Infection In HIV-positive Men Research Articles

Risk factors of oncogenic HPV infection in HIV-positive men with anal condyloma acuminata in Shenzhen, Southeast China: a retrospective cohort study.

Human immunodeficiency virus (HIV)-positive patients with anal condyloma acuminata (CA) present an increased risk of anal cancer progression associated with oncogenic human papillomavirus (HPV) infection. It is essential to explore determinants of anal infection by oncogenic HPV among HIV-positive patients with CA. A retrospective cohort study was performed in HIV-positive patients with CA between January 2019 to October 2021 in Shenzhen, Southeast China. Exfoliated cells were collected from CA lesions and the anal canal of HPV genotypes detected by fluorescence PCR. Unconditional logistic regression analysis was used to probe associations of independent variables with oncogenic HPV infection. Among HIV-positive patients with CA, the most prevalent oncogenic genotypes were HPV52 (29.43%), HPV16 (28.93%), HPV59 (19.20%), and HPV18 (15.96%). Risk of oncogenic HPV infection increased with age at enrollment (COR: 1.04, 95% CI: 1.01-1.07, p = 0.022). In the multivariable analysis, age ≥ 35 years (AOR: 2.56, 95% CI: 1.20-5.70, p = 0.02) and history of syphilis (AOR: 3.46, 95% CI: 1.90-6.79, p < 0.01) were independent risk factors statistically associated with oncogenic HPV infection. History of syphilis (AOR: 1.72, 95% CI: 1.08-2.73, p < 0.02) was also an independent risk factor statistically associated with HPV16 or HPV18 infection. In clinical practice, HIV-positive CA patients aged ≥35 years or with a history of syphilis should carry out HR-HPV testing and even anal cancer-related examinations to prevent the occurrence of anal cancer.

Oral and anal high-risk human papilloma virus infection in HIV-positive men who have sex with men over a 24-month longitudinal study: complexity and vaccine implications

BackgroundFew studies focused on longitudinal modifications over time of high-risk HPV (HR-HPV) at anal and oral sites in HIV+ men who have sex with men (MSM).MethodsWe described patterns and longitudinal changes of HR-HPV detection and the prevalence of HR-HPV covered by the nonavalent HPV vaccine (vax-HPV) at oral and anal sites in 165 HIV+ MSM followed in an Italian hospital. The samples were collected at baseline and after 24 months (follow-up). The presence of HPV was investigated with Inno-LiPA HPV Genotyping Extra II.ResultsMedian age was 44 years (IQR 36–53), median CD4+ cell count at nadir was 312 cells/mm3 (IQR 187–450). A total of 120 subjects (72.7%) were receiving successful antiretroviral therapy (ART). At baseline and follow-up, the frequency of HR-HPV was significantly higher in the anal site (65.4% vs 9.4 and 62.4% vs 6.8%, respectively). Only 2.9% of subjects were persistently HR-HPV negative at both sites. All oral HR-HPV were single at baseline vs 54.6% at baseline at the anal site (p = 0.005), and all oral HR-HPV were single at follow-up vs 54.4% at anal site at follow-up (p = 0.002). The lowest rate of concordance between the oral and anal results was found for HR-HPV detection; almost all HR-HPV positive results at both anal and oral sites had different HR-HPV.The most frequent HR-HPV in anal swabs at baseline and follow-up were HPV-16 and HPV-52.At follow-up at anal site, 37.5% of patients had different HR-HPV genotypes respect to baseline, 28.8% of subjects with 1 HR-HPV at baseline had an increased number of HR-HPV, and patients on ART showed a lower frequency of confirmed anal HR-HPV detection than untreated patients (p = 0.03) over time. Additionally,54.6 and 50.5% of patients had only HR-vax-HPV at anal site at baseline and follow-up, respectively; 15.2% had only HR-vax-HPV at baseline and follow-up.ConclusionsWe believe that it is important testing multiple sites over time in HIV-positive MSM. ART seems to protect men from anal HR-HPV confirmed detection. Vaccination programmes could reduce the number of HR-HPV genotypes at anal site and the risk of the first HR-HPV acquisition at the oral site.

Anal human papillomavirus infection in HIV-positive men and women at two opportunistic infections clinics in Harare, Zimbabwe

BackgroundHIV-infected individuals are at increased risk of anal cancer; in the majority of cases this is linked to human papillomavirus (HPV) infection. Anal cancer screening is not routinely offered in Zimbabwe.MethodsA cross-sectional study was performed on 152 patients (88 females; 64 males) attending Opportunistic Infection Clinics at 2 tertiary hospitals between November 2014 and June 2015. Demographic data, immunological parameters and behavioural characteristics were collected. An anal swab was collected from each patient for HPV genotype testing. HPV testing was performed using MY09/MY11 PCR, followed by typing using the dot blot method.ResultsThe mean age was 39.6 years (range, 18–69 years). Median CD4 count was 375 cells/μL. 96% were on antiretroviral therapy. Only one patient identified as a man who has sex with men. Of 122 samples tested for HPV, 54 were positive (44%). HPV was three times more common in females (60%) than males (20%). Being HPV-positive was associated with history of perianal warts, history of cervical intraepithelial neoplasia and having more than ten lifetime sexual partners. The most commonly detected high-risk HPV genotypes were HPV-58 (13%), HPV-31 (11%) and HPV-16 (9%). Nine patients harboured multiple high-risk HPV types. The two most commonly detected low-risk genotypes were HPV-11 (17%) and HPV-53 (11%).ConclusionOverall anal HPV prevalence was 44% in this mostly heterosexual HIV-positive population. Oncogenic HPV types accounted for almost half of infections, supporting the need for surveillance of anal cancer in this population.

Are there any challenges left in hepatitis C virus therapy of HIV-infected patients?

Direct-acting antivirals (DAAs) have tremendously improved the treatment of hepatitis C virus (HCV) infections also in human immunodeficiency virus (HIV)-positive individuals. Curing HCV infection is of particular importance in HIV-positive individuals as liver disease progression is accelerated in the course of concomitant HIV infection. Former challenges, such as safety and tolerability as well as reduced treatment uptake of pegylated interferon and ribavirin-based treatments, have been overcome with the approval of DAAs. Indeed, rates of discontinuation under modern all-oral DAA therapy in HIV/HCV coinfection have been reported to be <1%. Rates of sustained virological response (SVR) following treatment have aligned with those seen in HCV monoinfected patients, resulting in an equalisation of treatment recommendations for HCV monoinfected and HIV/HCV coinfected patients. Nevertheless, coinfection with HIV has been associated with slightly higher relapse rates in some real-world cohorts, arousing discussion regarding more individualised treatment once again. Moreover, an ongoing epidemic of acute HCV infections in HIV-positive men who have sex with men with high re-infection rates challenges physicians and researchers. The present review gives a concise summary of the remaining challenges in HCV treatment of HIV-positive individuals.

Prevalence of asymptomatic sexually transmitted infections in HIV-positive men who have sex with men in Germany: results of a multicentre cross-sectional study.

Sexually transmitted infections (STIs) occur frequently in risk populations. Hereby, the role of screening-programmes remains controversial. Our study aimed to determine the prevalence of STI infections in HIV-positive men-who-have-sex-with-men (MSM). We enrolled asymptomatic, HIV-MSM in a prospective cross-sectional study from February to August 2016 at seven German HIV-centres. All subjects were screened for Treponema-pallidum (TP) and hepatitis-B/C-infection. HIV RNA and screening for oral, rectal and urethral colonisation by Chlamydia-trachomatis (CT) and/or Neisseria-gonorrhoeae (NG) was performed. All subjects were asked to complete a sexual-risk-behaviour-questionnaire. In total, 296 subjects with a median age of 43.2 (36.2-49.5) years were enrolled; 99.3% were on ART for 5.5 (2.3-11.2) years. HIV RNA was<50 copies/mL in 93.6%. Active syphilis infection was found in 5.0% of all patients, whereas 55.4% had history of infection. HCV seropositivity was found in 33 patients (13.2%) and positive HCV RNA was available in 39.4%. 66/294 (22.5%) showed negative anti-HBs-antibodies, indicating lack of immunity. Overall, 40/296 (13.5%) had positive CT/NG swabs (CT in 8.8%; 7.3% anorectal, 1.7% oropharyngeal, 1.0% urethral and NG in 6.8%; 4.5% anal, 2.0% oropharyngeal, 1.4% urethral). Time since HIV infection <7years (OR 2.6 (1.2-5.5); p=0.012), the use of inhalative nitrites ("poppers") (OR 2.8 (1.3-5.9; p=0.008) and reporting unprotected intercourse with >20 partners within the last 6months [OR 3.0 (1.2-7.8); p=0.003] were significantly associated in multivariate analysis. We found high numbers of asymptomatic syphilis, hepatitis-C and CT/NG infections in HIV-MSM, remarkably in patients with shorter duration of HIV-infection with more sexual partners within last 6months.

Decrease in Seminal HIV-1 RNA Load After Praziquantel Treatment of Urogenital Schistosomiasis Coinfection in HIV-Positive Men-An Observational Study.

BackgroundUrogenital schistosomiasis due to Schistosoma hematobium infection is hypothesized to cause increased HIV-1 RNA shedding in semen in HIV co-infected men as result of chronic egg-induced inflammation in the prostate and the seminal vesicles. The effect of treatment with the antihelminthic agent praziquantel on seminal HIV-1 RNA load was assessed in this study.MethodsHIV-1 RNA load was determined in blood plasma and semen at baseline and at 10-week follow-up. Praziquantel was administered at baseline and two weeks later.ResultsEighteen HIV-positive men with S. haematobium co-infection were enrolled into the study. Status of antiretroviral therapy (ART): 6 ART-naïve and 12 ART-experienced. All participants became egg-negative in urine at follow-up. Among the ART-naïve men, the mean HIV-1 RNA load decreased by 0.32 log10 copies per mL (4.41 vs 4.09) in blood plasma from baseline to follow-up, and in semen by 1.06 log10 copies per mL (4.06 vs 3.00).ConclusionsThis study demonstrated a decline in seminal HIV-1 RNA load following praziquantel treatment of urogenital schistosomiasis infection in HIV-positive men. The finding needs further exploration in a larger randomized study targeting praziquantel as a supplementary preventive measure of sexual transmission of HIV-1 in S. haematobium endemic areas in sub-Saharan Africa.

Predictors and incidence of sexually transmitted Hepatitis C virus infection in HIV positive men who have sex with men

BackgroundSexual transmission of Hepatitis C virus (HCV) in men who have sex with men (MSM) and its interaction with HIV status, sexually transmitted infections and sexual behaviour is poorly understood. We assessed the incidence and predictors of HCV infection in HIV positive MSM.MethodsThe electronic medical record and laboratory results from HIV positive MSM in care at a large urban public specialist HIV clinic embedded in a sexual health centre in Melbourne Australia were collected. Patients with two or more HCV antibody tests between January 2008 and March 2016 and with no record of injecting drug use were included. The HCV exposure intervals were the periods between a negative HCV test and the next HCV test. We compared HCV exposure intervals temporally associated with and without newly acquired syphilis or anorectal chlamydia. HCV exposure intervals were also categorised as being before or after HIV virological suppression and by most recent and nadir CD4 cell count.ResultsThirty seven new HCV infections were diagnosed in 822 HIV positive MSM with no history of injecting drug use over 3114 person years (PY) of follow-up. Mean age was 43.1 years (±12.5) and mean CD4 cell count nadir was 362 cells/uL (±186). The incidence of HCV infection in the study population was 1.19/100PY (0.99–1.38). The incidence in exposure periods temporally close to new syphilis infection was 4.72/100PY (3.35–6.08) and to new anorectal chlamydia infection was 1.37/100PY (0.81–1.93). The incidence in men without supressed viral load was 3.19/100PY (1.89–4.49). In the multivariate Cox regression analysis only younger age (aHR 0.67 (0.48–0.92)), exposure periods temporally associated to new syphilis infection (aHR 4.96 (2.46–9.99)) and higher CD4 cell count nadir (aHR 1.26 per 100 cells/uL (1.01–1.58)) were associated with increased risk of HCV infection. During the study period the incidence of syphilis increased dramatically but the incidence of HCV infection remained the same.ConclusionsIncidence of HCV infection is associated with syphilis but not anorectal chlamydia which suggests a biological rather than behavioural risk modification. Rising syphilis incidence may offset declines in HCV transmission through HCV treatment as prevention.

Asymptomatic anal sexually transmitted infections in HIV-positive men attending anal cancer screening.

HIV-positive men who have sex with men (HIV+MSM) have an increased risk for anal dysplasia and for sexually transmitted infections (STIs). We determined the positivity rates of Chlamydia trachomatis (CT), Neisseria gonorrhoea (NG), Mycoplasma genitalium (MG) and syphilis in HIV+MSM participating in an anal cancer screening programme. In total, 852 intra-anal swabs were collected from 503 HIV+MSM between 2012 and 2014. Anal cytology and polymerase chain reaction assays for human papillomavirus (HPV), CT, NG and MG detection were performed. The syphilis status was determined serologically. Risk factors for STIs were explored by multiple logistic regression analysis. In total 20·7% (104 of 503) of the patients had an STI other than HPV within the study period. The most common was CT, found in 10·9%, followed by NG (8·9%) and MG (4·2%). Early syphilis was detected in 4·6% and past syphilis in 44·5% of the HIV+MSM. Eighteen patients (3·6%) had more than one STI episode, and 90·6% of the 127 cases of STIs were asymptomatic. Age, anal HPV infection, abnormal anal cytology and previous syphilis were risk factors for STI. Anal STIs are frequent and mostly asymptomatic in HIV+MSM participating in anal cancer screening. STI screening should be incorporated into anal cancer screening programmes for HIV+MSM.

Hepatitis C Virus Awareness Among Men Who Have Sex With Men in Southwest Switzerland.

In Switzerland, the incidence of hepatitis C virus (HCV) infection in HIV-positive men who have sex with men (MSM) rose 18-fold between 1998 and 2011. We aimed to evaluate transmission risk factors, awareness, and seroprevalence of HCV among MSM in southwest Switzerland. From 1st June 2011 to 31st August 2012, trained health care professionals invited individuals attending (1) MSM screening clinics and (2) indoor and outdoor meeting areas to complete an anonymous questionnaire. Consenting participants were rapid tested for HCV (OraQuick HCV Rapid Antibody Test). Of 918 MSM approached, 654 agreed to participate, most of whom (536, 82%) were enrolled via MSM screening clinics. Of 654 participants, 21 (3.2%) disclosed being HIV positive; 140 (21%) had unknown HIV status. In the preceding 12 months, 357 (55%) of 654 participants reported unprotected anal intercourse (UAI) and 321 (49%) of 654 participants reported UAI with partners of different/unknown HIV status. Not HIV serosorting was reported more frequently among HIV-positive individuals (76%, P < 0.001). Three hundred two participants (46%) were aware of HCV, awareness being higher among clinic than meeting area participants (49% vs. 33%, P = 0.04). One individual (of 654; 0.2%), with a negative HIV test result 18 months previously was newly diagnosed as being HCV positive on rapid testing. In this sample of predominantly HIV-negative MSM, half the participants were aware of HCV and HCV seroprevalence was low. However, high rates of UAI and of UAI without HIV serosorting were reported. Given the increasing incidence of HCV among HIV-positive men, we propose that HCV counseling should be offered to MSM regardless of HIV status, with testing offered to those at high risk.

Incidence of sexually transmitted hepatitis C virus infection in HIV-positive men who have sex with men.

The epidemiology of the incidence of sexually transmitted hepatitis C virus (HCV) infection in HIV-positive men who have sex with men (MSM) is only partially understood. In the presence of HIV, HCV infection is more likely to become chronic and liver fibrosis progression is accelerated. A systematic review and meta-analysis was used to synthesize data characterizing sexually transmitted HCV in HIV-positive MSM. Electronic and other searches of medical literature (including unpublished reports) were conducted. Eligible studies reported on HCV seroconversion or on reinfection postsuccessful HCV treatment in HIV-positive MSM who were not injecting drugs. Pooled incidence rates were calculated using random-effects meta-analysis, and meta-regression was used to assess study-level moderators. Attributable risk measures were calculated from statistically significant associations between exposures and HCV seroconversion. More than 13 000 HIV-positive MSM in 17 studies were followed for more than 91 000 person-years between 1984 and 2012; the pooled seroconversion rate was 0.53/100 person-years. Calendar time was a significant moderator of HCV seroconversion, increasing from an estimated rate of 0.42/100 person-years in 1991 to 1.09/100 person-years in 2010, and 1.34/100 person-years in 2012. Reinfection postsuccessful HCV treatment (n = 2 studies) was 20 times higher than initial seroconversion rates. Among the seroconverters, a large proportion of infections were attributable to high-risk behaviours including mucosally traumatic sex and sex while high on methamphetamine. The high reinfection rates and the attributable risk analysis suggest the existence of a subset of HIV-positive MSM with recurring sexual exposure to HCV. Approaches to HCV control in this population will need to consider the changing epidemiology of HCV infection in MSM.

Challenges Presented by Re-Emerging Sexually Transmitted Infections in HIV Positive Men who have Sex with Men: An Observational Study of Lymphogranuloma Venereum in the UK.

BackgroundUnited Kingdom has reported the largest documented outbreak of lymphogranuloma venereum (LGV), a re-emerging sexually transmitted infection (STI) which is primarily seen in HIV-positive men who have sex with men (MSM). A diagnostic service was established in response to the outbreak linked to a voluntary LGV Enhanced Surveillance system. We examined the performance of this novel surveillance system to identify utility in tracking a re-emerging infection.MethodsWe described laboratory data on samples and surveillance data from case reports for LGV from 2004-2010. We performed a cross-sectional analysis comparing clinical and behavioural characteristics of HIV-positive and HIV-negative/unknown LGV cases diagnosed in MSM using multivariable logistic regression models with generalised estimating equations to control for repeat infections.ResultsLGV Surveillance data were available for 87% (1,370/1,581) of LGV cases (after de-duplication). There were 1,342 episodes in 1,281 MSM, most of whom were known to be HIV-positive (1,028/1,281, 80.2%,). HIV-positive men reported a shorter duration of symptoms (aOR 0.5; 95%CI 0.3, 0.8 for reporting more than a week compared to a week or less) in comparison to HIV-negative/unknown MSM, and were more likely to report unprotected receptive anal intercourse (aOR 2.7; 95% CI 1.3, 5.8).ConclusionThe surveillance identified the population at greater risk of infection based on higher levels of risk behaviour in HIV-positive LGV cases. However, there was diagnostic bias towards HIV-positive LGV cases who presented with a shorter duration of symptoms when compared to HIV-negative/unknown LGV cases.

Spontaneous clearance and treatment of acute hepatitis C infection in HIV-positive men with 48 weeks of interferon-alpha and Ribavirin

Acute hepatitis C infection in the context of HIV is an emerging problem in men who have sex with men (MSM). We conducted a retrospective cohort study of MSM diagnosed with and treated for acute hepatitis C infection over 10 years. Genotype 1 was the commonest type representing 69% of cases; the spontaneous clearance rate was 20%. The overall sustained virological response (SVR) rate on an intention-to-treat basis was 83%; SVR and was 92% for those completing 48 weeks of treatment. The presence of detectable RNA at week 12 had a 100% negative predictive value for SVR. This is the largest single cohort treated with 48 weeks of interferon and ribavirin and the treatment SVR is one of the highest reported. We propose that a 48-week treatment regimen may be superior to shorter (24-week) regimens though we acknowledge the need for a randomized controlled trial.

O19 Sexual partnership patterns and sexually transmitted infections in HIV positive men who have sex with men: implications for partner notification

AimsIt is essential to understand the implications of sexual partnerships, sexual networks and type of sexually transmitted infections (STIs) on partner notification to maximise its effectiveness. We examined the relationship...

Tratamiento de la hepatitis por virus C en pacientes coinfectados por el virus de la inmunodeficiencia humana

Hepatitis C virus (HCV)-HIV coinfection currently occurs in more than 30% of HIV-positive patients in Spain. Nowadays, the treatment of choice for chronic hepatitis due to HCV infection in HIV-positive patients is pegylated interferon plus ribavirin. This combination achieves an overall cure rate of 50%, which is somewhat lower than those obtained in patients with HCV monoinfection. Adverse effects are frequent, leading to treatment withdrawal in 10-20% of patients. Importantly, there are three new features of hepatitis C in patients with HIV: (1) the recent development of epidemic outbreaks of acute hepatitis due to HCV infection in HIV-positive men caused by homosexual activity, (2) pharmacogenetic markers in the form of genetic polymorphisms near the IL28B gene related to response to HCV treatment as well as spontaneous eradication of HCV after acute infection, and (3) new antiviral molecules have allowed triple combination treatments to be designed and the preliminary results of clinical trials reporting high response rates are highly promising.

Type-specific human papillomavirus-DNA load in anal infection in HIV-positive men

To characterize anal human papillomavirus (HPV) infections in terms of genotype prevalence and type-specific DNA load in HIV-positive men. HIV-positive men attending the colo-proctological clinic of a University Hospital in Rome were recruited prospectively from November 2004 to July 2007. HIV-negative outpatients attending the same clinic over the same period were used as a control group. Anal brushings were tested for HPV-DNA using polymerase chain reactions and direct sequencing; type-specific HPV-DNA copies were measured in most positive samples. HPV data were correlated with patient HIV status and risk factors. HPV-DNA infection was detected in 81% of HIV-positive men. Almost all homosexual men were HPV-infected. The infection rate in low-risk HPV types was higher than in high-risk types. The spectrum of HPV genotypes was comparable between HIV-positive and HIV-negative men. Numbers of HPV-DNA copies varied greatly between samples but did not differ significantly between HIV-positive and HIV-negative men. In many samples, low-risk (HPV 6, 61, 70, and 74) viral loads were comparable with those of high-risk HPVs. Type-specific HPV-DNA copies at baseline appear to be independent of patient immune status and of HPV genotype. HPV genotype risk and viral load should be further evaluated for their potential predictive role in persistence and progression.

Acute hepatitis C infection in HIV positive men who have sex with men in Paris, France, 2001-2004.

In mid-2004, three Parisian hospital wards informed the Institut de veille sanitaire of recent acute hepatitis C in HIV-infected (HIV+) men who had sex with men (MSM). These cases for whom none of the usual bloodborne routes for hepatitis C (HCV) transmission was found, reported having had unprotected sex. In October 2004, we conducted a retrospective investigation in Parisian hospital wards to explore HCV modes of transmission in recent acute hepatitis C in HIV+ MSM. Patient demographics, clinical and biological status of HIV infection, reasons for HCV testing, sexual behaviour and risk factors for HCV transmission within the 6 months before hepatitis onset were collected from medical records. An anonymous self-administered questionnaire on sexual behaviour within the six months before hepatitis onset was also offered to all cases. We identified 29 cases of acute hepatitis C in HIV+ MSM with onset from April 2001 to October 2004. HIV infection was asymptomatic for 76%. Median age at hepatitis C onset was 40 (28-54) years. In all records, were noted unprotected anal sex, fisting in 21% and a concomitant sexually transmitted infection (STI) in 41%. Median time between HIV diagnosis and HCV infection was 6.5 years (0-22). From the 11 self-administered questionnaires completed, 10 reported an STI, 8 "hard" sexual practices, 6 bleeding during sex and 5 fisting. HCV transmission probably occurred through bleeding during unprotected traumatic anal sex among HIV+ MSM and may be facilitated by STI mucosal lesions. This report stresses the continuous need to strongly advocate safer sex to MSM.

Stress-associated reductions of cytotoxic T lymphocytes and natural killer cells in asymptomatic HIV infection

Previous research has documented a possible relation of stress and depression to cell-mediated immunity. The authors examined how stressful events and depression may affect key parameters of cellular immunity in subjects with and without HIV infection. Data were collected on 99 asymptomatic HIV-positive and 65 HIV-negative homosexual men as part of an ongoing, longitudinal study. Criticisms of previous studies of psychoimmunity were addressed by 1) using a comprehensive, semistructured interview to measure the objective context of stressful events, 2) double labeling of lymphocytes with monoclonal antibodies to measure subsets of cytotoxic/suppressor T lymphocytes and natural killer (NK) cells, and 3) controlling for circadian effects and methodological factors. In the HIV-positive men, severe stress was significantly associated with reductions in NK cell populations and a subset of T cells thought to represent cytotoxic T effector cells, particularly the CD8+ T cells expressing the CD57 antigen. In the HIV-negative men, no clear and consistent relation between stress and immune system measures was found. Depression was not correlated with any variables in either of the groups, perhaps due to the low levels of depressive symptoms. The findings suggest that stress is associated with reductions in killer lymphocytes (decreased NK cell and cytotoxic T lymphocyte phenotypes). The data provide evidence that stress may alter cell populations that provide cytotoxic defense against infection in HIV-positive men and indicate that the clinical significance of stress-related changes in cytotoxic T lymphocytes and NK cells in HIV infection warrants further study.