Chia C. Wang

The Effect of Treatment of Vaginal Infections on Shedding of Human Immunodeficiency Virus Type 1

To assess the effect of treatment of vaginal infections on vaginal shedding of cell-free human immunodeficiency virus type 1 (HIV-1) and HIV-1-infected cells, HIV-1-seropositive women were examined before and after treatment of Candida vulvovaginitis, Trichomonas vaginitis, and bacterial vaginosis. For Candida (n=98), vaginal HIV-1 RNA decreased from 3.36 to 2.86 log(10) copies/swab (P<.001), as did the prevalence of HIV-1 DNA (36% to 17%; odds ratio [OR], 2.8; 95% confidence interval [CI], 1.3-6.5). For Trichomonas vaginitis (n=55), HIV-1 RNA decreased from 3.67 to 3.05 log(10) copies/swab (P<.001), but the prevalence of HIV-1 DNA remained unchanged (22%-25%; OR, 0.8; 95% CI, 0.3-2.2). For bacterial vaginosis (n=73), neither the shedding of HIV-1 RNA (from 3.11 to 2.90 log(10) copies/swab; P=.14) nor the prevalence of DNA (from 21% to 23%; OR, 0.8; 95% CI, 0.3-2.0) changed. Vaginal HIV-1 decreased 3.2- and 4.2-fold after treating Candida and Trichomonas, respectively. These data suggest that HIV-1 transmission intervention strategies that incorporate diagnosis and treatment of these prevalent infections warrant evaluation.

Decreased NK cell frequency in chronic hepatitis C does not affect ex vivo cytolytic killing

Prior studies have suggested that natural killer (NK) cell function might be impaired in chronic hepatitis C virus (HCV) infection. Circulating NK cell frequency and cytolytic activity were examined freshly ex vivo in HCV‐infected and uninfected subjects. Surprisingly, the intrinsic cytolytic activity of peripheral blood NK‐enriched cells was similar between HCV‐infected and uninfected groups (P = .91). Although the percentage of circulating CD3−CD16/56+NK cells was 30% lower in HCV‐infected compared with uninfected subjects (P = .02) paralleled by a decrease of CD56dim cytolytic NK cells (P = .02), overall K562 cytolysis by unfractionated peripheral blood mononuclear cells was not affected (P = .29). Analysis of the relationships between NK cytolytic activity and other clinical information revealed an inverse association with liver fibrosis stage (P = .035). In conclusion, NK cell cytolytic function does not appear to be impaired in chronic hepatitis C, but higher levels of NK cell cytolysis are associated with less liver fibrosis. (HEPATOLOGY 2006;43:573–580.)

Treatment of cervicitis is associated with decreased cervical shedding of HIV-1.

ObjectiveTo determine whether cervical mucosal shedding of HIV-1 RNA and HIV-1 infected cells decreases following successful treatment of cervicitis. DesignProspective interventional study. SettingSexually Transmitted Infections Clinic, Coast Provincial General Hospital, Mombasa, Kenya. ParticipantsThirty-six HIV-1 seropositive women with cervicitis: 16 with Neisseria gonorrhoeae, seven with Chlamydia trachomatis, and 13 with non-specific cervicitis. InterventionsTreatment of cervicitis. Main outcome measuresLevels of total (cell-free and cell-associated) HIV-1 RNA and presence of HIV-1 DNA (a marker for infected cells) in cervical secretions before and after resolution of cervicitis. ResultsAfter treatment of cervicitis, the median HIV-1 RNA concentration in cervical secretions was reduced from 4.05 to 3.24 log10 copies/swab (P = 0.001). Significant decreases in cervical HIV-1 RNA occurred in the subgroups with N. gonorrhoeae (3.94 to 3.28 log10 copies/swab;P = 0.02) and C. trachomatis (4.21 to 3.19 log10 copies/swab;P = 0.02). Overall, the prevalence of HIV-1 infected cells in cervical secretions also decreased after treatment, from 67% to 42% (odds ratio, 2.8; 95% confidence interval, 1.3–6.0;P = 0.009). Detection of infected cells was associated with higher mean HIV-1 RNA levels (4.04 versus 2.99 log10copies/swab;P < 0.0001). ConclusionsEffective treatment of cervicitis resulted in significant decreases in shedding of HIV-1 virus and infected cells in cervical secretions. Treatment of sexually transmitted diseases may be an important means of decreasing the infectivity of HIV-1 seropositive women by reducing exposure to HIV-1 in genital secretions.

Acute Hepatitis C in a Contemporary US Cohort: Modes of Acquisition and Factors Influencing Viral Clearance

BACKGROUND Acute hepatitis C virus (HCV) infection is often asymptomatic; thus, its epidemiology and natural history are difficult to define. METHODS Acute HCV infection was identified on the basis of HCV seroconversion within 1 year (n=45), new anti-HCV seropositivity with clinical acute hepatitis (n=21), or HCV strain sequencing after an iatrogenic exposure (n=1). Risk factors were assessed with a baseline questionnaire, and participants were followed up prospectively with serial measurement of viral loads. RESULTS Of 67 persons with acute HCV infection, most were asymptomatic (64%) and injection drug users (66%). Thirteen had an unknown mode of transmission; of these, 11 reported high-risk sexual behavior. Ten acquired acute HCV infection within 3 months of an iatrogenic exposure; 3 had confirmed iatrogenic infection, and 4 had no other risk factors identified. The spontaneous viral clearance rate after 6 months of infection was 18% (95% confidence interval, 11%-31%). The rate of viral clearance varied significantly by sex (34% vs. 3% for women vs. men; P<.001). CONCLUSIONS High-risk sexual or iatrogenic exposures may be important contemporary risk factors for HCV infection. The spontaneous viral clearance rate (18%) in this contemporary study was similar to that reported for past studies of transfusion-associated HCV infection. Women were more likely to clear acute HCV infection than men.

Association between cervical shedding of herpes simplex virus and HIV-1.

Objective: To investigate the association between the cervical shedding of herpes simplex virus (HSV) and HIV-1. Design: A cross-sectional study on 200 women seropositive for both HSV-2 and HIV-1 was conducted in a family planning clinic at the Coast Provincial General Hospital, Mombasa, Kenya. Main outcome measures: Quantities of HSV DNA (types 1 and 2) and HIV-1 RNA as well as the presence or absence of HIV-1 proviral DNA in cervical secretions were determined and compared. Results: There was a significant correlation between the quantities of HSV DNA and HIV-1 RNA in the cervical secretions of HSV-shedding women (Pearsons r = 0.24, P = 0.05). A 10-fold increase in the quantity of cervical HSV DNA was associated with 1.35-fold higher cervical HIV-1-RNA levels (95% CI 1.00–1.81; P = 0.05), and with 1.36-fold greater odds of detection of HIV-1 proviral DNA (95% CI 1.05–1.75; P = 0.02). Conclusion: Higher levels of cervical HSV were associated with higher levels of expressed HIV-1 and with the more frequent detection of HIV-1-infected cells in cervical secretions. Prospective studies are needed to explore further the association between non-ulcerative cervical HSV reactivation and HIV-1 shedding. Such a relationship may have important implications for interventions designed to slow the spread of HIV-1.

The effect of hormonal contraception on genital tract shedding of HIV-1.

Objective: A previous cross-sectional study reported that hormonal contraception may be associated with increased infectivity in HIV-1 infected women. We conducted a prospective study to determine if cervical shedding of HIV-1 increased after initiating hormonal contraception. Design: Shedding of HIV-1 DNA (a marker of HIV-1 infected cells) and HIV-1 RNA were measured before and after initiating hormonal contraception. Methods: HIV-1 seropositive women were recruited from a Kenyan family planning clinic. At baseline, cervical secretions were collected for HIV-1 DNA and RNA assays in women initiating hormonal contraception; follow-up samples were collected a median of 64 days later. Results: One-hundred and one women chose depot medroxyprogesterone (Depo), 53 chose low-dose oral contraceptives (OC), seven high-dose OC, and 52 progesterone-only OC. At follow-up, there was a significant increase in the prevalence of cervical HIV-1 DNA detection [from 42% to 52%, odds ratio (OR), 1.62; 95% confidence interval (CI), 1.03–2.63) for all hormonal contraception combined, and a trend for an increase for each individual type. Although the prevalence of cervical HIV-1 RNA increased slightly (from 82% to 86%; OR, 1.56; 95% CI, 0.83–3.03), the concentration of cervical HIV-1 RNA did not change significantly overall (from 2.81 to 2.84 log10 copies/swab; P = 0.77) or for individual contraception types. Conclusions: A modest but significant increase in shedding of HIV-1 DNA but not of HIV-1 RNA was detected after starting hormonal contraception. Our results may have important implications regarding the infectivity of women using hormonal contraception, and highlight the need for epidemiologic studies of transmission rates from women using and not using hormonal contraception.

Functional Suppression by FoxP3+CD4+CD25high Regulatory T Cells during Acute Hepatitis C Virus Infection

BACKGROUND Infection with hepatitis C virus (HCV) is characterized by impairment of viral effector T cell responses and a high propensity for viral persistence. Previous studies have demonstrated that chronic HCV infection is associated with an increased frequency of regulatory T (T(reg)) cells, compared with that in persons whose infection resolved and in healthy persons. However, all patients in prior analyses had exposures in the distant past, precluding the ability to determine whether T(reg) cells play a causal role in establishing persistence during the earliest stages of infection or whether they are expanded because of viral persistence. METHODS For the first time, we longitudinally analyzed T(reg) cells in patients with acute HCV infection (n = 27). We used a multiparameter approach, including fluorescence-activated cell sorting analysis of cell-surface and intracellular antigens, coculture experiments with highly purified CD4(+)CD25(high) regulatory and CD4(+)CD25(-) responder cell populations, and multiplex analysis of secreted cytokines. RESULTS Forkhead transcription factor 3 (FoxP3) expression and T(reg) cell suppression were greater in patients with acute HCV infection than in healthy control subjects but were not different at the first time point among patients who subsequently developed persistence or resolved HCV infection spontaneously; however, 6 months later, the resolution of disease was associated with a relative loss of functional suppression. CONCLUSIONS Collectively, these data indicate that patients with acute HCV infection who develop chronicity versus spontaneous resolution exhibit temporal changes in T(reg) cell function. It is possible that repetitive viral antigenic stimulation alters the function of T(reg) cells over time.

Silymarin Inhibits In Vitro T-Cell Proliferation and Cytokine Production in Hepatitis C Virus Infection

BACKGROUND & AIMS Silymarin, an extract from the seeds of the milk thistle plant Silybum marianum, has been used for centuries for the treatment of chronic liver diseases. Despite common use by patients with hepatitis C in the United States, its clinical efficacy remains uncertain. The goal of this study was to determine whether silymarin has in vitro effects on immune function that might have implications for its potential effect on hepatitis C virus (HCV)-induced liver disease. METHODS Freshly isolated peripheral blood mononuclear cells (PBMC) and T cells from HCV-infected and uninfected subjects were tested in vitro for responses to nonspecific and antigenic stimulation in the presence and absence of a standardized preparation of silymarin (MK001). RESULTS Minimal MK001 toxicity on PBMC was found at concentrations between 5 and 40 microg/mL. MK001 dose dependently inhibited the proliferation and secretion of tumor necrosis factor (TNF)-alpha, interferon (IFN)-gamma, and interleukin (IL)-2 by PBMC stimulated with anti-CD3. In addition, MK001 inhibited proliferation by CD4(+) T cells to HCV, Candida, and tetanus protein antigens and by HLA-A2/HCV 1406-1415-specific CD8(+) T cells to allogeneic stimulation. MK001 inhibited T-cell TNF-alpha and IFN-gamma cytokine secretion to tetanus and Candida protein antigens. Finally, MK001 inhibited nuclear factor-kappaB transcriptional activation after T-cell receptor-mediated stimulation of Jurkat T cells, consistent with its ability to inhibit Jurkat T-cell proliferation and secretion of IL-2. CONCLUSIONS Silymarins ability to inhibit the proliferation and proinflammatory cytokine secretion of T cells, combined with its previously described antiviral effect, suggests a possible mechanism of action that could lead to clinical benefit during HCV infection.

Risk of HIV infection in oral contraceptive pill users: a meta-analysis.

OBJECTIVE To review the literature and present a summary estimate of the association between HIV-1 acquisition or HIV-1 serostatus and oral contraceptives. DATA SOURCES MEDLINE database (January 1986-October 1997), AIDSLINE database (January 1980-October 1997), bibliographies of identified articles, and experts in the field of heterosexual HIV transmission. STUDY SELECTION In all, 591 articles were examined. Twenty-eight studies provided adequate data to calculate a risk estimate for the association of HIV-1 serostatus or HIV-1 seroconversion with oral contraceptives and were selected for inclusion. RESULTS The overall summary odds ratio (OR) for the association between seroprevalent or seroincident HIV-1 infection and use of oral contraceptives in the 28 studies was 1.19 (95% confidence interval [CI], 0.99-1.42). The summary OR for 21 cross-sectional studies was 1.21 (95% CI, 1.01-1.44), whereas the summary relative risk for seven prospective studies was 1.32 (95% CI, 1.12-1.57). Study quality was assessed by applying a scale reflecting study design, measurement of exposure, ability to assess confounding, and publication status. The summary OR for the eight best studies was 1.60 (95% CI, 1.05-2.44). When analysis was limited to studies conducted in Africa, the summary OR was 1.45 (95% CI, 1.15-1.83) for the 14 studies overall, and 1.65 (95% CI, 1.09-2.52) for the seven best studies. CONCLUSION This meta-analysis found a significant association between oral contraceptive use and HIV-1 seroprevalence or seroincidence. For women at risk of HIV-1 infection, oral contraceptive use for prevention of pregnancy should be accompanied by condom use for prevention of HIV-1 infection.

Hepatitis B Virus–Specific and Global T-Cell Dysfunction in Chronic Hepatitis B

BACKGROUND & AIMS T cells play a critical role in viral infection. We examined whether T-cell effector and regulatory responses can define clinical stages of chronic hepatitis B (CHB). METHODS We enrolled 200 adults with CHB who participated in the National Institutes of Health-supported Hepatitis B Research Network from 2011 through 2013 and 20 uninfected individuals (controls). Peripheral blood lymphocytes from these subjects were analyzed for T-cell responses (proliferation and production of interferon gamma and interleukin 10) to overlapping hepatitis B virus (HBV) peptides (preS, S, preC, core, and reverse transcriptase), influenza matrix peptides, and lipopolysaccharide. T-cell expression of regulatory markers FOXP3, programmed death-1, and cytotoxic T lymphocyte-associated antigen-4 was examined by flow cytometry. Immune measures were compared with clinical parameters, including physician-defined immune-active, immune-tolerant, or inactive CHB phenotypes, in a blinded fashion. RESULTS Compared with controls, patients with CHB had weak T-cell proliferative, interferon gamma, and interleukin 10 responses to HBV, with increased frequency of circulating FOXP3(+)CD127(-) regulatory T cells and CD4(+) T-cell expression of programmed death-1 and cytotoxic T lymphocyte-associated antigen-4. T-cell measures did not clearly distinguish between clinical CHB phenotypes, although the HBV core-specific T-cell response was weaker in hepatitis B e antigen (HBeAg)(+) than HBeAg(-) patients (percent responders: 3% vs 23%; P = .00008). Although in vitro blockade of programmed death-1 or cytotoxic T lymphocyte-associated antigen-4 increased T-cell responses to HBV, the effect was weaker in HBeAg(+) than HBeAg(-) patients. Furthermore, T-cell responses to influenza and lipopolysaccharide were weaker in CHB patients than controls. CONCLUSIONS HBV persists with virus-specific and global T-cell dysfunction mediated by multiple regulatory mechanisms, including circulating HBeAg, but without distinct T-cell-based immune signatures for clinical phenotypes. These findings suggest additional T-cell-independent or regulatory mechanisms of CHB pathogenesis that warrant further investigation.