Browsing by Author "Kaul, Rupert"

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    The Effect of Antiretroviral Therapy Initiation on the Vaginal Microbiome in HIV-Infected Women
    (The Journal of infectious diseases, 2021) Liu, Cindy M.; Packman, Zoe R.; Abraham, Alison G.; Serwadda, David M.; Nalugoda, Fred; Aziz, Maliha; Prodger, Jessica L.; Kaul, Rupert; Kalibbala, Sarah; Gray, Ronald H.; Price, Lance B.; Quinn, Thomas C.; Tobian, Aaron A.R.; Reynolds, Steven J.
    The impact of antiretroviral therapy (ART) initiation on the vaginal microbiome is unknown. This is of particular importance among women living in sub-Saharan Africa. Understanding this relationship could help elucidate if and how the host immune system interacts with the vaginal microbiome. Methods. The vaginal microbiome of HIV-1/HSV-2-coinfected women (n = 92) in Uganda was evaluated from self-collected vaginal swabs 1 month pre-ART and at 4 and 6 months post–ART initiation. The vaginal microbiome was characterized by 16S rRNA genebased sequencing and quantitative polymerase chain reaction. Vaginal community state types (CSTs) were identified using proportional abundance data. Changes in microbiome composition were assessed with permutational analyses of variance (PerMANOVA).
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    HIV Infection in Uncircumcised Men is Associated with Altered CD8 T-cell Function but Normal CD4 T-cell Numbers in the Foreskin
    (The Journal of infectious diseases, 2014) Prodger, Jessica L.; Hirbod, Taha; Gray, Ronald; Kigozi, Godfrey; Nalugoda, Fred; Galiwango, Ronald; Reynolds, Steven J.; Huibner, Sanja; Wawer, Maria J.; Serwadda, David; Kaul, Rupert; Rakai, Genital Immunology Research Group
    Human immunodeficiency virus (HIV)–infected (HIV+) men are more susceptible to sexually transmitted infections, and may be superinfected by HIV. We hypothesized that HIV induces immune alterations in the foreskin that may impact the subsequent acquisition/clearance of genital coinfections. Methods. Foreskin tissue and blood were obtained from 70 HIV-uninfected and 20 HIV+ men undergoing circumcision. T cells were characterized by flow cytometry, immunohistochemistry, and polymerase chain reaction. Results. There was substantial influx of CD8 T-cells into the foreskins of HIV+ men (108.8 vs 23.1 cells/mm2; P < .001); but foreskin CD4 T-cell density was unchanged (43.0 vs 33.7/mm2; P = .67), despite substantial blood depletion (409.0 vs 877.8 cells/μL; P < .001). While frequencies of foreskin C-C chemokine receptor type 5+ (CCR5+) T cells, T regulatory cells, and T-helper 17 cells were unaltered in HIV+ men, CD8 T-cell production of tumor necrosis factor α (TNFα) was decreased. HIV-specific CD8 T cells were present in the foreskins of HIV+ men, although their frequency and function was reduced compared to the blood. Conclusions. Foreskin CD4 T-cell density and CCR5 expression were not reduced during HIV infection, perhaps explaining susceptibility to HIV superinfection. Foreskin CD8 T-cell density was increased, but decreased production of TNFα may enhance susceptibility to genital coinfections in HIV+ men.
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    Immune milieu and microbiome of the distal urethra in Ugandan men: impact of penile circumcision and implications for HIV susceptibility
    (Microbiome, 2022) Galiwango, Ronald M.; Park, Daniel E.; Huibner, Sanja; Onos, Abigail; Aziz, Maliha; Roach, Kelsey; Anok, Aggrey; Nnamutete, James; Isabirye, Yahaya; Wasswa, John Bosco; Male, Deo; Kigozi, Godfrey; Tobian, Aaron A. R.; Prodger, Jessica L.; Liu, Cindy M.; Kaul, Rupert
    Coronal sulcus (CS) anaerobe abundance and IL-8 levels are linked to HIV acquisition, and are dramatically reduced after penile circumcision (PC). The distal urethra may be the site of some HIV acquisition before PC, and presumably most acquisition post PC. We describe the immune milieu and microbiome of the distal urethra in uncircumcised Ugandan men, and define the impact of PC. Participants consisted of HIV-negative, genital symptomfree adult Ugandan men undergoing PC (n = 51). Urethral and coronal sulcus swabs were collected at baseline and at 6- and 12-months post-PC. Soluble immune factors were quantified by multiplex ELISA, and bacterial abundance assessed by 16S rRNA qPCR and sequencing. Results: At baseline, the urethra was enriched compared to the CS for most cytokines (including IL-8 and MIP-1β) and soluble E-cadherin (sE-cadherin, an epithelial disruption marker), although CS levels of IL-1α and IL-1β were higher. Baseline total bacterial abundance was ≥ 20-fold higher in the CS than the urethra (median 27,100 vs. 1200 gene copies/swab, p = 0.001), and anaerobes comprised 58% of CS bacteria vs. 42% of urethral bacteria. PC did not alter urethral IL-8 (median 806 at baseline vs. 1130 pg/ml at 12 months; p = 0.062) and urethral sE-cadherin increased (113,223 vs. 158,385 pg/ml, p = 0.009), despite five- and sevenfold drops in total bacterial and anaerobe abundance after PC, respectively. However, PC dramatically reduced CS levels of sE-cadherin (15,843 vs. 837 pg/ml, p < 0.001) and most cytokines (IL-8; 34 vs. 3 pg/ml, p < 0.001), while reducing total bacterial and anaerobe abundance by 13-fold and 60-fold, respectively (both P ≤ 0.004). Conclusions: The urethra is immunologically rich with characteristics of an HIV-susceptible tissue site. However, PC had no impact on urethral immunology and may have reduced epithelial integrity, despite modest reductions in total bacteria and anaerobes, suggesting that HIV protection from PC is not mediated via immune or microbiome alterations in the urethra.
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    Immunological Signaling During Herpes Simplex Virus-2 and Cytomegalovirus Vaginal Shedding After Initiation of Antiretroviral Treatment
    (Oxford University Press, 2016) Nason, Martha C.; Patel, Eshan U.; Kirkpatrick, Allison R.; Prodger, Jessica L.; Shahabi, Kamnoosh; Tobian, Aaron A. R.; Gianella, Sara; Kalibbala, Sarah; Ssebbowa, Paschal; Kaul, Rupert; Gray, Ronald H.; Quinn, Thomas C.; Serwadda, David; Reynolds, Steven J.; Redd, Andrew D.
    Vaginal proinflammatory cytokine expression during herpes virus reactivation was examined in human immunodeficiency virus infected women before and after initiation of antiretroviral therapy (ART). Vaginal swabs were screened for levels of cytokines interleukin (IL)-1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p70, IL-13, tumor necrosis factor (TNF)-α, and interferon- γ. The relative risk (RR) of herpes simplex virus-2 or cytomegalovirus (CMV) shedding being associated with cytokine levels above the median were estimated. Herpes simplex virus-2 shedding was significantly associated with higher levels of IL-6 (RR = 1.4, P = .003) and TNF-α (RR = 1.3, P = .010), whereas CMV shedding was associated with higher IL-6 (RR = 1.3, P = .006) and IL-2 (RR = 1.4, P = .01). The association of viral shedding with higher IL-6 levels suggests that herpes virus reactivation may be playing a role in immune activation after ART initiation.
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    No Difference in Keratin Thickness between Inner and Outer Foreskins from Elective Male Circumcisions in Rakai, Uganda
    (PLoS ONE, 2012) Dinh, Minh H.; Hirbod, Taha; Kigozi, Godfrey; Okocha, Eneniziaogochukwu A.; Cianci, Gianguido C.; Kong, Xiangrong; Prodger, Jessica L.; Broliden, Kristina; Kaul, Rupert; Serwadda, David; Wawer, Maria J.; Gray, Ronald H.; Hope, Thomas J.
    It has been hypothesized that increased HIV acquisition in uncircumcised men may relate to a more thinly keratinized inner foreskin. However, published data are contradictory and potentially confounded by medical indications for circumcision. We tested the hypothesis that the inner foreskin was more thinly keratinized than the outer foreskin using tissues from 19 healthy, HIV-uninfected men undergoing routine prophylactic circumcision in Rakai, Uganda. Sections from 3 foreskin anatomic sites (inner, outer, and frenar band) were snap-frozen separately. Two independent laboratories each separately stained, imaged, and measured keratin thicknesses in a blinded fashion. There was no significant difference in keratin thickness between the inner (mean = 14.6767.48 mm) and outer (mean = 13.3068.49 mm) foreskin, or between the inner foreskin and the frenar band (mean = 16.91612.42 mm). While the frenar band showed the greatest intra-individual heterogeneity in keratin thickness, there was substantial inter-individual variation seen in all regions. Measurements made by the two laboratories showed high correlation (r = 0.741, 95% CI, 0.533–0.864). We conclude that, despite inter- and intra-individual variability, keratin thickness was similar in the inner and outer foreskin of healthy Ugandan men, and that reduced keratin thickness is not likely to make the inner foreskin more susceptible to HIV acquisition.