Impact of HIV infection and Kaposi sarcoma on human herpesvirus-8 mucosal replication and dissemination in Uganda

Increased frequency and quantity of mucosal and plasma cytomegalovirus replication among Ugandan Adults Living with HIV

BACKGROUND

Co-infection with HIV can result in impaired control of cytomegalovirus (CMV) replication, increasing the likelihood of disease and onward transmission. The objective of this analysis was to measure the impact of HIV on CMV replication in an intensively-sampled cohort in Kampala, Uganda.

METHODS

CMV seropositive men and women aged 18-65, with or without HIV co-infection, were followed for one month. Daily oral swabs and weekly anogenital swabs and plasma were collected. Quantitative CMV PCR was performed on all samples.

RESULTS

Eighty-five participants were enrolled and provided ≥1 oral swab; 43 (51%) were HIV-seropositive. People living with HIV (PLWH; median CD4 count 439 cells/mm3; none on antiretrovirals) had 2-4 times greater risk of CMV detection at each anatomical site assessed. At the oral site, 773 of 1272 (61%) of samples from PLWH had CMV detected, compared to 214 of 1349 (16%) among people without HIV. Similarly, the mean CMV quantity was higher among PLWH at all anatomical sites, with the largest difference seen for oral swabs (mean difference 1.63 log/mL; 95% CI 1.13-2.13). Among PLWH, absolute quantity of CD4+ T-cells was not associated with risk of CMV detection. HIV plasma RNA quantity was positively correlated with oral CMV shedding frequency, but not detection at other sites.

CONCLUSIONS

Mucosal and systemic CMV replication occurs at higher levels in PLWH than people without HIV, particularly oral shedding, which is a major mode of CMV transmission. Increased CMV replication despite relatively preserved CD4+ T-cell counts suggests that additional interventions are required to improve CMV control in PLWH.

A prospective study of clinical outcomes of HIV-associated and HIV-negative Kaposi sarcoma in Uganda

OBJECTIVE

Improved understanding of the effect of HIV infection on Kaposi sarcoma (KS) presentation and outcomes will guide development of more effective KS staging and therapeutic approaches. We enrolled a prospective cohort of epidemic (HIV-positive; HIV + KS) and endemic (HIV-negative; HIV - KS) KS patients in Uganda to identify factors associated with survival and response.

METHODS

Adults with newly diagnosed KS presenting for care at the Uganda Cancer Institute (UCI) in Kampala, Uganda, between October 2012 and December 2019 were evaluated. Participants received chemotherapy per standard guidelines and were followed over 1 year to assess overall survival (OS) and treatment response.

RESULTS

Two hundred participants were enrolled; 166 (83%) had HIV + KS, and 176 (88%) were poor-risk tumor (T1) stage. One-year OS was 64% (95% confidence interval [CI] 57-71%), with the hazard of death nearly threefold higher for HIV + KS (hazard ratio [HR] = 2.93; P  = 0.023). Among HIV + KS, abnormal chest X-ray (HR = 2.81; P  = 0.007), lower CD4 + T-cell count (HR = 0.68 per 100 cells/μl; P  = 0.027), higher HIV viral load (HR = 2.22 per log 10  copies/ml; P  = 0.026), and higher plasma Kaposi sarcoma-associated herpesvirus (KSHV) copy number (HR = 1.79 per log 10  copies/ml; P  = 0.028) were associated with increased mortality. Among HIV - KS, factors associated with mortality included Karnofsky score <70 (HR = 9.17; P  = 0.045), abnormal chest X-ray (HR = 8.41; P  = 0.025), and higher plasma KSHV copy number (HR = 6.21 per log 10  copies/ml; P  < 0.001).

CONCLUSIONS

Although survival rates were better for HIV - KS than HIV + KS, the high mortality rate seen in both groups underscores the urgent need to identify new staging and therapeutic approaches. Factors associated with mortality, including high plasma KSHV, may serve as important targets of therapy.

KSHV (HHV8) vaccine: promises and potential pitfalls for a new anti-cancer vaccine

Seven viruses cause at least 15% of the total cancer burden. Viral cancers have been described as the "low-hanging fruit" that can be potentially prevented or treated by new vaccines that would alter the course of global human cancer. Kaposi sarcoma herpesvirus (KSHV or HHV8) is the sole cause of Kaposi sarcoma, which primarily afflicts resource-poor and socially marginalized populations. This review summarizes a recent NIH-sponsored workshop's findings on the epidemiology and biology of KSHV as an overlooked but potentially vaccine-preventable infection. The unique epidemiology of this virus provides opportunities to prevent its cancers if an effective, inexpensive, and well-tolerated vaccine can be developed and delivered.

Characterization of Adaptive-like γδ T Cells in Ugandan Infants during Primary Cytomegalovirus Infection

Gamma-delta (γδ) T cells are unconventional T cells that help control cytomegalovirus (CMV) infection in adults. γδ T cells develop early in gestation, and a fetal public γδ T cell receptor (TCR) clonotype is detected in congenital CMV infections. However, age-dependent γδ T cell responses to primary CMV infection are not well-understood. Flow cytometry and TCR sequencing was used to comprehensively characterize γδ T cell responses to CMV infection in a cohort of 32 infants followed prospectively from birth. Peripheral blood γδ T cell frequencies increased during infancy, and were higher among CMV-infected infants relative to uninfected. Clustering analyses revealed associations between CMV infection and activation marker expression on adaptive-like Vδ1 and Vδ3, but not innate-like Vγ9Vδ2 γδ T cell subsets. Frequencies of NKG2C⁺CD57⁺ γδ T cells were temporally associated with the quantity of CMV shed in saliva by infants with primary infection. The public γδ TCR clonotype was only detected in CMV-infected infants <120 days old and at lower frequencies than previously described in fetal infections. Our findings support the notion that CMV infection drives age-dependent expansions of specific γδ T cell populations, and provide insight for novel strategies to prevent CMV transmission and disease.

What to Do for Increasing Cancer Burden on the African Continent? Accelerating Public Health Diagnostics Innovation for Prevention and Early Intervention on Cancers

No other place illustrates the increasing burden of cancer than in Africa and in particular, sub-Saharan Africa. Many of the individuals to be diagnosed with cancer will be in low-resource settings in the future due to, for example, an increase in populations and aging, and high co-morbidity with infections with viruses such as human immunodeficiency virus (HIV) and human papillomavirus (HPV), as well as the presence of infectious agents linked to cancer development. Due to lack of prevention and diagnostic innovation, patients present with advanced cancers, leading to poor survival and increased mortality. HIV infection-associated cancers such as B cell lymphomas, Kaposi's sarcoma, and HPV-associated cancers such as cervical cancer are particularly noteworthy in this context. Recent reports show that a host of other cancers are also associated with viral infection and these include lung, oral cavity, esophageal, and pharyngeal, hepatocellular carcinoma, and anal and vulvar cancers. This article examines the ways in which diagnostic innovation empowered by integrative biology and informed by public health priorities can improve cancer prevention or early intervention in Africa and beyond. In addition, I argue that because diagnostic biomarkers can often overlap with novel therapeutic targets, diagnostics research and development can have broader value for and impact on medical innovation.

Examining the dynamics of Epstein-Barr virus shedding in the tonsils and the impact of HIV-1 coinfection on daily saliva viral loads

Epstein-Barr virus (EBV) is transmitted by saliva and is a major cause of cancer, particularly in people living with HIV/AIDS. Here, we describe the frequency and quantity of EBV detection in the saliva of Ugandan adults with and without HIV-1 infection and use these data to develop a novel mathematical model of EBV infection in the tonsils. Eligible cohort participants were not taking antiviral medications, and those with HIV-1 infection had a CD4 count >200 cells/mm3. Over a 4-week period, participants provided daily oral swabs that we analysed for the presence and quantity of EBV. Compared with HIV-1 uninfected participants, HIV-1 coinfected participants had an increased risk of EBV detection in their saliva (IRR = 1.27, 95% CI = 1.10-1.47) and higher viral loads in positive samples. We used these data to develop a stochastic, mechanistic mathematical model that describes the dynamics of EBV, infected cells, and immune response within the tonsillar epithelium to analyse potential factors that may cause EBV infection to be more severe in HIV-1 coinfected participants. The model, fit using Approximate Bayesian Computation, showed high fidelity to daily oral shedding data and matched key summary statistics. When evaluating how model parameters differed among participants with and without HIV-1 coinfection, results suggest HIV-1 coinfected individuals have higher rates of B cell reactivation, which can seed new infection in the tonsils and lower rates of an EBV-specific immune response. Subsequently, both these traits may explain higher and more frequent EBV detection in the saliva of HIV-1 coinfected individuals.

Intra-host changes in Kaposi sarcoma-associated herpesvirus genomes in Ugandan adults with Kaposi sarcoma

Intra-host tumor virus variants may influence the pathogenesis and treatment responses of some virally-associated cancers. However, the intra-host variability of Kaposi sarcoma-associated herpesvirus (KSHV), the etiologic agent of Kaposi sarcoma (KS), has to date been explored with sequencing technologies that possibly introduce more errors than that which occurs in the viral population, and these studies have only studied variable regions. Here, full-length KSHV genomes in tumors and/or oral swabs from 9 Ugandan adults with HIV-associated KS were characterized. Furthermore, we used deep, short-read sequencing using duplex unique molecular identifiers (dUMI)–random double-stranded oligonucleotides that barcode individual DNA molecules before library amplification. This allowed suppression of PCR and sequencing errors to ~10⁻⁹/base as well as afforded accurate determination of KSHV genome numbers sequenced in each sample. KSHV genomes were assembled de novo, and rearrangements observed were confirmed by PCR and Sanger sequencing. 131-kb KSHV genome sequences, excluding major repeat regions, were successfully obtained from 23 clinical specimens, averaging 2.3x10⁴ reads/base. Strikingly, KSHV genomes were virtually identical within individuals at the point mutational level. The intra-host heterogeneity that was observed was confined to tumor-associated KSHV mutations and genome rearrangements, all impacting protein-coding sequences. Although it is unclear whether these changes were important to tumorigenesis or occurred as a result of genomic instability in tumors, similar changes were observed across individuals. These included inactivation of the K8.1 gene in tumors of 3 individuals and retention of a region around the first major internal repeat (IR1) in all instances of genomic deletions and rearrangements. Notably, the same breakpoint junctions were found in distinct tumors within single individuals, suggesting metastatic spread of rearranged KSHV genomes. These findings define KSHV intra-host heterogeneity in vivo with greater precision than has been possible in the past and suggest the possibility that aberrant KSHV genomes may contribute to aspects of KS tumorigenesis. Furthermore, study of KSHV with use of dUMI provides a proof of concept for utilizing this technique for detailed study of other virus populations in vivo.

Kaposi sarcoma (KS) is a leading cancer in sub-Saharan Africa and in persons with HIV co-infection. Kaposi sarcoma-associated herpesvirus (KSHV, also referred to as human herpesvirus-8, or HHV-8) is the etiologic agent of KS, but the factors that contribute to the development of KS, which occurs in only a small subset of infected individuals, remain largely unknown. While strain differences or mutations in other tumor viruses are known to affect the risk and progression of their associated cancers, whether genetic variation in KSHV is important to the natural history of KS is unclear. Most studies of KSHV diversity have only characterized ~4% of its 165-kb genome, and the observed variation in some studies is likely to have been impacted by PCR or cloning artifacts. To precisely define genomic diversity of KSHV in vivo, we evaluated full-length viral genomes (except the internal repeat regions) using a technique that greatly lowers sequencing error rates and thus measures genomic diversity much more accurately than previous studies. In addition, we extended our analyses to look for potential tumor-specific changes in the KSHV genomes by examining viruses in both tumor and non-tumor tissues. To these ends, we performed highly sensitive, single-molecule sequencing of whole KSHV genomes in paired KS tumors and oral swabs from 9 individuals with KS. We found that KSHV genomes were virtually identical within the 9 individuals, with no evidence of quasispecies formation or multi-strain infection. However, KSHV genome aberrations and gene-inactivating mutations were found to be common in KS tumors, often impacting the same genes and genomic regions across individuals. Whether theses mutations influence KS tumorigenesis or result from genomic instability commonly found in tumors warrants further study. Lastly, aberrant KSHV genomes were found to be shared by distinct tumors within individuals, suggesting the capacity of KS tumor cells to metastasize and seed new lesions.

Seroepidemiology of the human herpesvirus 8 infection among people living with HIV in Taiwan, 2014-2018

BACKGROUND

Human herpesvirus type 8 (HHV-8) can be transmitted through unprotected sex as HIV. We aimed to investigate the seroincidence of HHV-8 and associated factors among people living with HIV (PLWH).

METHODS

From 2014 to 2018, blood samples of PLWH on the first date of HIV care were determined for antibodies against HHV-8. Individuals testing HHV-8-seronegative at baseline were followed for at least four months to estimate the annual seroconversion rate. To identify the factors associated with HHV-8 seroconversion, we compared the clinical characteristics between seroconverters and non-seroconverters who were matched for observation duration.

RESULTS

The HHV-8 seroprevalence increased from 8.1% in 2014 to 20.0% in 2018. HHV-8 seroconversion occurred in 154 (14.7%) PLWH after a total of 2652.16 person-years of follow-up (PYFU), resulting in an overall incidence rate of 5.62 per 100 PYFU, which increased from 3.20 to 6.84 per 100 PYFU during the study period. HHV-8 seroconverters were less likely to have chronic hepatitis B virus (HBV) infection (1.9% vs 10.6%) and more likely to be antiretroviral-naïve on entry into care (87.7% vs 75.4%) (both p < 0.05). In multivariate logistic analysis, men who have sex with men (MSM) (adjusted odds ratio [aOR], 2.22; 95% CI, 1.01-4.86), being antiretroviral-naïve (aOR, 2.91; 95% CI, 1.27-6.67), and chronic HBV infection (aOR, 0.13; 95% CI, 0.03-0.61) at baseline were associated with HHV-8 seroconversion.

CONCLUSIONS

An increasing trend of HHV-8 infection was observed among PLWH in Taiwan between 2014 and 2018. MSM and being antiretroviral-naïve were associated with higher risk for HHV-8 seroconversion.

Estimating the Risk of Human Herpesvirus 6 and Cytomegalovirus Transmission to Ugandan Infants from Viral Shedding in Saliva by Household Contacts

Human herpesvirus 6 (HHV-6) and cytomegalovirus (CMV) infections are common in early childhood. In a prospective Ugandan birth cohort study, most infants acquired HHV-6 (24/31; 77%) and CMV (20/30; 67%) during follow-up. To assess the transmission risk, we modeled a dose-response relationship between infant HHV-6 and CMV infections and weekly oral viral shedding by mothers and all other ("secondary") children in the home. Oral viral loads that were shed by mothers and secondary children were significantly associated with HHV-6 but not CMV transmission. While secondary children had higher and more frequent HHV-6 shedding than their mothers, they had a lower per-exposure transmission risk, suggesting that transmission to maternal contacts may be more efficient. HHV-6 transmission was relatively inefficient, occurring after <25% of all weekly exposures. Although HHV-6 transmission often occurs following repeated, low dose exposures, we found a non-linear dose-response relationship in which infection risk markedly increases when exposures reached a threshold of > 5 log₁₀ DNA copies/mL. The lack of association between oral CMV shedding and transmission is consistent with breastfeeding being the dominant route of infant infection for that virus. These affirm saliva as the route of HHV-6 transmission and provide benchmarks for developing strategies to reduce the risk of infection and its related morbidity.

BALB/c mice immunized with a combination of virus-like particles incorporating Kaposi sarcoma-associated herpesvirus (KSHV) envelope glycoproteins gpK8.1, gB, and gH/gL induced comparable serum neutralizing antibody activity to UV-inactivated KSHV

Infection with Kaposi sarcoma-associated herpesvirus (KSHV) is estimated to account for over 44,000 new cases of Kaposi sarcoma annually, with 84% occurring in Africa, where the virus is endemic. To date, there is no prophylactic vaccine against KSHV. KSHV gpK8.1, gB, and gH/gL glycoproteins, implicated in the virus entry into host cells, are attractive vaccine targets for eliciting potent neutralizing antibodies (nAbs) against virus infection. We incorporated gpK8.1, gB, or gH/gL on the surface of virus-like particles (VLPs) and characterized these VLPs for their composition, size, and functionality. To determine which viral glycoprotein(s) elicit the most effective serum-nAbs, we immunized BALB/c mice with gpK8.1, gB, or gH/gL VLPs individually or in combination. Neutralizing antibody assay revealed that sera from mice immunized with the VLPs inhibited KSHV infection of HEK-293 cells in a dose-dependent manner. As a single immunogen, gpK8.1 VLPs stimulated comparable nAb activity to that of UV-inactivated KSHV (UV-KSHV). In contrast, UV-KSHV stimulated higher titers of nAb compared to gB (p = 0.0316) or gH/gL (p = 0.0486). Mice immunized with the combination of gB and gH/gL VLPs had a better nAb response than those immunized with either gB (p = 0.0268), or gH/gL (p = 0.0397) as single VLP immunogens. Immunization with any VLP combination stimulated comparable nAb activity to UV-KSHV serum. Our data provide the first evidence that KSHV gpK8.1, gB, and gH/gL glycoproteins can be incorporated onto the surface of VLPs and used as prophylactic vaccine candidates, with potential to prevent KSHV infection.

Omega-3 decreases IL-6 levels in HIV and human herpesvirus-8 coinfected patients in Uganda

OBJECTIVE

Kaposi sarcoma is a HIV-associated malignancy caused by human herpesvirus-8 (HHV-8) that occurs at highest incidence in sub-Saharan Africa. Kaposi sarcoma patients often present with inflammatory symptoms associated with higher mortality.

DESIGN

We conducted a double-blind, randomized, placebo-controlled study in Uganda to test whether omega-3 supplementation could reduce inflammation in HIV and HHV-8 coinfected adults. Patients with acute illness, AIDS, or advanced Kaposi sarcoma were ineligible, as were pregnant women. Participant IDs were pre-randomized, blocked by Kaposi sarcoma status, to either the omega-3 or placebo arm.

METHODS

Omega-3 participants received a 3-g pill dose daily for 12 weeks (1.8-g eicosapentaenoic acid, 1.2-mg docosapentaenoic acid); placebo participants received 44.8 mg of high oleic safflower oil that appeared indistinguishable from the active supplement. Intervention effects were evaluated as the baseline-adjusted mean difference after 12 weeks between omega-3 and placebo participants in concentrations of fatty acids, inflammatory cytokines, and immune cells.

RESULTS

The final study population included 56 Kaposi sarcoma patients and 11 Kaposi sarcoma-negative, HIV and HHV-8-positive participants randomized to receive either omega-3 (N = 33) or placebo (N = 34). Inflammatory cytokine IL-6 concentrations decreased in omega-3 participants (-0.78 pg/ml) but increased in placebo participants (+3.2 pg/ml; P = 0.04). We observed a trend toward decreased IL-6 after omega-3 supplementation specific to Kaposi sarcoma patients (P = 0.08). CD8 T-cell counts tended to increase in the omega-3 arm Kaposi sarcoma patients (+60 cells/μl), in contrast to decreases (-47 cells/μl) among placebo (P = 0.11).

CONCLUSION

Omega-3 supplementation decreased IL-6 concentrations among HIV and HHV-8 coinfected Ugandans, which may have clinical benefit for Kaposi sarcoma patients.

KSHV oral shedding and plasma viremia result in significant changes in the extracellular tumorigenic miRNA expression profile in individuals infected with the malaria parasite

Kaposi's sarcoma herpesvirus (KSHV) is the etiological agent of Kaposi’s sarcoma (KS). Both KSHV and HIV infections are endemic in Uganda, where KS is among the most common cancers in HIV-infected individuals. Recent studies examined the use of small RNAs as biomarkers of disease, including microRNAs (miRNAs), with viral and tumor-derived miRNAs being detected in exosomes from individuals with KSHV-associated malignancies. In the current study, the host and viral extracellular mature miRNA expression profiles were analyzed in blood of KS-negative individuals in Uganda, comparing those with or without KSHV detectable from the oropharynx. We observed increased levels of cellular oncogenic miRNAs and decreased levels of tumor-suppressor miRNAs in plasma of infected individuals exhibiting oral KSHV shedding. These changes in host oncomiRs were exacerbated in people co-infected with HIV, and partially reversed after 2 years of anti-retroviral therapy. We also detected KSHV miRNAs in plasma of KSHV infected individuals and determined that their expression levels correlated with KSHV plasma viremia. Deep sequencing revealed an expected profile of small cellular RNAs in plasma, with miRNAs constituting the major RNA biotype. In contrast, the composition of small RNAs in exosomes was highly atypical with high levels of YRNA and low levels of miRNAs. Mass spectrometry analysis of the exosomes revealed eleven different peptides derived from the malaria parasite, Plasmodium falciparum, and small RNA sequencing confirmed widespread plasmodium co-infections in the Ugandan cohorts. Proteome analysis indicated an exosomal protein profile consistent with erythrocyte and keratinocyte origins for the plasma exosomes. A strong correlation was observed between the abundance of Plasmodium proteins and cellular markers of malaria. As Plasmodium falciparum is an endemic pathogen in Uganda, our study shows that co-infection with other pathogens, such as KSHV, can severely impact the small RNA repertoire, complicating the use of exosome miRNAs as biomarkers of disease.

Prospective study of human herpesvirus 8 oral shedding, viremia, and serological status among human immunodeficiency virus seropositive and seronegative individuals in Sao Paulo, Brazil

Human herpesvirus 8 (HHV-8) is a gamma-herpesvirus and etiological agent of all forms of Kaposi sarcoma (KS). Saliva may play an important role in HHV-8 transmission in specific populations. Little is known about HHV-8 oral shedding pattern and the possible correlation with the HHV-8 serological profile and viremia. A prospective study was conducted of HHV-8 salivary excretion among human immunodeficiency virus HIV-seronegative (n = 47) and -seropositive (n = 44) homosexual men and HIV-seropositive women (n = 32) over a 6-month period with monthly HHV-8 serologies (immunofluorescence assays to identify antibodies to latent and lytic HHV-8 viral proteins, and a whole-virus HHV-8 enzyme-linked immunosorbent assay [ELISA]), monthly HHV-8 DNA serum/plasma detection, and daily self-collected oral rinses for HHV-8-DNA detection using real-time polymerase chain reaction. HHV-8 seropositivity was 51.1%, 63.6%, and 37.5%, in the three studied groups. There was no case of HHV-8 DNA detection in serum/plasma. Intermittent detection of oral HHV-8 DNA was observed during 5.1% (110/2,160) of visits among 28% (18/64) of HHV-8-seropositive individuals, all of whom were males and HHV-8 ELISA seropositive. In immunologically controlled populations of Brazil, HHV-8 oral shedding was limited to HHV-8-seropositive men, occurred infrequently and intermittently, and was not linked to HHV-8 viremia, suggesting a limited potential for oral or blood transmission.

Detection of Human Herpes Virus 8 in Kaposi's sarcoma tissues at the University Teaching Hospital, Lusaka, Zambia

INTRODUCTION

Human herpes virus-8, a γ2-herpes virus, is the aetiological agent of Kaposi sarcoma. Recently, Kaposi's sarcoma cases have increased in Zambia. However, the diagnosis of this disease is based on morphological appearance of affected tissues using histological techniques, and the association with its causative agent, Human Herpes virus 8 is not sought. This means poor prognosis for affected patients since the causative agent is not targeted during diagnosis and KS lesions may be mistaken for other reactive and neoplastic vascular proliferations when only histological techniques are used. Therefore, this study was aimed at providing evidence of Human Herpes virus 8 infection in Kaposi's sarcoma tissues at the University Teaching Hospital in Lusaka, Zambia.

METHODS

One hundred and twenty suspected Kaposi's sarcoma archival formalin-fixed paraffin-wax embedded tissues stored from January 2013 to December 2014 in the Histopathology Laboratory at the University Teaching Hospital, Lusaka, Zambia were analysed using histology and Polymerase Chain Reaction targeting the ORF26 gene of Human Herpes virus 8.

RESULTS

The predominant histological type of Kaposi's sarcoma detected was the Nodular type (60.7%) followed by the plaque type (22.6%) and patch type (16.7%). The nodular lesion was identified mostly in males (40.5%, 34/84) than females (20.2%, 17/84) (p=0.041). Human Herpes virus 8 DNA was detected in 53.6% (45/84) and mostly in the nodular KS lesions (60%, 27/84) (p=0.035).

CONCLUSION

The findings in this study show that the Human Herpes virus-8 is detectable in Kaposi's sarcoma tissues, and, as previously reported in other settings, is closely associated with Kaposi's sarcoma. The study has provided important baseline data for use in the diagnosis of this disease and the identification of the virus in the tissues will aid in targeted therapy.

Predictors of seropositivity for human herpesvirus type 8 in patients with mild cirrhosis

The high seroprevalence of human herpesvirus type 8 (HHV-8) in moderate or severe cirrhotics appears to be associated with male sex, hepatitis B virus (HBV) infection, alcoholism, and disease severity. The status of HHV-8 infection in mild cirrhotics remains unclear. Plasma samples collected from 93 mild cirrhotics and 93 age- and sex-matched healthy controls were analyzed for HHV-8 antibody and HHV-8 DNA. Mild cirrhotics had higher seropositivity for HHV-8 antibodies than healthy controls (P=0.0001). Univariate logistic regression analysis revealed that an age ≥55 years (odds ratio (OR) 2.88, P=0.02), hepatitis C virus (HCV) infection (OR 3.42, P=0.01), and hepatitis activity (OR 4.10, P=0.004) were associated with HHV-8 seropositivity in cirrhotics. Stepwise multivariate logistic regression analysis confirmed that age ≥55 years (adjusted OR (aOR) 1.92, P=0.04) and hepatitis activity (aOR 3.55, P=0.005) were independent factors. The rate of hepatitis activity was higher in HCV-infected than in HBV-infected patients (P<0.0001) and in women than in men (P=0.0001). Cirrhotics who were seropositive for HHV-8 or HCV or had hepatitis activity were significantly older (P=0.02, <0.0001 and <0.0001, respectively). Plasma samples from all participants were negative for HHV-8 DNA. HHV-8 antibody titers in mild cirrhotics also markedly exceeded those in controls (P<0.0001), as did those in patients ≥55 years old vs. younger patients (P=0.01), those in patients with vs. without HCV infection (P=0.0008), and those in patients with vs. without hepatitis activity (P=0.0005). Mild cirrhotics had high HHV-8 seroprevalence and HCV infection, and, in particular, old age and hepatitis activity were predictors.

Dynamics of Persistent Oral Cytomegalovirus Shedding During Primary Infection in Ugandan Infants

Cytomegalovirus (CMV) infection occurs frequently in young children, who, when infected, are then a major source of transmission. Oral CMV shedding by 14 infants with primary infection was comprehensively characterized using quantitative polymerase chain reaction weekly for ≥9 months. Three phases of oral shedding were identified: expansion, transition, and clearance. Viral expansion occurred over a median of 7 weeks, with a median doubling time of 3 days. During the transition phase, expansion slowed over a median of 6 weeks before peak viral load was reached. Clearance was slow (22-day median half-life), and shedding did not resolve during observation for any infant. Mathematical modeling demonstrated that prolonged oral CMV expansion is explained by a low within-host reproduction number (median, 1.63) and a delayed immune response that only decreases the infected cell half-life by 44%. Thus, the prolonged oral CMV shedding observed during primary infection can be explained by slow viral expansion and inefficient immunologic control.

Prospective Characterization of the Risk Factors for Transmission and Symptoms of Primary Human Herpesvirus Infections Among Ugandan Infants

BACKGROUND

Human herpesvirus (HHV) infections are common during infancy. Primary infections are frequently asymptomatic and best studied prospectively by using direct viral detection.

METHODS

Oropharyngeal swab specimens were collected weekly from Ugandan newborn infants, their mothers, and other children in the household. Blood specimens were collected every 4 months. Samples were tested for herpes simplex virus (HSV) types 1 and 2, Epstein-Barr virus (EBV), cytomegalovirus (CMV), HHV-6A, HHV-6B, and HHV-8, using quantitative polymerase chain reaction.

RESULTS

Thirty-two infants, 32 mothers, and 49 other household children were followed for a median of 57 weeks. Seventeen mothers had human immunodeficiency virus type 1 (HIV) infection; no infants acquired HIV-1. The 12-month incidence of postnatal infection was 76% for HHV-6B, 59% for CMV, 47% for EBV, 8% for HSV-1, and 0% for HHV-8. The quantity of oropharyngeal shedding by contacts was associated with HHV-6A or HHV-6B transmission. Maternal HIV-1 infection was associated with EBV transmission, while breastfeeding and younger child contacts were associated with CMV transmission. Except for HSV-1, primary HHV infections were subclinical.

CONCLUSIONS

By capturing exposures and acquisition events, we found that the incidence and risk factors of infection vary by HHV type. HSV-1 infection, unlike other HHV infections, caused acute clinical illness in these infants.

Patterns of human herpesvirus-8 oral shedding among diverse cohorts of human herpesvirus-8 seropositive persons

Background

Human herpesvirus-8 (HHV-8), the etiologic agent of Kaposi sarcoma (KS), establishes lifelong latent infection with periodic lytic replication (“shedding”) at mucosal sites, especially the oropharynx. Patterns of HHV-8 shedding are not well understood, and require elucidation to better predict risk of HHV-8 related malignancies in those infected. We sought to characterize patterns of HHV-8 oropharyngeal shedding among diverse cohorts that enrolled HHV-8 seropositive persons.

Methods

We quantified HHV-8 oral shedding using PCR among HHV-8 seropositive persons who collected at least 14 days of oral swabs in 22 studies on 3 continents. We excluded persons taking antivirals during sampling or any prior use of antiretrovirals in those who were HIV-infected.

Results

248 participants were enrolled from the US, Peru, Cameroon, Uganda, and Kenya; 61 % were men, 58 % were HIV seropositive, and 16 % had KS. Overall, 3,123 of 10,557 samples (29.6 %) had HHV-8 detected. Quantity of virus shed was highly correlated with shedding rate, (ρ = 0.72, p < 0.0001). HHV-8 was detected in ≥1 sample in 55 % of participants with a median of 7 % of days in the US and Kenya, 0 % in Uganda and Peru, and 18 % in Cameroon. Median episode duration was three days, and episodes with high median quantity lasted longer (42 vs 3 days, p < 0.0001). In persons with multiple observations over time, 66 % of shedding rate variance was attributable to differences between individuals.

Conclusions

In HHV-8 infected individuals from diverse settings, oral mucosal shedding rate, quantity, and duration were correlated; individual shedding was highly variable. Studies are needed to determine factors accounting for between-person variation and the relationship of HHV-8 shedding to development of associated diseases.

Cancer prevention in HIV-infected populations

People living with human immunodeficiency virus (HIV) are living longer since the advent of effective combined antiretroviral therapy (cART). While cART substantially decreases the risk of developing some cancers, HIV-infected individuals remain at high risk for Kaposi sarcoma, lymphoma, and several solid tumors. Currently HIV-infected patients represent an aging group, and malignancies have become a leading cause of morbidity and mortality. Tailored cancer-prevention strategies are needed for this population. In this review we describe the etiologic agents and pathogenesis of common malignancies in the setting of HIV, as well as current evidence for cancer prevention strategies and screening programs.

Diagnostic challenges of oral and cutaneous Kaposi's sarcoma in resource-constrained settings

OBJECTIVES

Kaposi's sarcoma (KS), caused by HHV-8, is the most frequent HIV-associated malignancy worldwide and remains a major scourge in Sub-Saharan Africa. KS is also endemic in much of Africa. There is a risk of misdiagnosis based solely on clinical appearance and haematoxylin and eosin (H&E) staining, especially with other reactive and neoplastic vascular proliferations which occur in the mouth. This study examined oral and cutaneous biopsies from clinically diagnosed lesions of KS in Kenya, using histopathology supplemented with immunohistochemistry (IHC) and polymerase chain reaction (PCR) for HHV-8 as confirmation of diagnosis.

METHODS

Biopsies of 49 lesions (28 oral, 21 cutaneous) previously diagnosed as 'KS' were re-examined by H&E staining and IHC targeting HHV-8 LANA-1. Positive controls were sections from embedded BCBL-1 cell lines. Negative controls were from three different HHV-8-negative biopsies. Confirmation of HHV-8 immunohistochemistry was sought by PCR and by determining the HHV-8 ORFK1 subtype.

RESULTS

Whilst most cases were confirmed, 12 oral and 4 cutaneous lesions displayed clinical and histological features of KS but were negative to HHV-8 IHC. These oral lesions were re-diagnosed as pyogenic granulomata (n = 6), deep mycosis (n = 1), inflamed mucosa (n = 2) or 'uncertain but not KS' (n = 3). Whilst PCR is usually helpful in differentiating HHV-8 disease, all samples were HHV-8 PCR positive, with identical sequences, suggesting cross-contamination of samples in the original pathology laboratories.

CONCLUSION

HHV-8 IHC is essential for the correct diagnosis of KS, but due to the high level of contamination in resource-poor settings, PCR is inadvisable.

Viral profiling identifies multiple subtypes of Kaposi's sarcoma

Kaposi’s sarcoma (KS), caused by KS-associated herpesvirus (KSHV), is the most common cancer among HIV-infected patients in Malawi and in the United States today. In Malawi, KSHV is endemic. We conducted a cross-sectional study of patients with HIV infection and KS with no history of chemo- or antiretroviral therapy (ART). Seventy patients were enrolled. Eighty-one percent had T1 (advanced) KS. Median CD4 and HIV RNA levels were 181 cells/mm³ and 138,641 copies/ml, respectively. We had complete information and suitable plasma and biopsy samples for 66 patients. For 59/66 (89%) patients, a detectable KSHV load was found in plasma (median, 2,291 copies/ml; interquartile range [IQR], 741 to 5,623). We utilized a novel KSHV real-time quantitative PCR (qPCR) array with multiple primers per open reading frame to examine KSHV transcription. Seventeen samples exhibited only minimal levels of KSHV mRNAs, presumably due to the limited number of infected cells. For all other biopsy samples, the viral latency locus (LANA, vCyc, vFLIP, kaposin, and microRNAs [miRNAs]) was transcribed abundantly, as was K15 mRNA. We could identify two subtypes of treatment-naive KS: lesions that transcribed viral RNAs across the length of the viral genome and lesions that displayed only limited transcription restricted to the latency locus. This finding demonstrates for the first time the existence of multiple subtypes of KS lesions in HIV- and KS-treatment naive patients.

KS is the leading cancer in people infected with HIV worldwide and is causally linked to KSHV infection. Using viral transcription profiling, we have demonstrated the existence of multiple subtypes of KS lesions for the first time in HIV- and KS-treatment-naive patients. A substantial number of lesions transcribe mRNAs which encode the viral kinases and hence could be targeted by the antiviral drugs ganciclovir or AZT in addition to chemotherapy.

A MATHEMATICAL MODEL FOR THE TREATMENT OF AIDS-RELATED KAPOSI'S SARCOMA

We formulate a mathematical model to study the dynamics of HIV-1 related Kaposi's Sarcoma (KS) pathogenesis. KS progression is modeled as a dual process involving the primary infection of B cells, which sustains HHV-8 replication and the secondary infection of progenitor cells by HHV-8, which sustains the KS cell replication. We incorporate the pharmacodynamics of highly active antiretroviral therapy (HAART), or combination therapy (HAART plus KS therapy) and consider how each treatment strategy alters the disease progression. Our results indicate that administration of HAART to individuals co-infected with the HIV-1 and HHV-8 viruses can greatly amplify the therapeutic response of low-dose KS therapies. We have found that adherence levels above 85% can significantly reduce the risk of KS and HIV for a treatment periods under 1 year. For longer treatment periods, however, at least 90% adherence level is recommended.

Building capacity for sustainable research programmes for cancer in Africa

Cancer research in Africa will have a pivotal role in cancer control planning in this continent. However, environments (such as those in academic or clinical settings) with limited research infrastructure (laboratories, biorespositories, databases) coupled with inadequate funding and other resources have hampered African scientists from carrying out rigorous research. In September 2012, over 100 scientists with expertise in cancer research in Africa met in London to discuss the challenges in performing high-quality research, and to formulate the next steps for building sustainable, comprehensive and multi-disciplinary programmes relevant to Africa. This was the first meeting among five major organizations: the African Organisation for Research and Training in Africa (AORTIC), the Africa Oxford Cancer Foundation (AfrOx), and the National Cancer Institutes (NCI) of Brazil, France and the USA. This article summarizes the discussions and recommendations of this meeting, including the next steps required to create sustainable and impactful research programmes that will enable evidenced-based cancer control approaches and planning at the local, regional and national levels.

Oral HHV-8 replication among women in Mombasa, Kenya

Human herpesvirus-8 (HHV-8) replication in the oropharynx may play an important role in HHV-8 transmission and contribute to the development of Kaposi sarcoma (KS) in some individuals. Studies in the United States and Europe report high rates of HHV-8 DNA detection in saliva of HHV-8 infected men, but little is known about the natural history of HHV-8 among persons in sub-Saharan Africa, where prevalence of HHV-8 infection and KS is greatest. To address this gap, this study evaluated oral HHV-8 replication in a cohort of 40 HHV-8 seropositive Kenyan women. Study clinicians collected daily oral swabs from participants for up to 30 consecutive days, and swab samples were tested for HHV-8 DNA using quantitative, real-time polymerase chain reaction. HHV-8 was detected at least once in 27 (68%) participants, and the overall shedding rate was 23%. On days with HHV-8 detection, mean HHV-8 quantity was 4.5 log10  copies/ml. Among HIV-infected women, CD4 count ≥500 cells/mm(3) versus <500 cells/mm(3) was associated with higher HHV-8 copy number (4.8 log10  copies/ml vs. 3.4 log10  copies/ml; coef 1.2 [95% CI, 0.5-1.9]; P = 0.001) and a higher HHV-8 shedding rate (49% vs.12%; RR, 4.2 [95% CI, 0.8-21.4]; P = 0.08). No other factors were associated with HHV-8 shedding rate or copy number. The study demonstrates high rates and quantity of HHV-8 in the oropharynx of HHV-8 seropositive African women. These findings support the observation that oral replication is an essential feature of HHV-8 infection, with likely implications for HHV-8 transmission and KS pathogenesis.

Reduced human herpesvirus-8 oropharyngeal shedding associated with protease inhibitor-based antiretroviral therapy

BACKGROUND

Human herpesvirus 8 (HHV-8) replication increases the risk of Kaposi sarcoma (KS). Highly-active antiretroviral therapy (HAART) reduces the incidence of KS, and regimens that contain protease inhibitors (PIs) may be particularly effective.

OBJECTIVE

To determine whether PI-based HAART regimens may more effectively inhibit HHV-8 shedding compared to regimens without PIs.

STUDY DESIGN

Prospective, observational study of 142 HIV-1 and HHV-8 co-infected men conducted in Seattle, Washington. Quantitative HHV-8 PCR testing was performed on daily swabs of the oropharynx, the primary site of HHV-8 replication. Associations between antiretroviral regimen and detection of HHV-8 DNA in swabs were evaluated using generalized estimating equations.

RESULTS

HHV-8 DNA was detected in 3016 (26%) of 11,608 specimens collected. PI-based HAART was associated with a statistically significantly lower frequency of detection (RR 0.2; 95% CI 0.1-0.5) compared to ART-naïve persons, whereas HAART without a PI was not (RR 0.7; 95% CI 0.4-1.3). Compared to ART-naïve persons, there was also a trend toward lower quantities of HHV-8 detected during treatment with HAART regimens that contained a PI. These associations between PIs and measures of HHV-8 shedding could not be attributed to use of nelfinavir, which inhibits HHV-8 replication in vitro, and were independent of CD4 count and HIV plasma viral load (VL).

CONCLUSIONS

HAART regimens that contain PIs appear to decrease HHV-8 shedding compared to NNRTIs. Further study of PI-based HAART is warranted to determine the optimal regimens for prevention and treatment of KS.

Population-based assessment of kaposi sarcoma-associated herpesvirus DNA in plasma among Ugandans

Risk of Kaposi sarcoma (KS) is linked to detection of Kaposi sarcoma-associated herpesvirus (KSHV) DNA in plasma, but little is known about the prevalence and risk factors for plasma KSHV DNA detection among the general population where KS is endemic. Correlates of KSHV plasma detection were investigated in a population-based sample of adult Ugandans (15-59 years) who participated in an HIV/AIDS serobehavioral survey in 2004/2005. KSHV DNA was measured in plasma of 1,080 KSHV seropositive and 356 KSHV seronegative persons using polymerase chain reaction (PCR). KSHV DNA in plasma was detected in 157 (8.7%) persons; of these 149 (95%) were KSHV seropositive and 8 (5%) were seronegative. Detection of KSHV DNA in plasma was significantly associated with male sex (P < 0.001), older age (P = 0.003), residence in a rural versus urban area (P = 0.002), geographic region (P = 0.02), and being KSHV seropositive (13.8% seropositive vs. 2.3% seronegative, P < 0.001). In a multivariable model, KSHV DNA plasma quantity was significantly higher in men (P = 0.002), inversely associated with age (P = 0.05), and residing in an urban area (P = 0.01). In Uganda, KSHV is detected more frequently in the plasma of adult males and residents of rural regions, potentially explaining the increased risk of KS in these subsets of the Ugandan population.

Higher levels of neutralizing antibodies against KSHV in KS patients compared to asymptomatic individuals from Zambia

Kaposi sarcoma-associated herpesvirus (KSHV) is the etiologic agent for Kaposi Sarcoma (KS), the most common cancer diagnosed in HIV- infected patients. The role of neutralizing antibodies in KS pathogenesis and in KSHV infected individuals is not clearly understood. The goal of this study was to investigate and compare the prevalence and titers of neutralizing antibodies in plasma samples from KS patients and KSHV infected asymptomatic individuals from Zambia, a KS endemic region in sub-Saharan Africa. Plasma samples (N = 267) consisting of KS patients (group 1) and asymptomatic individuals (group 2) were collected from Lusaka, Zambia. A flow cytometry based quantitative neutralization assay utilizing recombinant KSHV expressing GFP was used to detect KSHV neutralizing antibodies. Our results show that the overall prevalence of neutralizing antibodies in KS patients (group 1) was 66.7% which was significantly higher than the prevalence of 6.5% present in KSHV infected asymptomatic individuals (group 2). Total antibody titers as well as neutralizing antibodies titers were found to be significantly higher among KS patients. It is likely that higher neutralizing antibodies prevalence and titers in KS patients result from higher levels of antigenic stimulation over time. This study is first to compare prevalence and titers of neutralizing antibodies in participants with and without disease from a KSHV endemic region.

Anogenital Lesions: Kaposi's Sarcoma and Its Mimicks

Kaposi's sarcoma (KS) is a low-grade vascular neoplasm associated with human herpes virus-8 (HHV-8) infection, and, in the epidemic form, with the human immunodeficiency virus (HIV). Although HHV-8 is present in all body fluids and is sexually transmitted, there are surprisingly few reports of anogenital KS. Clinically, especially in HIV/KS endemic areas, dark stained skin patches or nodules are prone to misdiagnosis, especially in dark-skinned individuals. Therefore, a biopsy is recommended. The histologic appearance spans a broad spectrum of KS and non-KS lesions; therefore, the final diagnosis should be confirmed by HHV-8 immunohistochemistry. We report a series of 36 anogenital biopsies from a group of 16 documented HIV-positive patients; in 20 the HIV serostatus was unknown. There were ten KS (five in HIV-positive patients), and 26 non-KS (11 in HIV-positive subjects) lesions. In the era of HIV/AIDS, anogenital lesions may be the first manifestation of KS in immunocompromised individuals and should be biopsied. The histological diagnosis should be confirmed by HHV-8 immunohistochemistry.

Human herpesviruses 6, 7, and 8 from a dermatologic perspective

Human herpesviruses (HHVs) have frequently been suspected as etiologic agents or cofactors in cutaneous disease. However, clearly established associations are rare. Investigations into an etiologic association between HHVs and cutaneous disease are complicated by the ubiquity and nearly universal prevalence of some herpesviruses. This article summarizes the associations between cutaneous disease and HHV-6, HHV-7, and HHV-8. In addition to a personal library of references, the PubMed database of biomedical literature was searched using the following Medical Subject Heading terms: HHV-6, HHV-7, and HHV-8, each in conjunction with cutaneous manifestations, virology, epidemiology, dermatopathology, and therapeutics, between 1998 and March 2011. Free-text searches with known or suspected disease associations were added for broader coverage. The results have been summarized to provide a practical review for the physician likely to encounter cutaneous diseases.

Vaccine prospect of Kaposi sarcoma-associated herpesvirus

Infection of Kaposi sarcoma-associated herpesvirus (KSHV) or human herpesvirus-8 (HHV-8) is estimated to account for 34,000 new cancer cases globally. Unlike other herpesviruses, KSHV is not ubiquitous but is highly prevalent in some areas, such as sub-Saharan Africa where Kaposi sarcoma is the leading cancer among adults. While latent infection of KSHV plays a major and direct role in tumorigenesis, viral lytic replication also makes significant contributions to this process. Efforts to develop a KSHV vaccine are limited, but studies with EBV have provided important lessons. Informative vaccine research has been conducted in the mouse infection model of a closely related rodent virus, murine gammaherpesvirus-68 (MHV-68 or γHV-68). This mouse model has generated fundamental principles for an effective vaccination strategy. KSHV vaccines designed to prevent a naïve host from infection and to boost the immune control of KSHV in persistently infected people will have major impact on individuals who are at a high risk of developing KSHV-associated diseases.

Treatment with valacyclovir, famciclovir, or antiretrovirals reduces human herpesvirus-8 replication in HIV-1 seropositive men

Human herpesvirus-8 (HHV-8) replication is a key factor in Kaposi sarcoma, primary effusion lymphoma, and Castleman disease pathogenesis. In vitro data suggest that antivirals inhibit HHV-8 replication, but little data exist in humans. Daily oropharyngeal swabs were analyzed from HIV/HHV-8 dually infected men enrolled in three previous clinical trials of valacyclovir and famciclovir for HIV-1 and/or HSV-2 suppression. Fifty-eight participants contributed 6,036 swabs. HHV-8 was detected in 1,128 (19%) of 6,036 swabs, including 618 (21%) of 2,992 on placebo, 323 (15%) of 2,221 on valacyclovir, and 187 (23%) of 823 on famciclovir. After adjusting for baseline HIV viral load and highly active antiretroviral therapy (HAART) use, an 18% reduction in HHV-8 shedding frequency (IRR 0.822; P = 0.011) was found in participants on valacyclovir and a 30% reduction (IRR 0.700; P < 0.001) on famciclovir. HAART was associated with an 89% (IRR 0.129; P = 0.048) reduction in HHV-8-shedding. Neither antiviral nor antiretroviral therapy was associated with decreased HHV-8 quantity. Valacyclovir and famciclovir were associated with modest but significant reductions in HHV-8 oropharyngeal shedding frequency. In contrast, HAART was a potent inhibitor of HHV-8 replication. Studies of whether antiviral therapy in combination with ART will prevent HHV-8-associated disease appear warranted.

KSHV DNA viremia correlates with low CD4+ cell count in Italian males at the time of diagnosis of HIV infection

To evaluate the relevance and the virological and immunological markers of Kaposi sarcoma herpesvirus 8 (KSHV) viremia in Italian male patients at the time of diagnosis of infection with HIV-1, 481 men infected with HIV were recruited consecutively. The presence of KSHV DNA was evaluated in peripheral blood mononuclear cells (PBMCs) and in plasma and correlated with demographic and viro-immunological parameters. Seventy-four patients had KSHV DNA detected in PBMCs. By univariate analysis, the presence of KSHV DNA was associated significantly with unprotected homosexual relationships (P=0.003) and it was significantly higher in patients with CD4+ cell <350 (P=0.025). By multivariate analysis, homosexual relationships were associated independently with KSHV DNA in PBMCs (OR: 3.25; 95% CI: 1.1-9.7; P=0.035). Among the 74 patients with KSHV DNA detected in PBMCs, plasma samples from 60 were analyzed and 33 were positive for KSHV DNA. The CD4+ cell counts and percentages were significantly lower in patients with KSHV DNA in both PBMCs and plasma as compared to patients with only KSHV DNA in PBMCs (P=0.006 and P=0.019, respectively). Among the patients with KSHV DNA detected in PBMCs, all 13 patients with CD4+ cells count <200 had detectable levels of KSHV in their plasma. By multivariate analysis adjusted for the epidemiologic and virological parameters, low CD4+ cell count was the only independent variable associated with the presence of KSHV DNA in plasma (OR, 0.001; 95% CI: <0.001-0.001; P=0.03). In HIV-positive antiretroviral therapy-naïve males, KSHV active replication as detected by KSHV DNA in plasma was associated significantly with low CD4+ cell count.

The Infectious Diseases Institute at Makerere University, Kampala, Uganda

The Infectious Diseases Institute (IDI) at Makerere University, Kampala, Uganda, was created in 2001. This article outlines its origins, principles, clinical programs, training activities, research programs, organizational structure, leadership, and contributions to Makerere University and its College of Health Sciences.

Human herpesvirus 8-associated neoplasms: the roles of viral replication and antiviral treatment

PURPOSE OF REVIEW

In this review, we highlight the importance of human herpesvirus 8 (HHV-8) lytic replication and the potential for antiviral therapies to prevent or treat HHV-8-related neoplasms.

RECENT FINDINGS

Diseases caused by HHV-8 infection include Kaposi sarcoma, multicentric Castleman disease (MCD), and primary effusion lymphoma (PEL), which occur primarily in patients with HIV infection. Kaposi sarcoma is the most common AIDS-associated malignancy worldwide. MCD and PEL occur less commonly but, like Kaposi sarcoma, are associated with poor treatment outcomes. Like all herpesviruses, HHV-8 is capable of either latent or lytic infection of cells. Although HHV-8 infection of tumor cells is predominately latent, accumulating data point to the importance of both lytic phase viral gene products and production of infectious virus. Antiviral agents that target herpesvirus DNA synthesis, such as ganciclovir, inhibit HHV-8 lytic replication and can prevent Kaposi sarcoma. Several HIV protease inhibitors may interfere with tumor growth and angiogenesis, and one protease inhibitor, nelfinavir, directly inhibits HHV-8 replication in vitro.

SUMMARY

Controlled trials are indicated to determine the clinical utility of antiviral suppression of HHV-8 replication, and identify the optimal antiretroviral regimens, for the prevention and treatment of Kaposi sarcoma.

The increasing burden of HIV-associated malignancies in resource-limited regions

Cancer is increasingly recognized as a complication of HIV infection in both resource-rich and resource-limited areas. The traditional AIDS-defining cancers, including Kaposi sarcoma, cervical cancer, and non-Hodgkin lymphoma, have become common comorbidities afflicting HIV-positive individuals and lack adequate prevention and management options. Additionally, several non-AIDS-defining cancers have increased in incidence in resource-limited regions, including Hodgkin lymphoma, hepatocellular carcinoma, and lung cancer. This review outlines the epidemiology of HIV-associated malignancies in resource-poor and resource-rich areas, including the impact of highly active antiretroviral therapy on the incidence of these cancers. The pathogenesis of HIV-associated cancers is considered in relation to potential strategies for their prevention and treatment.

Gender differences in clinical presentation and outcomes of epidemic Kaposi sarcoma in Uganda

Introduction

The incidence of Kaposi sarcoma (KS) has increased dramatically among women in sub-Saharan Africa since the onset of the HIV pandemic, but data on KS disease in women are limited. To identify gender-related differences in KS presentation and outcomes, we evaluated the clinical manifestations and response in men and women with AIDS-associated KS in Uganda.

Methods and Findings

HIV-infected adults with KS attending the Infectious Diseases Institute (IDI) and Uganda Cancer Institute (UCI) in Kampala, Uganda between 2004 and 2006 were included in a retrospective cohort. Evaluation of KS presentation was based on the clinical features described at the initial KS visit. Response was evaluated as the time to “improvement”, as defined by any decrease in lesion size, lesion number, or edema. The cohort consisted of 197 adults with HIV and KS: 55% (108/197) were women. At presentation, the median CD4 T-cell count was significantly lower in women (58 cells/mm³; IQR 11–156 cells/mm³) than men (124 cells/mm³; IQR 22–254 cells/mm³) (p = 0.02). Women were more likely than men to present with lesions of the face (OR 2.8, 95% CI, 1.4, 5.7; p = 0.005) and hard palate (OR 2.0, 95% CI, 1.1, 3.7; p = 0.02), and were less likely than men to have lower extremity lesions (OR 0.54, 95% CI, 0.3, 0.99; p = 0.05). Women were less likely than men to demonstrate clinical improvement (HR = 0.52, CI 0.31, 0.88; p = 0.01) in multivariate analysis.

Conclusions

The clinical presentation and response of KS differs between men and women in Uganda. These data suggest that gender affects the pathophysiology of KS, which may have implications for the prevention, diagnosis, and treatment of KS in both men and women. Prospective studies are needed to identify predictors of response and evaluate efficacy of treatment in women with KS, particularly in Africa where the disease burden is greatest.

Kaposi's sarcoma in sub-Saharan Africa: a current perspective

PURPOSE OF REVIEW

The aim of this review is to summarize the most recent published literature on HIV/AIDS Kaposi's sarcoma in sub-Saharan Africa (SSA). We attempted to update readers on the epidemiology of Kaposi's sarcoma herpesvirus infection and HIV Kaposi's sarcoma in SSA, as well as clinical features, therapy and immune reconstitution inflammatory syndrome associated with HIV Kaposi's sarcoma.

RECENT FINDINGS

Seroprevalence rates of Kaposi's sarcoma herpesvirus differ across SSA; it is low in South African children as compared to endemic areas like Uganda. The major route of transmission in SSA is horizontal rather than sexual. The incidence of Kaposi's sarcoma has increased exponentially with the HIV/AIDS pandemic with a shift in trend demonstrating a dramatic increase in females and occurrence in younger individuals. Kaposi's sarcoma specific therapy is underutilized due to poor access to highly active antiretroviral therapy and financial constraints in SSA. As highly active antiretroviral therapy becomes available, clinicians treating HIV/AIDS in SSA need to have a high index of suspicion of Kaposi's sarcoma immune reconstitution inflammatory syndrome events.

SUMMARY

Kaposi's sarcoma is a public health concern in SSA. More studies appropriate to therapy for Kaposi's sarcoma in resource-poor environments like SSA are imperative. We are hopeful that with the increased availability of highly active antiretroviral therapy, the incidence of HIV Kaposi's sarcoma will decrease and management will improve, as it has in the West.

Persistence of HIV-1 receptor-positive cells after HSV-2 reactivation is a potential mechanism for increased HIV-1 acquisition

To explore the mechanism behind the association between HSV-2 and HIV-1 acquisition, we performed in situ analysis of the cellular infiltrate from sequential biopsies of HSV-2 lesions on and off antiviral therapy. CD4⁺ and CD8⁺ T cells, and a mixed population of plasmacytoid and myeloid dendritic cells (DCs), including cells expressing DC-SIGN, persisted at sites of HSV-2 reactivation for months after healing, even in the context of daily antiviral therapy. The CD4⁺ T cells that persisted reacted to HSV-2 antigen, were enriched for CCR5 expression, and were also contiguous to DCs expressing CD123 or DC-SIGN. Ex vivo infection with a CCR5-tropic strain of HIV-1 revealed increased concentrations of integrated HIV-1 DNA in cells derived from healed genital lesion biopsies as compared to control skin biopsies. The persistence and enrichment of HIV-receptor-positive inflammatory cells in the genitalia help explain the failure of anti-HSV-2 therapy to reduce HIV acquisition.