine; Walusimbi, Bridgious; Cose, Stephen; Ocama, Ponsiano; Grencis, Richard K.; Elliott, Alison M.; Webb, Emily L.The burden of cardiometabolic diseases, including cardiovascular diseases and diabetes, is increasing in sub-Saharan Africa and this has been linked to urbanisation. Helminths, through their immunomodulatory properties, may protect against these disorders. We hypothesised that the rural environment protects against cardiometabolic diseases and that helminths may influence rural-urban disparity of cardiometabolic disease risk.We compared metabolic parameters of individuals aged ≥10 years living in rural, high-helminth-transmission and urban, lower-helminth-transmission settings in Uganda. Cross-sectional surveys were conducted in rural Lake Victoria island fishing communities and in urban sub-wards in Entebbe municipality. Helminth infection and outcomes, including insulin resistance (computed using the homeostatic model assessment of insulin resistance [HOMA-IR]), fasting blood glucose, fasting blood lipids, blood pressure, body mass index (BMI), waist and hip circumference, were assessed.We analysed 1,898 rural and 930 urban participants. Adjusting for BMI, exercise, smoking, alcohol intake, age and sex, urban residents had lower mean fasting glucose (adjusted mean difference [95%CI] 0.18 [-0.32, -0.05] p=0.01) and HOMA-IR (-0.26 [-0.40, -0.11] p=0.001) but higher blood pressure (systolic, 5.45 [3.75, 7.15] p<0.001; diastolic, 1.93 [0.57, 3.29] p=0.006). Current helminth infection did not explain the observed differences.In the Ugandan context, living in rural fishing communities may protect against hypertension but worsen glucose metabolism.Item Correspondence of Neutralizing Humoral Immunity and CD4 T Cell Responses in Long Recovered Sudan Virus Survivors(Viruses, 2016) Sobarzo, Ariel; Herbert, Andrew S.; Ochayon, David E.; Eskira, Yael; Egesa, Moses; Cose, Stephen; Lutwama, Julius Julian; Dye, John M.; Lobel, LeslieRobust humoral and cellular immunity are critical for survival in humans during an ebolavirus infection. However, the interplay between these two arms of immunity is poorly understood. To address this, we examined residual immune responses in survivors of the Sudan virus (SUDV) outbreak in Gulu, Uganda (2000–2001). Cytokine and chemokine expression levels in SUDV stimulated whole blood cultures were assessed by multiplex ELISA and flow cytometry. Antibody and corresponding neutralization titers were also determined. Flow cytometry and multiplex ELISA results demonstrated significantly higher levels of cytokine and chemokine responses in survivors with serological neutralizing activity. This correspondence was not detected in survivors with serum reactivity to SUDV but without neutralization activity. This previously undefined relationship between memory CD4 T cell responses and serological neutralizing capacity in SUDV survivors is key for understanding long lasting immunity in survivors of filovirus infections.Item Effect of isoniazid preventive therapy on immune responses to mycobacterium tuberculosis: an open label randomised, controlled, exploratory study(BMC infectious diseases, 2015) Andia Biraro, Irene; Egesa, Moses; Kimuda, Simon; Smith, Steven G.; Toulza, Frederic; Levin, Jonathan; Joloba, Moses; Katamba, Achilles; Cose, Stephen; Hazel M., Dockrell; Elliott, Alison M.With the renewed emphasis to implement isoniazid preventive therapy (IPT) in Sub-Saharan Africa, we investigated the effect of IPT on immunological profiles among household contacts with latent tuberculosis. Methods: Household contacts of confirmed tuberculosis patients were tested for latent tuberculosis using the QuantiFERON®-TB Gold In-Tube (QFN) assay and tuberculin skin test (TST). HIV negative contacts aged above 5 years, positive to both QFN and TST, were randomly assigned to IPT and monthly visits or monthly visits only. QFN culture supernatants from enrolment and six months’ follow-up were analysed for M.tb-specific Th1, Th2, Th17, and regulatory cytokines by Luminex assay, and for M.tb-specific IgG antibody concentrations by ELISA. Effects of IPT were assessed as the net cytokine and antibody production at the end of six months. Results: Sixteen percent of contacts investigated (47/291) were randomised to IPT (n = 24) or no IPT (n = 23). After adjusting for baseline cytokine or antibody responses, and for presence of a BCG scar, IPT (compared to no IPT) resulted in a relative decline in M.tb-specific production of IFN gamma (adjusted mean difference at the end of six months (bootstrap 95 % confidence interval (CI), p-value) -1488.6 pg/ml ((−2682.5, −294.8), p = 0.01), and IL- 2 (−213.1 pg/ml (−419.2, −7.0), p = 0.04). A similar decline was found in anti-CFP-10 antibody levels (adjusted geometric mean ratio (bootstrap 95 % CI), p-value) 0.58 ((0.35, 0.98), p = 0.04). We found no effect on M.tb-specific Th2 or regulatory or Th17 cytokine responses, or on antibody concentrations to PPD and ESAT-6. Conclusions: IPT led to a decrease in Th1 cytokine production, and also in the anti CFP-10 antibody concentration. This could be secondary to a reduction in mycobacterial burden or as a possible direct effect of isoniazid induced T cell apoptosis, and may have implications for protective immunity following IPT in tuberculosis-endemic countries.Item Factors affecting the infant antibody response to measles immunisation in Entebbe-Uganda(BMC public health,, 2013) Kizito, Dennison; Tweyongyere, Robert; Namatovu, Alice; Webb, Emily L.; Muhangi, Lawrence; Lule, Swaib A.; Bukenya, Henry; Cose, Stephen; Elliott, Alison M.Background: Vaccine failure is an important concern in the tropics with many contributing elements. Among them, it has been suggested that exposure to natural infections might contribute to vaccine failure and recurrent disease outbreaks. We tested this hypothesis by examining the influence of co-infections on maternal and infant measles-specific IgG levels. Methods: We conducted an observational analysis using samples and data that had been collected during a larger randomised controlled trial, the Entebbe Mother and Baby Study (ISRCTN32849447). For the present study, 711 pregnant women and their offspring were considered. Helminth infections including hookworm, Schistosoma mansoni and Mansonella perstans, along with HIV, malaria, and other potential confounding factors were determined in mothers during pregnancy and in their infants at age one year. Infants received their measles immunisation at age nine months. Levels of total IgG against measles were measured in mothers during pregnancy and at delivery, as well as in cord blood and from infants at age one year. Results: Among the 711 pregnant women studied, 66% had at least one helminth infection at enrolment, 41% had hookworm, 20% M. perstans and 19% S. mansoni. Asymptomatic malaria and HIV prevalence was 8% and 10% respectively. At enrolment, 96% of the women had measles-specific IgG levels considered protective (median 4274 mIU/ml (IQR 1784, 7767)). IgG levels in cord blood were positively correlated to maternal measles-specific IgG levels at delivery (r = 0.81, p < 0.0001). Among the infants at one year of age, median measles-specific IgG levels were markedly lower than in maternal and cord blood (median 370 mIU/ml (IQR 198, 656) p < 0.0001). In addition, only 75% of the infants had measles-specific IgG levels considered to be protective. In a multivariate regression analysis, factors associated with reduced measles-specific antibody levels in infancy were maternal malaria infection, infant malaria parasitaemia, infant HIV and infant wasting. There was no association with maternal helminth infection. Conclusion: Malaria and HIV infection in mothers during pregnancy, and in their infants, along with infant malnutrition, may result in reduction of the antibody response to measles immunisation in infancy. This re-emphasises the importance of malaria and HIV control, and support for infant nutrition, as these interventions may have benefits for vaccine efficacy in tropical settings.Item Hyperglycemia in pregnancy diagnosed using glycated hemoglobin (HbA1c) in Uganda: a preliminary cross-sectional report [version 1; peer review: 1 approved](Emerald Open Research, 2020) Bongomin, Felix; Kyazze, Andrew P.; Ninsiima, Sandra; Olum, Ronald; Nattabi, Gloria; Nabakka, Winnie; Kukunda, Rebecca; Batte, Charles; Ssekamatte, Phillip; Baruch Baluku, Joseph; Kibirige, Davis; Cose, Stephen; Andia-Biraro, IreneHyperglycemia in pregnancy (HIP) is a common medical complication during pregnancy and is associated with several short and long-term maternal-fetal consequences. We aimed to determine the prevalence and factors associated with HIP among Ugandan women. Methods: We consecutively enrolled eligible pregnant women attending antenatal care at Kawempe National Referral Hospital, Kampala, Uganda in September 2020. Mothers known to be living with diabetes mellitus or haemoglobinopathies and those with anemia (hemoglobin <11g/dl) were excluded. Random blood sugar (RBS) and glycated hemoglobin A1c (HbA1c) were measured on peripheral venous blood samples. HIP was defined as an HbA1c ≥5.7% with its subsets of diabetes in pregnancy (DIP) and prediabetes defined as HbA1c of ≥6.5% and 5.7-6.4% respectively. ROC curve analysis was performed to determine the optimum cutoff of RBS to screen for HIP. Results: A total of 224 mothers with a mean (± SD) age 26±5 years were enrolled, most of whom were in the 2nd or 3rd trimester (94.6%, n=212) with a mean gestation age of 26.6±7.3 weeks. Prevalence of 6HIP was 11.2% (n=25) (95% CI: 7.7-16.0). Among the mothers with HIP, 2.2% (n=5) had DIP and 8.9% (n=20) prediabetes. Patients with HIP were older (28 years vs. 26 years, p=0.027), had previous tuberculosis (TB) contact (24% vs. 6.5%, p=0.003) and had a bigger hip circumference (107.8 (±10.4) vs. 103.3 (±9.7) cm, p = 0.032). However only previous TB contact was predictive of HIP (odds ratio: 4.4, 95% CI: 1.2-14.0; p=0.022). Using HbA1c as a reference variable, we derived an optimum RBS cutoff of 4.75 mmol/L as predictive of HIP with a sensitivity and specificity of 90.7% and 56.4% (area under the curve = 0.75 (95% CI: 0.70-0.80, p<0.001)), respectively. Conclusions: HIP is common among young Ugandan women, the majority of whom are without identifiable risk factors.Item Impact of Co-Infections and BCG Immunisation on Immune Responses among Household Contacts of Tuberculosis Patients in a Ugandan Cohort(PLoS ONE, 2014) Biraro, Irene A.; Egesa, Moses; Toulza, Frederic; Levin, Jonathan; Cose, Stephen; Joloba, Moses; Smith, Steven; Dockrell, Hazel M.; Katamba, Achilles; Elliott, Alison M.Tuberculosis incidence in resource poor countries remains high. We hypothesized that immune modulating co-infections such as helminths, malaria, and HIV increase susceptibility to latent tuberculosis infection (LTBI), thereby contributing to maintaining the tuberculosis epidemic. Methods: Adults with sputum-positive tuberculosis (index cases) and their eligible household contacts (HHCs) were recruited to a cohort study between May 2011 and January 2012. HHCs were investigated for helminths, malaria, and HIV at enrolment. HHCs were tested using the QuantiFERON-TB Gold In-Tube (QFN) assay at enrolment and six months later. Overnight whole blood culture supernatants from baseline QFN assays were analyzed for cytokine responses using an 11- plex Luminex assay. Associations between outcomes (LTBI or cytokine responses) and exposures (co-infections and other risk factors) were examined using multivariable logistic and linear regression models. Results: We enrolled 101 index cases and 291 HHCs. Among HHCs, baseline prevalence of helminths was 9% (25/291), malaria 16% (47/291), HIV 6% (16/291), and LTBI 65% (179/277). Adjusting for other risk factors and household clustering, there was no association between LTBI and any co-infection at baseline or at six months: adjusted odds ratio (95% confidence interval (CI); p-value) at baseline for any helminth, 1.01 (0.39–2.66; 0.96); hookworm, 2.81 (0.56–14.14; 0.20); malaria, 1.06 (0.48–2.35; 0.87); HIV, 0.74 (0.22–2.47; 0.63). HHCs with LTBI had elevated cytokine responses to tuberculosis antigens but co-infections had little effect on cytokine responses. Exploring other risk factors, Th1 cytokines among LTBIpositive HHCs with BCG scars were greatly reduced compared to those without scars: (adjusted geometric mean ratio) IFNc 0.20 (0.09–0.42), ,0.0001; IL-2 0.34 (0.20–0.59), ,0.0001; and TNFa 0.36 (0.16–0.79), 0.01. Conclusions: We found no evidence that co-infections increase the risk of LTBI, or influence the cytokine response profile among those with LTBI. Prior BCG exposure may reduce Th1 cytokine responses in LTBI.Item The impact of maternal infection with Mycobacterium tuberculosis on the infant response to bacille Calmette–Gue´rin immunization(Philosophical Transactions of the Royal Society B: Biological Sciences, 2015) Mawa, Patrice A.; Nkurunungi, Gyaviira; Egesa, Moses; Webb, Emily L.; Smith, Steven G.; Kizindo, Robert; Akello, Mirriam; Lule, Swaib A.; Muwanga, Moses; Dockrell, Hazel M.; Cose, Stephen; Elliott, Alison M.Bacille Calmette–Gue´rin (BCG) immunization provides variable protection against tuberculosis. Prenatal antigen exposure may have lifelong effects on responses to related antigens and pathogens. We therefore hypothesized that maternal latent Mycobacterium tuberculosis infection (LTBI) influences infant responses to BCG immunization at birth. We measured antibody (n ¼ 53) and cellular (n ¼ 31) responses to M. tuberculosis purified protein derivative (PPD) in infants of mothers with and without LTBI, in cord blood and at one and six weeks after BCG. The concentrations of PPD-specific antibodies declined between birth (median [interquartile range (IQR)]) 5600 ng ml21 [3300–11 050] in cord blood) and sixweeks (0.00 ng ml21 [0–288]). Frequencies of PPD-specific IFN-g-expressing CD4þT cells increased at one week and declined between one and six weeks ( p ¼ 0.031). Frequencies of IL-2- and TNF-a-expressing PPD-specific CD4þT cells increased between one and six weeks ( p ¼ 0.019, p ¼ 0.009, respectively). At one week, the frequency of PPD-specific CD4þT cells expressing any of the three cytokines, combined, was lower among infants of mothers with LTBI, in crude analyses ( p ¼ 0.002) and after adjusting for confounders (mean difference, 95% CI 20.041% (20.082, 20.001)). In conclusion, maternal LTBI was associated with lower infant anti-mycobacterial T-cell responses immediately following BCGimmunization. These findings are being explored further in a larger study.Item Latent Tuberculosis Infection Status of Pregnant Women in Uganda Determined Using QuantiFERON TB Gold-Plus(Oxford University Press, 2021) Bongomin, Felix; Ssekamatte, Phillip; Nattabi, Gloria; Olum, Ronald; Ninsiima, Sandra; Kyazze, Andrew Peter; Nabakka, Winnie; Kukunda, Rebecca; Cose, Stephen; Kibirige, Davis; Batte, Charles; Kaddumukasa, Mark; Kirenga, Bruce J.; Nakimuli, Annettee; Baruch Baluku, Joseph; ndia-Biraro, Irene AThe risk of progression of latent tuberculosis infection (LTBI) to active disease increases with pregnancy. This study determined the prevalence and risk factors associated with LTBI among pregnant women in Uganda. Methods. We enrolled 261 pregnant women, irrespective of gestational age. Participants who had known or suspected active tuberculosis (TB) on the basis of clinical evaluation or who had recently received treatment for TB were excluded. LTBI was defined as an interferon-γ concentration ≥0.35 IU/mL (calculated as either TB1 [eliciting CD4+ T-cell responses] or TB2 [eliciting CD8+ T-cell responses] antigen minus nil) using QuantiFERON TB Gold-Plus (QFT-plus) assay. Results. LTBI prevalence was 37.9% (n = 99) (95% confidence interval [CI], 32.3–44.0). However, 24 (9.2%) subjects had indeterminate QFT-plus results. Among participants with LTBI, TB1 and TB2 alone were positive in 11 (11.1%) and 18 (18.2%) participants, respectively. In multivariable analysis, human immunodeficiency virus (HIV) infection (adjusted odds ratio [aOR], 4.4 [95% confidence interval {CI}, 1.1–18.0]; P = .04) and age 30–39 years (aOR, 4.0 [95% CI, 1.2–12.7]; P = .02) were independently associated with LTBI. Meanwhile, smoking status, alcohol use, nature of residence, crowding index, and TB contact were not associated with LTBI. Conclusions. Our findings are in keeping with the evidence that HIV infection and advancing age are important risk factors for LTBI in pregnancy. In our setting, we recommend routine screening for LTBI and TB preventive therapy among eligible pregnant women.Item Marburg Virus Survivor Immune Responses are Th1 Skewed with Limited Neutralizing Antibody Responses(Journal of Experimental Medicine, 2017) Stonier, Spencer W.; Herbert, Andrew S.; James, Rebekah M.; Egesa, Moses; Cose, Stephen; Lutwama, Julius Julian; Dye, John M.Until recently, immune responses in filovirus survivors remained poorly understood. Early studies revealed IgM and IgG responses to infection with various filoviruses, but recent outbreaks have greatly expanded our understanding of filovirus immune responses. Immune responses in survivors of Ebola virus (EBOV) and Sudan virus (SUDV) infections have provided the most insight, with T cell responses as well as detailed antibody responses having been characterized. Immune responses to Marburg virus (MARV), however, remain almost entirely uncharacterized. We report that immune responses in MARV survivors share characteristics with EBOV and SUDV infections but have some distinct differences. MARV survivors developed multivariate CD4+ T cell responses but limited CD8+ T cell responses, more in keeping with SUDV survivors than EBOV survivors. In stark contrast to SUDV survivors, rare neutralizing antibody responses in MARV survivors diminished rapidly after the outbreak. These results warrant serious consideration for any vaccine or therapeutic that seeks to be broadly protective, as different filoviruses may require different immune responses to achieve immunityItem Mycobacterium Tuberculosis Infection Boosts B Cell 2 Responses to Unrelated Pathogens(bioRxiv, 2019) Kimuda, Simon G.; Andia-Biraro, Irene; Sebina, Ismail; Egesa, Moses; Nalwoga, Angela; Bagaya, Bernard S.; Elliott, Alison M.; Cose, StephenAntigens from Mycobacterium tuberculosis (M.tb), have been shown to stimulate human B cell responses to unrelated recall antigens in vitro. However, it is not known whether natural M.tb infection or whether vaccination with the related species, Mycobacterium bovis BCG, has a similar effect. This study investigated the effects of M.tb infection and BCG vaccination on B cell responses to heterologous pathogen recall antigens. Antibodies against several bacterial and viral pathogens were quantified by ELISA in 68 uninfected controls, 62 individuals with latent TB infection (LTBI) and 107 active pulmonary TB (APTB) cases, and 24 recently BCG-vaccinated adolescents and naive controls. Antibody avidity was investigated using surface plasmon resonance and B cell ELISPOT assays were used to measure plasmablast and memory B cell responses (MBC) in APTB cases and healthy donor controls. APTB was associated with higher levels of antibodies to tetanus toxoid (TT), diphtheria toxoid, respiratory syncytial virus, measles virus and Kaposi’s sarcoma herpesvirus, compared to uninfected controls. Vaccination with BCG did not alter levels of antibodies against heterologous pathogens. TT-specific antibody avidity was increased in APTB and the ratio of TT-specific plasmablasts to MBCs in the APTB cases was 7:1. M.tb infection boosts serological memory to heterologous pathogens in human subjects and this process may be driven by polyclonal activation of memory B cells.Item Mycobacterium Tuberculosis Infection is Associated with Increased B Cell Responses to Unrelated Pathogens(Scientific reports, 2020) Kimuda, Simon G.; Andia‑Biraro, Irene; Sebina, Ismail; Egesa, Moses; Nalwoga, Angela; Smith, Steven G.; Bagaya, Bernard S.; Levin, Jonathan; Elliott, Alison M.; Cose, StephenAntigens from Mycobacterium tuberculosis (M.tb), have been shown to stimulate human B cell responses to unrelated recall antigens in vitro. However, it is not known whether natural M.tb infection or whether vaccination with, Mycobacterium bovis BCG, has a similar efect. This study investigated the efects of M.tb infection and BCG vaccination on B cell responses to heterologous pathogen recall antigens. Antibodies against several bacterial and viral pathogens were quantifed by ELISA in 68 uninfected controls, 62 individuals with latent TB infection (LTBI) and 107 active pulmonary TB (APTB) cases, and 24 recently BCG-vaccinated adolescents and naive controls. Antibody avidity was investigated using surface plasmon resonance and B cell ELISPOTs were used to measure plasmablast and memory B cell responses (MBC) in APTB cases and healthy donor controls. APTB was associated with higher levels of antibodies to respiratory syncytial virus and measles virus, compared to uninfected controls. BCG vaccination did not alter levels of antibodies against heterologous pathogens. Tetanus toxoid (TT)-specifc antibody avidity was increased in APTB cases in comparison to uninfected individuals and the ratio of TT-specifc plasmablasts to MBCs in the APTB cases was 7:1. M.tb infection is associated with increased antibody responses to heterologous pathogens in human subjects.Item Rethinking Schistosomiasis Vaccine Development(Trends in parasitology, 2017) Egesa, Moses; Hoffmann, Karl F.; Yazdanbakhsh, Maria; Cose, StephenThere is currently no vaccine against schistosomiasis. With few Schistosoma vaccine candidates in clinical trials, unexplored antigens from the vulnerable schistosomulum should be considered as possible vaccine candidates. In addition, we suggest developing synthetic vesicles as a new delivery vehicle and adjuvant for immunoprophylactic schistosomula vaccine candidates.Item Risk Assessment for the Implementation of Controlled Human Schistosoma Mansoni Infection Trials in Uganda(AAS open research, 2019) Koopman, Jan Pieter; Egesa, Moses; Wajja, Anne; Adriko, Moses; Nassuuna, Jacent; Nkurunungi, Gyaviira; Driciru, Emmanuella; Cose, Stephen; Kaleebu, Pontiano; Kabatereine, Narcis; Tukahebwa, Edridah; Elliott, Alison M.Schistosomiasis is a parasitic infection highly prevalent in sub-Saharan Africa, and a significant cause of morbidity; it is a priority for vaccine development. A controlled human infection model for Schistosoma mansoni (CHI-S) with potential to accelerate vaccine development has been developed among naïve volunteers in the Netherlands. Because responses both to infections and candidate vaccines are likely to differ between endemic and non-endemic settings, we propose to establish a CHI-S in Uganda where Schistosoma mansoni is endemic. As part of a “road-map” to this goal, we have undertaken a risk assessment. We identified risks related to importing of laboratory vector snails and schistosome strains from the Netherlands to Uganda; exposure to natural infection in endemic settings concurrently with CHI-S studies, and unfamiliarity of the community with the nature, risks and rationale for CHI. Mitigating strategies are proposed. With careful implementation of the latter, we believe that CHI-S can be implemented safely in Uganda. Our reflections are presented here to promote feedback and discussion.Item Safety and immunogenicity of ChAdOx1 85A prime followed by MVA85A boost compared with BCG revaccination among Ugandan adolescents who received BCG at birth: a randomised, open-label trial(Elsevier Ltd, 2024-03) Wajja, Anne; Nassanga, Beatrice; Natukunda, Agnes; Serubanja, Joel; Tumusiime, Josephine; Akurut, Helen; Oduru, Gloria; Nassuuna, Jacent; Kabagenyi, Joyce; Morrison, Hazel; Scott, Hannah; Doherty, Rebecca Powell; Marshall, Julia L; Puig, Ingrid Cabrera; Cose, Stephen; Kaleebu, Pontiano; Webb, Emily L; Satti, Iman; McShane, Helen; Elliott, Alison M; Namutebi, Milly; Nakazibwe, Esther; Onen, Caroline; Apuule, Barbara; Akello, Florence; Mukasa, Mike; Nnaluwooza, Marble; Sewankambo, Moses; Kiwanuka, Sam; Kiwudhu, Fred; Imede, Esther; Nkurunungi, Gyaviira; Nakawungu, Prossy Kabuubi; Kabami, Grace; Nuwagaba, Emmanuel; Akello, MirriamAbstract BACKGROUNDBCG confers reduced, variable protection against pulmonary tuberculosis. A more effective vaccine is needed. We evaluated the safety and immunogenicity of candidate regimen ChAdOx1 85A-MVA85A compared with BCG revaccination among Ugandan adolescents.METHODSAfter ChAdOx1 85A dose escalation and age de-escalation, we did a randomised open-label phase 2a trial among healthy adolescents aged 12-17 years, who were BCG vaccinated at birth, without evident tuberculosis exposure, in Entebbe, Uganda. Participants were randomly assigned (1:1) using a block size of 6, to ChAdOx1 85A followed by MVA85A (on day 56) or BCG (Moscow strain). Laboratory staff were masked to group assignment. Primary outcomes were solicited and unsolicited adverse events (AEs) up to day 28 and serious adverse events (SAEs) throughout the trial; and IFN-γ ELISpot response to antigen 85A (day 63 [geometric mean] and days 0-224 [area under the curve; AUC).FINDINGSSix adults (group 1, n=3; group 2, n=3) and six adolescents (group 3, n=3; group 4, n=3) were enrolled in the ChAdOx1 85A-only dose-escalation and age de-escalation studies (July to August, 2019). In the phase 2a trial, 60 adolescents were randomly assigned to ChAdOx1 85A-MVA85A (group 5, n=30) or BCG (group 6, n=30; December, 2019, to October, 2020). All 60 participants from groups 5 and 6 were included in the safety analysis, with 28 of 30 from group 5 (ChAdOx1 85A-MVA85A) and 29 of 30 from group 6 (BCG revaccination) analysed for immunogenicity outcomes. In the randomised trial, 60 AEs were reported among 23 (77%) of 30 participants following ChAdOx1 85A-MVA85A, 31 were systemic, with one severe event that occurred after the MVA85A boost that was rapidly self-limiting. All 30 participants in the BCG revaccination group reported at least one mild to moderate solicited AE; most were local reactions. There were no SAEs in either group. Ag85A-specific IFN-γ ELISpot responses peaked on day 63 in the ChAdOx1 85A-MVA85A group and were higher in the ChAdOx1 85A-MVA85A group compared with the BCG revaccination group (geometric mean ratio 30·59 [95% CI 17·46-53·59], p<0·0001, day 63; AUC mean difference 57 091 [95% CI 40 524-73 658], p<0·0001, days 0-224).INTERPRETATIONThe ChAdOx1 85A-MVA85A regimen was safe and induced stronger Ag85A-specific responses than BCG revaccination. Our findings support further development of booster tuberculosis vaccines.FUNDINGUK Research and Innovations and Medical Research Council.TRANSLATIONSFor the Swahili and Luganda translations of the abstract see Supplementary Materials section.Item Schistosoma Mansoni schistosomula Antigens Induce Th1/ Pro-inflammatory Cytokine Responses(Parasite immunology, 2018) Egesa, Moses; Lubyayi, Lawrence; Tukahebwa, Edridah M.; Bagaya, Bernard S.; Wilson, Shona; Yazdanbakhsh, Maria; Labuda, Lucja A.; Cose, StephenLarvae of Schistosoma (schistosomula) are highly susceptible to host immune responses and are attractive prophylactic vaccine targets, although cellular immune responses against schistosomula antigens in endemic human populations are not well characterized. We collected blood and stool from 54 Schistosoma mansoni-infected Ugandans, isolated peripheral blood mononuclear cells and stimulated them for 24 hours with schistosome adult worm and soluble egg antigens (AWA and SEA), along with schistosomula recombinant proteins rSmKK7, Lymphocyte Antigen 6 isoforms (rSmLy6A and rSmLy6B), tetraspanin isoforms (rSmTSP6 and rSmTSP7). Cytokines, chemokines and growth factors were measured in the culture supernatants using a multiplex luminex assay, and infection intensity was determined before and at 1 year after praziquantel (PZQ) treatment using the Kato-Katz method. Cellular responses were grouped and the relationship between groups of correlated cellular responses and infection intensity before and after PZQ treatment was investigated. AWA and SEA induced mainly Th2 responses. In contrast, rSmLy6B, rSmTSP6 and rSmTSP7 induced Th1/pro-inflammatory responses. While recombinant antigens rSmKK7 and rSmLy6A did not induce a Th1/pro-inflammatory response, they had an association with pre-treatment infection intensity after adjusting for age and sex. Testing more schistosomula antigens using this approach could provide immune-epidemiology identifiers necessary for prioritizing next generation schistosomiasis vaccine candidates.