T Cell Activation in South African HIV-Exposed Infants Correlates with Ochratoxin A Exposure

The introduction of non-breastmilk foods to HIV-infected infants is associated with increased levels of immune activation, which can impact the rate of HIV disease progression. This is particularly relevant in countries where mother-to-child transmission of HIV still occurs at unacceptable levels. The goal of this study was to evaluate the levels of the toxic food contaminant ochratoxin A (OTA) in HIV-exposed South African infants that are either breastfed or consuming non-breast milk foods. OTA is a common mycotoxin, found in grains and soil, which is toxic at high doses but has immunomodulatory properties at lower doses. Samples from HIV-exposed and HIV-unexposed infants enrolled in prospective observational cohort studies were collected and analyzed at birth through 14 weeks of age. We observed that infants consuming non-breast milk foods had significantly higher plasma levels of OTA at 6 weeks of age compared to breastfed infants, increasing until 8 weeks of age. The blood levels of OTA detected were comparable to levels observed in OTA-endemic communities. OTA plasma levels correlated with HIV target cell activation (CCR5 and HLADR expression on CD4+ T cells) and plasma levels of the inflammatory cytokine CXCL10. These findings provide evidence that elevated OTA levels in South African infants are associated with the consumption of non-breastmilk foods and activation of the immune system. Reducing infant OTA exposure has the potential to reduce immune activation and provide health benefits, particularly in those infants who are HIV-exposed or HIV-infected.

Microbial Composition Predicts Genital Tract Inflammation and Persistent Bacterial Vaginosis in South African Adolescent Females

Young African females are at an increased risk of HIV acquisition, and genital inflammation or the vaginal microbiome may contribute to this risk. We studied these factors in 168 HIV-negative South African adolescent females aged 16 to 22 years. Unsupervised clustering of 16S rRNA gene sequences revealed three clusters (subtypes), one of which was strongly associated with genital inflammation. In a multivariate model, the microbiome compositional subtype and hormonal contraception were significantly associated with genital inflammation. We identified 40 taxa significantly associated with inflammation, including those reported previously (Prevotella, Sneathia, Aerococcus, Fusobacterium, and Gemella) as well as several novel taxa (including increased frequencies of bacterial vaginosis-associated bacterium 1 [BVAB1], BVAB2, BVAB3, Prevotella amnii, Prevotella pallens, Parvimonas micra, Megasphaera, Gardnerella vaginalis, and Atopobium vaginae and decreased frequencies of Lactobacillus reuteri, Lactobacillus crispatus, Lactobacillus jensenii, and Lactobacillus iners). Women with inflammation-associated microbiomes had significantly higher body mass indices and lower levels of endogenous estradiol and luteinizing hormone. Community functional profiling revealed three distinct vaginal microbiome subtypes, one of which was characterized by extreme genital inflammation and persistent bacterial vaginosis (BV); this subtype could be predicted with high specificity and sensitivity based on the Nugent score (≥9) or BVAB1 abundance. We propose that women with this BVAB1-dominated subtype may have chronic genital inflammation due to persistent BV, which may place them at a particularly high risk for HIV infection.

Converging epidemics of sexually transmitted infections and bacterial vaginosis in southern African female adolescents at risk of HIV

Adolescents in Africa are at high risk for HIV infection, other sexually transmitted infections (STIs) and bacterial vaginosis (BV). Since behavior and burden of STIs/BV may influence HIV risk, behavioral risk factors and prevalence of STIs/BV were compared in HIV-seronegative adolescent females (n = 298; 16-22 years) from two South African communities (Soweto and Cape Town). STIs ( Chlamydia trachomatis, Neisseria gonorrhoeae, Trichomonas vaginalis, Mycoplasma genitalium, herpes simplex virus (HSV)-1, HSV-2, Treponema pallidum, and Haemophilus ducreyi) were detected by multiplex polymerase chain reaction, human papillomavirus (HPV) by Roche Linear Array, and BV by Nugent scoring. Rates of BV (Nugent ≥7; 46.6%) and HPV (66.8%) were high in both communities. Prevalence of C. trachomatis and N. gonorrhoeae were >2-fold higher in Cape Town than Soweto (Chlamydia: 42% [62/149] versus 18% [26/148], p < 0.0001; gonorrhoea 11% [17/149] versus 5% [7/148], p = 0.05). Only 24% of adolescents with vaginal discharge-causing STIs or BV were symptomatic. In South African adolescents, clinical symptoms compatible with vaginal discharge syndrome had a sensitivity of 23% and specificity of 85% for the diagnosis of discharge-causing STI or BV. In a region with high HIV prevalence and incidence, >70% of young women with treatable conditions that could enhance HIV risk would have been missed because they lacked symptoms associated with syndromic management.

CCR5 expression, haplotype and immune activation in protection from infection in HIV-exposed uninfected individuals in HIV-serodiscordant relationships

Several host factors have been implicated in resistance to HIV infection in individuals who remain HIV-seronegative despite exposure. In a cohort of HIV-serodiscordant heterosexual couples, we investigated interactions between systemic inflammation and T-cell activation in resistance to HIV infection. Males and females in stable long-term relationships with either HIV-infected or uninfected partners were recruited, blood T-cell activation (CD38, HLA-DR, CCR5 and Ki67) and plasma cytokine concentrations were evaluated. The HIV-negative exposed individuals had significantly lower frequencies of CCR5⁺ CD4⁺ and CD8⁺ T cells than unexposed individuals. Mean fluorescence intensity of CCR5 expression on CD4⁺ T cells was significantly lower in HIV-negative exposed than unexposed individuals. Protective CCR5 haplotypes (HHA/HHF*2, HHF*2/HHF*2, HHC/HHF*2, HHA/HHA, HHA/HHC and HHA/HHD) tended to be over-represented in exposed compared with unexposed individuals (38% versus 28%, P = 0·58) whereas deleterious genotypes (HHC/HHD, HHC/HHE, HHD/HHE, HHD/HHD and HHE/HHE) were under-represented (26% versus 44%; P = 0·16). Plasma concentrations of interleukin-2 (P = 0·02), interferon-γ (P = 0·05) and granulocyte-macrophage colony-stimulating factor (P = 0·006) were lower in exposed compared with unexposed individuals. Activation marker expression and systemic cytokine concentrations were not influenced by gender. We conclude that the dominant signature of resistance to HIV infection in this cohort of exposed but uninfected individuals was lower T-cell CCR5 expression and plasma cytokine concentrations.

BCG vaccination induces HIV target cell activation in HIV-exposed infants in a randomized trial

BACKGROUND. Bacillus Calmette-Guérin (BCG) vaccine is administered at birth to protect infants against tuberculosis throughout Africa, where most perinatal HIV-1 transmission occurs. We examined whether BCG vaccination alters the levels of activated HIV target T cells in HIV-exposed South African infants. METHODS. HIV-exposed infants were randomized to receive routine (at birth) or delayed (at 8 weeks) BCG vaccination. Activated and CCR5-expressing peripheral blood CD4⁺ T cell, monocyte, and NK cell frequencies were evaluated by flow cytometry and immune gene expression via PCR using Biomark (Fluidigm). RESULTS. Of 149 infants randomized, 92% (n = 137) were retained at 6 weeks: 71 in the routine BCG arm and 66 in the delayed arm. Routine BCG vaccination led to a 3-fold increase in systemic activation of HIV target CD4⁺CCR5⁺ T cells (HLA-DR⁺CD38⁺) at 6 weeks (0.25% at birth versus 0.08% in delayed vaccination groups; P = 0.029), which persisted until 8 weeks of age when the delayed arm was vaccinated. Vaccination of the infants in the delayed arm at 8 weeks resulted in a similar increase in activated CD4⁺CCR5⁺ T cells. The increase in activated T cells was associated with increased levels of MHC class II transactivator (CIITA), IL12RB1, and IFN-α1 transcripts within peripheral blood mononuclear cells but minimal changes in innate cells. CONCLUSION. BCG vaccination induces immune changes in HIV-exposed infants, including an increase in the proportion of activated CCR5⁺CD4⁺ HIV target cells. These findings provide insight into optimal BCG vaccine timing to minimize the risks of HIV transmissions to exposed infants while preserving potential benefits conferred by BCG vaccination. TRIAL REGISTRATION. ClinicalTrials.gov NCT02062580. FUNDING. This trial was sponsored by the Elizabeth Glaser Pediatric AIDS Foundation (MV-00-9-900-01871-0-00) and the Thrasher Foundation (NR-0095); for details, see Acknowledgments.

Probiotics for vaginal health in South Africa: what is on retailers' shelves?

BACKGROUND

Probiotics are widely used to improve gastrointestinal (GI) health, but they may also be useful to prevent or treat gynaecological disorders, including bacterial vaginosis (BV) and candidiasis. BV prevalence is high in South Africa and is associated with increased HIV risk and pregnancy complications. We aimed to assess the availability of probiotics for vaginal health in retail stores (pharmacies, supermarkets and health stores) in two major cities in South Africa.

METHODS

A two-stage cluster sampling strategy was used in the Durban and Cape Town metropoles. Instructions for use, microbial composition, dose, storage and manufacturers' details were recorded.

RESULTS

A total of 104 unique probiotics were identified in Cape Town and Durban (66.4% manufactured locally). Cape Town had more products than Durban (94 versus 59 probiotics), although 47% were common between cities (49/104). Only four products were explicitly for vaginal health. The remainder were for GI health in adults (51.0%) or infants (17.3%). The predominant species seen overall included Lactobacillus acidophilus (53.5%), L. rhamnosus (37.6%), Bifidobacterium longum ssp. longum (35.6%) and B. animalis ssp. lactis (33.7%). Products for vaginal health contained only common GI probiotic species, with a combination of L. acidophilus/B. longum ssp. longum/B. bifidum, L. rhamnosus/L. reuteri or L. rhamnosus alone, despite L. crispatus, L. gasseri, and L. jensenii being the most common commensals found in the lower female reproductive tract.

CONCLUSION

This survey highlights the paucity of vaginal probiotics available in South Africa, where vaginal dysbiosis is common. Most vaginal products contained organisms other than female genital tract commensals.

Afri-Can Forum 2

A1 Introduction to the 2nd synchronicity forum of GHRI/CHVI-funded Canadian and African HIV prevention and vaccine teams

O1 Voluntary medical male circumcision for prevention of heterosexual transmission of HIV in adult males in Soweto: What do indicators and incidence rate show?

Hillary Mukudu, Neil Martinson, Benn Sartorius

O2 Developing a peer-led community mobilization program for sex workers in Soweto: HIV risk and demographics

Jenny Coetzee, Janan Dietrich, Kgaugelo Mokgatswana, Rachel Jewkes, Glenda E. Gray

O3 Salient beliefs about adherence: A qualitative survey conducted as part of the demonstration study on "treatment as prevention" (TasP) and "pre-exposure prophylaxis" (PrEP) among female sex workers (FSWS) in Cotonou, Benin

Marylène Dugas, Luc Béhanzin, Fernand A. Guédou, Marie-Pierre Gagnon, Michel Alary

O4 Relative perception of risk as a driver of unsafe sexual practices among key populations: Cases of fisherfolk and women and their partners involved in multiple sexual partnerships in Uganda

Rwamahe Rutakumwa, Martin Mbonye, Thadeus Kiwanuka, Sarah Nakamanya, Richard Muhumuza, Winfred Nalukenge, Janet Seeley

O5 Exploring the acceptability of new biomedical HIV prevention technologies among MSM, adolescents and heterosexual adults in South Africa

Millicent Atujuna, Melissa Wallace, Ben Brown, Linda Gail Bekker, Peter A. Newman

O6 HIV-susceptible target cells in foreskins after voluntary medical male circumcision in South Africa

Rushil Harryparsad, Abraham J. Olivier, Heather B. Jaspan, Douglas Wilson, Janan Dietrich, Neil Martinson, Hillary Mukudu, Nonhlanhla Mkhize, Lynn Morris, Gianguido Cianci, Minh Dinh, Thomas Hope, Jo-Ann S. Passmore, Clive M. Gray

O7 HIV-1 proteins activate innate immune responses via TLR2 heterodimers

Bethany M. Henrick, Xiao-Dan Yao, Kenneth L. Rosenthal, the INFANT Study Team

O8 Characterization of an innate factor in human milk and mechanisms of action against HIV-1

Bethany M. Henrick, Xiao-Dan Yao, Anna G. Drannik, Alash’le Abimiku, Kenneth L. Rosenthal, the INFANT Study Team

O9 Secretor status and susceptibility to HIV infections among female sex workers in Nairobi, Kenya

Nadia Chanzu, Walter Mwanda, Julius Oyugi, Omu Anzala

O10 Natural Killer cell recall responsiveness to Gag-HIV-1 peptides of HIV-1 exposed but uninfected subjects are associated with peripheral CXCR6+ NK cell subsets

Moustapha Mbow, Sabelle Jallow, Moussa Thiam, Alberta Davis, Assane Diouf, Cheikh T. Ndour, Moussa Seydi, Tandakha N. Dieye, Souleymane Mboup, Martin Goodier, Eleanor Rilley, Assan Jaye

O11 Profiles of resistance: Local innate mucosal immunity to HIV-1 in commercial sex workers

Xiao-Dan Yao, RW. Omange, Bethany M. Henrick, Richard T. Lester, Joshua Kimani, T. Blake Ball, Francis A. Plummer, Kenneth L. Rosenthal

O12 Early antiretroviral therapy and pre-exposure prophylaxis for HIV prevention among female sex workers in Cotonou, Benin: A demonstration project

Luc Béhanzin, Fernand A. Guédou, Nassirou Geraldo, Ella Goma Mastétsé, Jerôme Charles Sossa, Marcel Djimon Zannou, Michel Alary

O13 Building capacity for HIV prevention trials: Preliminary data from a Nigerian cohort of HIV exposed sero-negatives (HESN)

Sophia Osawe, Evaezi Okpokoro, Felicia Okolo, Stephen Umaru, Rebecca Abimiku, Sam Audu, Pam Datong, Alash’le Abimiku

O14 Equipping healthcare professionals with skills required for the conduct of clinical trials in an effort to build capacity. Lessons learned

Jacquelyn Nyange, Joyce Olenja, Gaudensia Mutua, Walter Jaoko, Gloria Omosa-Manyonyi, Bashir Farah, Maureen Khaniri, Omu Anzala

O15 Educational technology to support active learning for HIV researchers and planners

Anne Cockcroft, Kendra Tonkin, Indu Girish, Puna Mhati, Ashley Cunningham, Neil Andersson

O16 From Lake Kivu (Rwanda) and Lake Malawi (Tanzania) to the shores of Lake Victoria (Uganda): Strengthening laboratory capacity through Good Clinical Laboratory Practice training

Bashir Farah, Jackton Indangasi, Walter Jaoko, Gaudensia Mutua, Maureen Khaniri, Jacquelyn Nyange, Omu Anzala

O17 Rilpivirine and etravirine resistance mutations in HIV-1 subtype C infected patients on a non-nucleoside reverse transcriptase inhibitor-based combination antiretroviral therapy in Botswana

Thabo Diphoko, Simani Gaseitsiwe, Victoria Maiswe, Thato Iketleng, Dorcas Maruapula, Keabetswe Bedi, Sikhulile Moyo, Rosemary Musonda, Mark Wainberg, Joseph Makhema, Vladimir Novitsky, Richard Marlink, Max Essex

O18 From home-based HIV testing to initiation of treatment: The AIDS Support Organization (TASO) Experience with Home-based HIV Counselling and Testing (HBHCT) among Adolescents in Uganda, 2005-2011

Stephen Okoboi, Livingstone Ssali, Sam Kalibala, Josephine Birungi, Aggrey Egessa, Jonathan Wangisi, Lyavala Joanne Okullu, Celestin Bakanda, Francis Obare⁴¹

O19 Feasibility study on using real time medication monitoring among HIV infected and Tuberculosis patients in Kilimanjaro, Tanzania

I. Marion Sumari-de Boer, Hadija H. Semvua, Jossy van den Boogaard, Krisanta W. Kiwango, Kennedy M. Ngowi, Pythia T. Nieuwkerk, Rob E. Aarnoutse, Ireen Kiwelu, Eva Muro, Gibson S. Kibiki

O20 Deaths still among sero-discordant cohort in Nigeria despite Access to treatment

Ruth Datiri, Grace Choji, Sophia Osawe, Evaezi Okpokoro, Felicia Okolo, Stephen Umaru, Rebecca Abimiku, Samuel Audu, Pam Datong, Alash’le Abimiku

O21 Therapeutic HIV-1 vaccine trials in Denmark and Guinea-Bissau

Fomsgaard A, Karlsson I, Jensen KJ, Jensen SS, Leo-Hansen C, Jespersen S, Da Silva Té D, Rodrigues CM, da Silva ZJ, Janitzek CM, Gerstoft J, Kronborg G, the WAPHIR Group

O22 Willingness to participate in a HIV vaccine Trial among HIV exposed sero-negative (HESN) persons in Jos, Nigeria

Evaezi Okpokoro, Sophia Osawe, Ruth Daitiri, Grace Choji, Stephen Umaru, Felicia Okolo, Pam Datong, Alash'le Abimiku

O23 Clinical research volunteers’ perceptions and experiences of screening for enrolment at KAVI-Institute of Clinical Research, Kenya

Nyariki Emily, Olenja Joyce, Lorway R. Robert, Anzala Anzala

O24 Gut microbiome, HIV-exposure, and vaccine responses in South African infants

Katie Viljoen, Jerome Wendoh, Elvis Kidzeru, Ulas Karaoz, Eoin Brodie, Gerrit Botha, Nicola Mulder, Clive Gray, William Cameron, Alain Stintzi, Heather Jaspan, for the INFANT study team

O25 Analysis of HIV pol diversity in the concentrated HIV epidemic in Saskatchewan

Paul N. Levett, David Alexander, Naveed Gulzar, Prabvir S. Grewal, Art F. Y. Poon, Zabrina Brumme, P. Richard Harrigan, James I. Brooks, Paul A. Sandstrom, Stryker Calvez, Stephen E. Sanche, Jamie K. Scott

P1 Evaluating a HIV vaccine research community engagement programme at two HIV prevention research centres in the Western Cape

Leslie Swartz, Ashraf Kagee, Anthea Lesch, Zuhayr Kafaar, Anneliese De Wet

P2 Validating HIV acquisition risk score using a cohort HIV exposed sero-negative persons in a discordant relationship in Jos, Nigeria, West Africa

Evaezi Okpokoro, Sophia Osawe, Ruth Daitiri, Grace Choji, Stephen Umaru, Felicia Okolo, Pam Datong, Alash'le Abimiku

P3 Bridging the gap between adults and adolescents and youth adults (AYA) – Employing a youth-centred approach to investigate HIV risk among AYA in Soweto and Durban, South Africa

Janan Dietrich, Tricia Smith, Laura Cotton, Stefanie Hornschuh, Martin van der Watt, Cari L. Miller, Glenda Gray, Jenni Smit, Manjeetha Jaggernath, Thumbi Ndung’u, Mark Brockman, Angela Kaida, on behalf of the AYAZAZI study teams

P4 Neighbours to sex workers: A key population that has been ignored

Maureen Akolo, Joshua Kimani, Prof Larry Gelmon, Michael Chitwa, Justus Osero

P5 Young women’s access to structural support programmes in a district of Botswana

Anne Cockcroft, Nobantu Marokoane, Leagajang Kgakole, Boikhutso Maswabi, Neo Mpofu, Umaira Ansari, Neil Andersson

P6 Voices for action from peri-urban Ugandan students, teachers and parents on HIV/STI prevention: Qualitative research results

Nakinobe Elizabeth, Miiro George Mukalazi, Zalwango Flavia, Nakiyingi-Miiro Jessica, Kaleebu Potiano

P7 Engaging Social Media as an education tool on the fly: The use of Facebook for HIV and Ebola prevention and awareness amongst adolescents in Uganda

John Ross Semwanga, Emily Nyanzi, Saidat Namuli Musoke, Elizabeth Nakinobe, George Miiro, Edward Katongole Mbidde, Tom Lutalo, Pontiano Kaleebu

P8 Circulating HIV-1 subtypes among sexual minority populations in Zambia

Ray Handema, Graham P. Chianzu

P9 The Development of HIV Bio-bank resource management to support clinical trial and Intervention research: WAPHIR experience

Moussa Thiam, Diabou Diagne-Gueye, Mame K. Ndiaye, Moustapha Mbow, Birahim P. Ndiaye, Ibrahima Traore, Mamadou C. Dia, Gilleh Thomas, Coumba Tour-Kane, Souleymane Mboup, Assan Jaye

P10 Capacity building for clinical trials as a novel approach for scaling up HIV prevention research initiatives in East Africa: achievements and challenges

Emily Nyanzi, Edward Katongole Mbidde, Pontiano Kaleebu, Juliet Mpendo, Joshua Kimani, Josephine Birungi, Winnie Muyindike, Andrew Kambugu

P11 Community and media perspective of research; an advocacy workshop on HIV prevention research

Hachizovu Sebastian, Handema Ray, Chaponda Mike, Kabuya Jean Bertin, Mulenga Modest

P12 Development of a quantitative HIV-1 and HIV-2 real time PCR (qRT-PCR) viral load assay

Moussa Thiam, Omar Janha, Alberta Davis, Alfred Amambua-Ngwa, Davis C. Nwakanma, Souleymane Mboup, Assan Jaye

P13 Differential effects of sex in a West African Cohort of HIV-1, HIV-2 and HIV-1/2 dual infected patients: Men are worse off

Sanne Jespersen, Bo Langhoff Hønge, Joakim Esbjörnsson, Candida Medina, David Da Silva TÉ, Faustino Gomes Correira, Alex Lund Laursen, Lars Østergaard, Andreas Andersen, Peter Aaby, Christian Erikstrup, Christian Wejse, for the Bissau HIV Cohort study group

P14 HIV-infected adolescents in transition from pediatric to adult HIV care in Dakar, Senegal: sample characteristics and immunological and virological profiles

Siry Dieye, Moussa Sarr, Haby Sy, Helene D Mbodj, Marianne Ndiaye, Amy Ndiaye, Seydi Moussa, Assan Jaye, Souleymane Mboup¹⁰⁰

P15 Molecular characterization of vertically transmitted HIV-1 among children born to HIV-1 seropositive mothers in Northern Tanzania

Balthazar M. Nyombi, Elichilia R. Shao, Innocent B. Chilumba, Sikhulile Moyo, Simani Gaseitsiwe, Rosemary Musonda

P16 Breast-fed HIV-1 exposed infants play catch up. A preliminary report

Pam Datong, Bucky Inyang, Sophia Osawe, Abel Izang, Chundung Cole, Felicia Okolo, Bill Cameron, Kenneth Rosenthal, Clive Gray, Heather Jaspan, Alash’le Abimiku, the INFANT study team

P17 The frequency of N348I mutation in patient failing combination antiretroviral treatment In Botswana

Boitumelo Seraise, Kerstin Andrea-Marobela, Sikhulile Moyo, Rosemary Musonda, Joseph Makhema, Max Essex, Simani Gaseitsiwe

Does HIV Exploit the Inflammatory Milieu of the Male Genital Tract for Successful Infection?

In many parts of the World, medical male circumcision (MMC) is used as standard prevention of care against HIV infection. This is based on seminal reports made over 10 years ago that removal of the foreskin provides up to 60% protection against HIV infection in males and seems currently the best antiretroviral-free prevention strategy yet against the global epidemic. We explore the potential mechanisms by which MMC protects against HIV-1 acquisition and that one of the oldest, albeit re-invented, rituals of removing a foreskin underscores the exploitative nature of HIV on the anatomy and tissue of the uncircumcised penis. Furthermore, foreskin removal also reveals how males acquire HIV, and in reality, the underlying mechanisms of MMC are not known. We argue that the normal sequelae of inflammation in the male genital tract (MGT) for protection from sexually transmitted infections (STI)-induced pathology represents a perfect immune and microbial ecosystem for HIV acquisition. The accumulation of HIV-1 target cells in foreskin tissue and within the urethra in response to STIs, both during and after resolution of infection, suggests that acquisition of HIV-1, through sexual contact, makes use of the natural immune milieu of the MGT. Understanding immunity in the MGT, the movement of HIV-1 target cells to the urethra and foreskin tissue upon encounter with microbial signals would provide more insight into viral acquisition and lay the foundation for further prevention strategies in males that would be critical to curb the epidemic in all sexual partners at risk of infection. The global female-centric focus of HIV-1 transmission and acquisition research has tended to leave gaps in our knowledge of what determines HIV-1 acquisition in men and such understanding would provide a more balanced and complete view of viral acquisition.

Delayed BCG immunization does not alter antibody responses to EPI vaccines in HIV-exposed and -unexposed South African infants

BACKGROUND

Bacille Calmette-Guérin (BCG) is routinely given at birth in tuberculosis-endemic settings due to its protective effect against disseminated tuberculosis in infants. BCG is however contraindicated in HIV-infected infants. We investigated whether delaying BCG vaccination to 14 weeks of age affected vaccine-induced antibody responses to Haemophilus influenzae type b (Hib)-conjugate, pertussis, tetanus and Hepatitis B (HBV) vaccines, in HIV-exposed uninfected (HEU) and -unexposed uninfected (HUU) infants.

METHODS

Infants were randomized to receive BCG at birth or at 14 weeks of age. Blood was taken at 14, 24, and 52 weeks of age and analyzed for Hib, pertussis, tetanus and HBV specific antibodies.

RESULTS

BCG was given either at birth (106 infants, 51 HEU) or at 14 weeks of age (74 infants, 50 HEU). The timing of BCG vaccination did not influence the antibody response to any antigen studied. However, in a non-randomized comparison, HEU infants had higher Hib antibody concentrations at weeks 14 and 24 (p=0.001 and <0.001, respectively) and pertussis at week 24 (p=0.003). Conversely, HEU infants had lower antibody concentrations to HBV at 14 and 52 weeks (p=0.032 and p=0.031) with no differences in tetanus titres.

CONCLUSIONS

HIV exposure, but not the timing of BCG vaccination, was associated with antibody concentrations to Hib, pertussis, HBV and tetanus primary immunization.

CLINICAL TRIAL REGISTRATION

DOH-27-1106-1520.

Relationship between female genital tract infections, mucosal interleukin-17 production and local T helper type 17 cells

T helper type 17 (Th17) cells play an important role in immunity to fungal and bacterial pathogens, although their role in the female genital tract, where exposure to these pathogens is common, is not well understood. We investigated the relationship between female genital tract infections, cervicovaginal interleukin-17 (IL-17) concentrations and Th17 cell frequencies. Forty-two cytokines were measured in cervicovaginal lavages from HIV-uninfected and HIV-infected women. Frequencies of Th17 cells (CD3(+) CD4(+) IL-17a(+)) were evaluated in cervical cytobrushes and blood by flow cytometry. Women were screened for Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma genitalium, Trichomonas vaginalis and herpes simplex virus 2 by PCR, and candidal infections and bacterial vaginosis by Gram stain. Women with bacterial sexually transmitted infections (STIs), specifically chlamydia and gonorrhoea, had higher genital IL-17 concentrations than women with no STI, whereas women with candidal pseudohyphae/spores had lower IL-17 concentrations compared with women without candidal infections. Viral STIs (herpes simplex virus 2 and HIV) were not associated with significant changes in genital IL-17 concentrations. Genital IL-17 concentrations correlated strongly with other inflammatory cytokines and growth factors. Although Th17 cells were depleted from blood during HIV infection, cervical Th17 cell frequencies were similar in HIV-uninfected and HIV-infected women. Cervical Th17 cell frequencies were also not associated with STIs or candida, although few women had a STI. These findings suggest that IL-17 production in the female genital tract is induced in response to bacterial but not viral STIs. Decreased IL-17 associated with candidal infections suggests that candida may actively suppress IL-17 production or women with dampened IL-17 responses may be more susceptible to candidal outgrowth.

Delayed BCG vaccination results in minimal alterations in T cell immunogenicity of acellular pertussis and tetanus immunizations in HIV-exposed infants

BACKGROUND

Bacille Calmette-Guerin (BCG) is effective in preventing disseminated tuberculosis (TB) in children but may also have non-specific benefits, and is thought to improve immunity to unrelated antigens through trained innate immunity. In HIV-infected infants, there is a risk of BCG-associated adverse events. We aimed to explore whether delaying BCG vaccination by 8 weeks, in utero or perinatal HIV infection is excluded, affected T-cell responses to B. pertussis (BP) and tetanus toxoid (TT), in HIV-exposed, uninfected infants.

METHODS

Infants were randomized to receive BCG vaccination at birth or 8 weeks of age. At 8 and 14 weeks, T cell proliferation and intracellular cytokine (IL-2, IL-13, IL-17, and IFN-γ) expression was analyzed in response to BP, TT and Staphylococcal enterotoxin B (SEB) antigens.

RESULTS

Delaying BCG vaccination did not alter T-cell proliferation to BP or TT antigens. Infants immunized with BCG at birth had higher CD4+ T cell proliferation to SEB at 14 weeks of age (p=0.018). Birth-vaccinated infants had increased CD8+ IL-2 expression in response to BP, but not TT or SEB, at 8 weeks. Infants vaccinated with BCG at 8 weeks had significantly lower IL-13 expression by BP-specific CD4+ and CD8+ T cells at 14 weeks (p=0.032 and p=0.0035, respectively). There were no observed differences in multifunctional cytokine response to TT, BP or SEB between infants vaccinated with BCG at birth versus 8 weeks of age.

CONCLUSION

Delaying BCG vaccination until 8 weeks of age results in robust T-cellular responses to BP and TT in HIV-exposed infants.

CLINICAL TRIAL REGISTRY

NCT02062580.

Immunogenicity of BCG in HIV-exposed and non-exposed infants following routine birth or delayed vaccination

BACKGROUND

Human immunodeficiency virus (HIV) exposed infants are at high risk of Mycobacterium tuberculosis exposure, have high rates of progression to tuberculosis (TB) disease and are at significant risk of bacille Calmette-Guérin (BCG) induced adverse events.

OBJECTIVE

To evaluate a delayed BCG vaccination strategy in HIV-exposed infants.

DESIGN

A randomised trial of routine BCG vaccination given at birth compared to 14 weeks of age in HIV-exposed non-infected and non-HIV-exposed infants to investigate longitudinal BCG-induced immune responses using a 7-day whole blood interferon-gamma (IFN-γ) enzyme-linked immunosorbent assay.

RESULTS

A significantly higher proportion of infants had positive responses to M. tuberculosis purified protein derivative (PPD) and BCG at 14 weeks in the birth vs. delayed vaccination groups (P = 0.001 for both). This difference was no longer apparent at weeks 24 or 52. Among infants vaccinated at birth, the 14-week IFN-γ response to M. tuberculosis PPD was lower among HIV-exposed than non-exposed infants (276.5 pg/ml vs. 790.2, P = 0.048). Among all infants, there were significant correlations between the magnitude of IFN-γ responses to BCG, M. tuberculosis PPD, TB 10.4 and culture filtrate protein 10/early secreted antigenic target 6.

CONCLUSIONS

The timing of vaccination had limited effect on BCG-induced IFN-γ responses, which waned considerably over 1 year despite initial vigorous responses in both vaccination groups. The lower responses in HIV-exposed non-infected infants suggest potentially altered mycobacterial immunity early in life.

Delaying BCG vaccination until 8 weeks of age results in robust BCG-specific T-cell responses in HIV-exposed infants

BACKGROUND

BCG vaccination prevents disseminated tuberculosis in children, but it is contraindicated for persons with human immunodeficiency virus (HIV) infection because it can result in severe disease in this population. In tuberculosis-endemic regions, BCG vaccine is administered soon after birth, before in utero and peripartum HIV infection is excluded. We therefore assessed the immunogenicity of BCG vaccine in HIV-exposed infants who received BCG at birth or at 8 weeks of age.

METHODS

HIV-exposed, uninfected infants were randomly assigned to receive BCG vaccination at birth (the early vaccination arm) or 8 weeks of age (the delayed vaccination arm). BCG-specific proliferative and intracellular cytokine responses were assessed in 28 infants per arm at 6, 8, and 14 weeks of life.

RESULTS

There was no difference in BCG-specific T-cell proliferation between the study arms 6 weeks after vaccination. However, at 14 weeks of age, the frequency of interferon γ-expressing CD4(+) T cells and multifunctional BCG-specific responses in the delayed vaccinated arm were significantly higher than those in the early vaccination arm (P = .021 and P = .011, respectively).

CONCLUSIONS

The immunogenicity of BCG vaccination in HIV-exposed, uninfected infants is not compromised when delayed until 8 weeks of age and results in robust BCG-specific T-cell responses at 14 weeks of age. These findings support further evaluation of this modified BCG vaccination strategy for HIV-exposed infants.

CLINICAL TRIALS REGISTRATION

NCT02062580.

In-utero exposure to maternal HIV infection alters T-cell immune responses to vaccination in HIV-uninfected infants

OBJECTIVE

In sub-Saharan Africa, HIV-exposed uninfected (HEU) infants have higher morbidity and mortality than HIV-unexposed infants. To evaluate whether immune dysfunction contributes to this vulnerability of HEU infants, we conducted a longitudinal, observational cohort study to assess T-cell immune responses to infant vaccines (Mycobacterium bovis BCG and acellular pertussis) and staphylococcal enterotoxin B (SEB). In total, 46 HEU and 46 HIV-unexposed infants were recruited from Khayelitsha, Cape Town.

METHODS

Vaccine-specific T-cell proliferation (Ki67 expression) and intracellular expression of four cytokines [interferon-γ, interleukin (IL)-2, IL-13 and IL-17] were measured after whole blood stimulation with antigens at 6 and 14 weeks of age.

RESULTS

HEU infants demonstrated elevated BCG-specific CD4 and CD8 T-cell proliferative responses at 14 weeks (P  = 0.041 and 0.002, respectively). These responses were significantly increased even after adjusting for birth weight, feeding mode and gestational age. Similar to BCG, increased CD4 and CD8 T-cell proliferation was evident in response to SEB stimulation (P  = 0.004 and 0.002, respectively), although pertussis-specific T cells proliferated comparably between the two groups. Within HEU infants, maternal CD4 cell count and length of antenatal antiretroviral exposure had no effect on T-cell proliferation to BCG or SEB. HIV exposure significantly diminished measurable cytokine polyfunctionality in response to BCG, Bordetella pertussis and SEB stimulation.

CONCLUSION

These data show for the first time, when adjusting for confounders, that exposure to HIV in utero is associated with significant alterations to CD4 and CD8T-cell immune responses in infants to vaccines and nonspecific antigens.

Role of semen in altering the balance between inflammation and tolerance in the female genital tract: does it contribute to HIV risk?

While the main reproduction aim of semen is the transport of spermatozoa to the female genital tract, seminal plasma is a complex fluid that also carries a broad array of immunologically active molecules. Seminal plasma has been shown to contain a diverse array of anti-inflammatory and pro-inflammatory soluble mediators that regulate immune responses within the female reproductive tract than can facilitate fertilization. Since the natural inflammatory response to semen deposition in the female genital tract may result in recruitment of activated HIV target cells into the female genital mucosa, we discuss the constituents of semen that may increase the risk for HIV infection in women.

The oral mucosa immune environment and oral transmission of HIV/SIV

The global spread of human immunodeficiency virus (HIV) is dependent on the ability of this virus to efficiently cross from one host to the next by traversing a mucosal membrane. Unraveling how mucosal exposure of HIV results in systemic infection is critical for the development of effective therapeutic strategies. This review focuses on understanding the immune events associated with the oral route of transmission (via breastfeeding or sexual oral intercourse), which occurs across the oral and/or gastrointestinal mucosa. Studies in both humans and simian immunodeficiency virus (SIV) monkey models have identified viral changes and immune events associated with oral HIV/SIV exposure. This review covers our current knowledge of HIV oral transmission in both infants and adults, the use of SIV models in understanding early immune events, oral immune factors that modulate HIV/SIV susceptibility (including mucosal inflammation), and interventions that may impact oral HIV transmission rates. Understanding the factors that influence oral HIV transmission will provide the foundation for developing immune therapeutic and vaccine strategies that can protect both infants and adults from oral HIV transmission.

Utility of clinical parameters to identify HIV infection in infants below ten weeks of age in South Africa: a prospective cohort study

BACKGROUND

As HIV-infected infants have high mortality, the World Health Organization now recommends initiating antiretroviral therapy as early as possible in the first year of life. However, in many settings, laboratory diagnosis of HIV in infants is not readily available. We aimed to develop a clinical algorithm for HIV presumptive diagnosis in infants < 10 weeks old using screening data from the Children with HIV Early Antiretroviral therapy (CHER) study in South Africa.HIV-infected and HIV-uninfected exposed infants < 10 weeks of age were identified through Vertical Transmission Prevention programs. Clinical and laboratory data were systematically recorded, groups were compared using Kruskal-Wallis, analysis of variance (ANOVA), and Fisher's exact tests. Receiver Operating Characteristic (ROC) curves were compiled using combinations of clinical findings.

RESULTS

417 HIV-infected and 125 HIV-exposed, uninfected infants, median age 46 days (IQR 38-55), were included. The median CD4 percentage in HIV-infected infants was 34 (IQR 28-41)%. HIV-infected infants had lower weight-for-age, more lymphadenopathy, oral thrush, and hepatomegaly than exposed uninfected infants (Adjusted Odds Ratio 0.51, 8.8, 5.6 and 23.5 respectively; p < 0.001 for all). Sensitivity of individual signs was low (< 20%) but specificity high (98-100%). If any one of oral thrush, hepatomegaly, splenomegaly, lymphadenopathy, diaper dermatitis, weight < 50(th) centile are present, sensitivity for HIV infection amongst HIV-exposed infants was 86%. These algorithms performed similarly when used to predict severe immune suppression.

CONCLUSIONS

A combination of physical findings is helpful in identifying infants most likely to be HIV-infected. This may inform management algorithms and provide guidance for focused laboratory testing in some settings, and should be further validated in these settings and elsewhere.

Intra- and inter-clade cross-reactivity by HIV-1 Gag specific T-cells reveals exclusive and commonly targeted regions: implications for current vaccine trials

The genetic diversity of HIV-1 across the globe is a major challenge for developing an HIV vaccine. To facilitate immunogen design, it is important to characterize clusters of commonly targeted T-cell epitopes across different HIV clades. To address this, we examined 39 HIV-1 clade C infected individuals for IFN-γ Gag-specific T-cell responses using five sets of overlapping peptides, two sets matching clade C vaccine candidates derived from strains from South Africa and China, and three peptide sets corresponding to consensus clades A, B, and D sequences. The magnitude and breadth of T-cell responses against the two clade C peptide sets did not differ, however clade C peptides were preferentially recognized compared to the other peptide sets. A total of 84 peptides were recognized, of which 19 were exclusively from clade C, 8 exclusively from clade B, one peptide each from A and D and 17 were commonly recognized by clade A, B, C and D. The entropy of the exclusively recognized peptides was significantly higher than that of commonly recognized peptides (p = 0.0128) and the median peptide processing scores were significantly higher for the peptide variants recognized versus those not recognized (p = 0.0001). Consistent with these results, the predicted Major Histocompatibility Complex Class I IC₅₀ values were significantly lower for the recognized peptide variants compared to those not recognized in the ELISPOT assay (p<0.0001), suggesting that peptide variation between clades, resulting in lack of cross-clade recognition, has been shaped by host immune selection pressure. Overall, our study shows that clade C infected individuals recognize clade C peptides with greater frequency and higher magnitude than other clades, and that a selection of highly conserved epitope regions within Gag are commonly recognized and give rise to cross-clade reactivities.

Effect of caregivers' depression and alcohol use on child antiretroviral adherence in South Africa

Pediatric antiretroviral adherence is difficult to assess, and subjective measures are affected by reporting bias, which in turn may depend on psychosocial factors such as alcohol use and depression. We enrolled 56 child-caregiver dyads from Cape Town, South Africa and followed their adherence over 1 month via various methods. The Alcohol Use Disorder Inventory Tool and Beck Depression Inventory 1 were used to assess these factors and their affect on pediatric adherence. The median age of the children was 4 years, and median time on antiretrovirals was 20 months. Increased time on ART was associated with poorer adherence via 3-day recall (3DR; p=0.03). Ethanol use was inversely associated with adherence by both subjective measures, 3DR and visual analogue scale (VAS) (both p<0.01), and with Medication Event Monitoring System (MEMS) adherence as a continuous variable. In a multivariate analysis predicting MEMS adherence greater than 95%, including variables that were associated with adherence in univariate analyses, having a mother as a caregiver and shorter time on highly active antiretroviral therapy (HAART) were significantly associated with adherence (odds ratio [OR] 19.2; 95% confidence interval [CI] 1.1-327 and 0.9; 95% CI 0.9-0.99). Pediatric adherence is affected by caregiver alcohol use, but caregiver relationship to the child is most important. This small study suggests that interventions should aim to keep mothers healthy and alive, as well as alcohol-free.

Immune activation in the female genital tract during HIV infection predicts mucosal CD4 depletion and HIV shedding

Plasma viral load predicts genital tract human immunodeficiency virus (HIV) shedding in HIV-infected women. We investigated whether local mucosal T-cell activation (HLA-DR, CD38, CCR5, and Ki67) contributed to HIV shedding in the genital tracts of HIV-infected women. We showed that cervical cytobrush-derived T cells expressed higher frequencies of T-cell activation markers (CD38+ and HLA-DR+) than blood-derived T cells. Expression was significantly higher in HIV-infected women than in uninfected women. We found that the frequency of activated proliferating cervical T cells (Ki67+; Ki67+CCR5+) broadly predicted HIV shedding in the genital tract in HIV-infected women, independently of plasma viral loads. Furthermore, activated cervical T cells (HLA-DR+CD38+ and HLA-DR+CCR5+) and local HIV shedding were independently associated with CD4 depletion in the genital tract. These data suggest that the presence of high frequencies of activated T cells in the female genital mucosa during HIV infection facilitates both local HIV shedding and CD4 T-cell depletion.

Sexual health, HIV risk, and retention in an adolescent HIV-prevention trial preparatory cohort

PURPOSE

Although adolescents are at high risk for human immunodeficiency virus (HIV) infection, they have not been, included in HIV vaccine trials.

METHODS

In preparation for enrollment in HIV vaccine trials, 100 HIV-negative adolescents aged 14-17 years from Cape Town were recruited into a cohort. HIV, syphilis, pregnancy testing, and sexual risk questionnaires were conducted at varying intervals for a year.

RESULTS

The mean age of the participants was 15 years, and 70% of them were female. Recruitment was completed within 3 months. Retention was found to be 82% at 1-year follow-up. The main reasons for dropout were as follows: relocation to other communities, phlebotomy, and visit frequency. In a Cox proportional hazards model, only female gender was significantly associated with retention. No change in reported sexual risk occurred, but the proportion of individuals who were aware of their partner's HIV status was significantly higher (17% at baseline, 83% at 1-year follow-up; p < .001). Five pregnancies were reported during follow-up.

CONCLUSIONS

To our knowledge, this is the first prospective adolescent HIV-prevention cohort in Southern Africa. Despite reports of risky sexual behaviors and high pregnancy rates, HIV seroconversions did not occur in the retained cohort. HIV-prevention trials with high-risk adolescents will require rigorous efforts to prevent future pregnancies, and may require risk eligibility criteria. Retention may improve with transport provision, visits with incentives, and efforts to retain males.

Standard measures are inadequate to monitor pediatric adherence in a resource-limited setting

This study aims to compare the use and cost of objective and subjective measures of adherence to pediatric antiretroviral treatment in a primary care facility in South Africa. In a 1-month longitudinal study of 53 caregiver-child dyads, pharmacy refill (PR), measurement of returned syrups (RS), caregiver self-report (3DR) and Visual Analogue Scale (VAS) were compared to Medication Event Monitoring System (MEMS). Adherence was 100% for both VAS and 3DR; by PR and RS 100% and 103%, respectively. MEMS showed that 92% of prescribed doses were administered, but only 66% of these within the correct 12-hourly interval. None of the four measures correlated significantly with MEMS. MEMS data suggest that timing of doses is often more deviant from prescribed than expected and should be better addressed when monitoring adherence. Of all, MEMS was by far the most expensive measure. Alternative, cheaper electronic devices need to be more accessible in resource-limited settings.

A qualitative assessment of perspectives on the inclusion of adolescents in HIV vaccine trials in South Africa

Adolescents are at high risk for HIV acquisition, and thus need to be included in HIV vaccine trials. In preparation for inclusion of adolescents in HIV vaccine trials in an urban community in Cape Town with a high antenatal HIV prevalence, the study assessed the attitudes towards the inclusion of adolescents in HIV vaccine trials. A total of 18 focus group discussions were conducted using a semistructured interview guide. The participants (n = 200) were adolescents, young adults, parents and other key informants. Participants from all groups welcomed the inclusion of adolescents in HIV vaccine trials due to their high-risk status. There were, however, concerns about sexual disinhibition, fear of side-effects, fear of HIV testing and disclosure of HIV status, mistrust of nurses and clinics. The study highlighted a number of ethical and social issues that need to be addressed before the trials.

Multidrug-resistant Enterococcus faecium meningitis in a toddler: characterization of the organism and successful treatment with intraventricular daptomycin and intravenous tigecycline

A case of enterococcal meningitis in a toddler is presented. The organism was highly resistant to all drugs previously used for pediatric Gram-positive meningitis. She was successfully treated with intraventricular and intravenous daptomycin and intravenous tigecycline. The organism was characterized as a member of CC17, a notorious emerging nosocomial clone of Enterococcus faecium.

The emerging need for adolescent-focused HIV care in South Africa

No Abstract

The role of polyclonal intravenous immunoglobulin in treating HIV-infected children with severe bacterial infections: a retrospective cohort study

Background

Mortality among HIV-infected children in developing countries remains high after serious bacterial infections despite the use of antibiotics. Intravenous immunoglobulin (IVIG) has been used as an adjuvant therapy to treat these infections, but little data exists regarding its efficacy, and previous studies have focused on IVIG as a prophylactic agent. We examined the impact of IVIG as an adjuvant therapy in reducing mortality and length of hospital stay in HIV-infected children with serious bacterial infections.

Methods

This retrospective study focused on pediatric admissions at a large urban hospital between 2002 and 2006. Children between the ages of one month and nine years of age with laboratory confirmed HIV-status, serious bacterial infection, no prior exposure to IVIG, and a hospital length of stay of 5 days or more, were eligible for inclusion.

Results

A total of 140 children (median age 1.2 years) met inclusion criteria; lower respiratory tract infection was diagnosed in 94 (67%) of the children, while 74 (53%) had bacterial sepsis. Fifty-four (39%) children were receiving antiretroviral therapy and 39 (28%) were receiving tuberculosis treatment. Overall 73 (52%) were treated with IVIG, with the majority (74%) of children receiving a single dose. Thirteen (9%) died during their hospital admission. In crude analysis IVIG was significantly associated with increased mortality was (Odds Ratio (OR): 5.8; 95% Confidence Interval (CI): 1.2–27.1) and this association was weakened by adjustment for other predictors of mortality (OR 4.3, 95% CI 0.7–27.9, p = 0.123). IVIG use was also associated with longer hospital stays.

Conclusion

Administration of one to three doses of IVIG during the acute phase of illness does not appear to reduce mortality or the length of hospital stays in HIV-infected children with serious bacterial infections. However, the retrospective nature of this study makes confounding by indication difficult to control and further studies regarding the timing, dosing, and method of administration are required. Nonetheless the routine use of IVIG in resource-limited settings should be carefully considered given its high cost.

Bacterial disease and antimicrobial susceptibility patterns in HIV-infected, hospitalized children: a retrospective cohort study

Background

Serious bacterial infections are a major source of morbidity and mortality in HIV-infected children. The spectrum of disease is wide, and responsible organisms vary according to setting. The use of antibiotic prophylaxis and the emergence of multi-drug resistant bacteria necessitate examination of responsible organisms and their antibiotic susceptibility.

Methodology/Principal Findings

A retrospective cohort study of all HIV-positive pediatric admissions at an urban public sector hospital in Cape Town between January 2002 and June 2006 was conducted. Children between the ages of one month and nine years with laboratory confirmed HIV status, serious bacterial infection, and a hospital length of stay of 5 days or more, were eligible for inclusion. Organisms isolated from blood, urine, and cerebral spinal fluid cultures and their antimicrobial susceptibility were examined, and compared according to timing of isolation to distinguish nosocomial versus community-acquired. One hundred and forty-one children were identified (median age 1.2 years), 39% of whom were on antiretrovirals started before or during this hospitalization. Bacterial infections involved all organ systems, however pneumonia was most common (67%). S. pneumoniae and S. aureus were the most common gram positive and K. pneumoniae was the most common gram negative organism. K pneumoniae isolates were resistant to many first and second line antibiotics, and were all considered nosocomial. All S. aureus isolates were methicillin resistant, some of which were community-acquired.

Conclusions/Significance

Bacterial infections are an important source of co-morbidity in HIV-infected children in resource-limited settings. Clinicians should have a low threshold to initiate antibiotics in children requiring hospitalization. Broad-spectrum antibiotics should be used judiciously. Clinicians caring for HIV-infected children should be cognizant of the most common organisms affecting such children, and of their local antimicrobial susceptibilities, when treating empirically for serious bacterial infections.

Community perspectives on the ethical issues surrounding adolescent HIV vaccine trials in South Africa

Adolescents globally are at high risk for HIV acquisition and are the targets of HIV prevention interventions such as HIV vaccines. In order to understand stakeholders' attitudes towards the ethical issues of adolescent involvement in HIV vaccine trials, we conducted focus group discussions with key members of a semi-urban, informal Cape Town community with high HIV prevalence in which HIV vaccine trials are taking place. Themes were identified from focus group transcripts by four researchers, and included necessity of guardian consent, age of independent consent, and confidentiality of in-trial medical results. In general, ethical adolescent HIV vaccine trials will be feasible in this community.

Brief report: Methods for collecting sexual behaviour information from South African adolescents—a comparison of paper versus personal digital assistant questionnaires

Reporting bias in adolescent behavioural research may be overcome with the use of personal digital assistants (PDA) or other computer based technologies. However, there is little insight into the use of these tools among adolescents in low resource settings. We compared self-administered paper questionnaires with PDA questionnaires to collect sexual behaviour data from a sample of 11-19 year olds living in a periurban, Xhosa-speaking community in South Africa. There was a high level of agreement between sexual risk behaviour data collected via each method (kappas> or = 0.50). Data collected from the PDA questionnaires were more complete. Subjectively, adolescents found the use of PDA to be simple and confidential. PDA may be a useful method to collect sensitive, self-reported information from adolescents in resource-limited settings.

Adolescent HIV prevalence, sexual risk, and willingness to participate in HIV vaccine trials

PURPOSE

To determine human immunodeficiency virus (HIV) prevalence, sexual risk behaviors, and attitudes toward HIV vaccine trials among 11-19 year-olds in a peri-urban community near Cape Town, South Africa.

METHODS

We performed HIV antibody testing on oral transudate, and assessed sexual risk behaviors and willingness to participate in HIV vaccine trials using self-administered questionnaires.

RESULTS

Of the 510 adolescents selected, 356 (73%) participated. The HIV prevalence of the group was 10.6% (95% confidence interval [CI] 7.5-14.4). One-third of adolescents had experienced sexual debut, with a mean age of 14.6 years. Number of lifetime sexual partners was independently associated with HIV infection (odds ratio [OR] = 1.62; 95% CI 1.1-2.3). In a multivariate analysis, increasing age, female gender, and attending school were independently associated with having had sex. The majority of adolescents (79%) were willing to participate in an HIV vaccine trial. Increasing age and length of residence in the community were significantly associated with willingness to participate (OR = 1.19; 95% CI 1.01-1.4 and OR = 1.14; 95% CI 1.03-1.26, respectively).

CONCLUSIONS

The prevalence of HIV and risk behavior among adolescents in this community is high. HIV vaccines are required that target preadolescents. HIV vaccine trials in adolescents in this setting will be facilitated by their willingness to participate.

Amniotic fluid has higher relative levels of lentivirus-specific antibodies than plasma and can contain neutralizing antibodies

BACKGROUND

The in utero transmission rate of HIV-1 is estimated to be 10-15% in the absence of interventions and breastfeeding. Natural protective mechanisms involving lentivirus-specific antibodies may therefore exist to limit in utero transmission of lentiviruses.

OBJECTIVES

HIV-1- and SIV-specific immunoglobulin G (IgG) levels in amniotic fluid samples from humans and rhesus macaques were assessed.

STUDY DESIGN

HIV-1- and SIV-specific immunoglobulin G levels, relative to total IgG concentrations in amniotic fluid samples from humans and rhesus macaques, were determined using a quantitative Western blotting procedure. Amniotic fluid from rhesus macaques was tested for the ability to neutralize SIV infection of CEMX174 cells.

RESULTS

The levels of HIV-1- and SIV-specific immunoglobulin G, relative to total IgG concentrations in amniotic fluid samples from humans and rhesus macaques, were approximately 3-10-fold higher than in plasma. The ability of antibodies in human amniotic fluid samples to neutralize viral infectivity could not be assessed, because zidovidine was present in the samples. Most amniotic fluid samples from rhesus macques not treated with antiretrovirals were able to neutralize SIV infectivity, except for a sample from a SIV positive rhesus whose infant was infected in utero.

CONCLUSIONS

Active immunity to HIV-1 resulting in virus-specific antibodies in amniotic fluid exists, and may be a natural barrier to in utero infection. This may provide hope for stimulating neutralizing antibody via vaccine design.

Preventing neonatal HIV: a review

Mother-to-child transmission of human immunodeficiency virus type 1 has become rare in developed countries, with the use of highly active antiretroviral treatment, elective cesarean section, and avoidance of breastfeeding. In the developing world, however, these interventions are unfeasible, and cost-saving methods for prevention of vertical transmission are vital. Prevention begins with voluntary counseling and testing, improved maternal education and access to prenatal care. Various antiretroviral drugs administered before, during, and for short periods after delivery have decreased vertical transmission. Where safe and compliant formula feeding is difficult, avoidance of mixed feeding may improve infant outcomes. However, post-natal transmission via breast milk remains a major challenge. As we continue to find cost-effective answers to protect infants worldwide, the search for a HIV-1 vaccine continues.

Quantitative competitive reverse transcription polymerase chain reaction is not a useful method for quantification of CD4 and CD8 cell status during HIV infection

BACKGROUND

A polymerase chain reaction (PCR)-based method for quantitating CD4 and CD8 mRNA could provide a means of assessing immune status of AIDS patients and other immunologically compromised persons without requiring large blood draws, and could be exquisitely sensitive. Such a method would also be useful in assessing the immune status of patients retrospectively.

RESULTS

Quantitative competitive reverse transcription PCR (QC-RT-PCR) assays were developed for measurement of CD4 and CD8 mRNA. Samples were obtained from HIV-positive and negative patients whose CD4 and CD8 counts had been determined via Flow Cytometry. The quantity of CD4 (n = 13) and CD8 (n = 28) mRNA standardized according to GAPDH mRNA quantities, all determined by QC-RT-PCR, were compared to cell number as determined by flow cytometry. There was no correlation between CD4 and CD8 cell counts and mRNA levels of CD4 and CD8 as determined by QC-RT-PCR. There is no correlation between CD4 and CD8 mRNA levels and the number of cells expressing these proteins on their surface.

CONCLUSION

QC-RT-PCR, and related methodologies are not useful substitutes for assessment of CD4 and CD8 cell numbers in HIV-infected persons.

Expression of granzyme B mRNA is altered in human immunodeficiency virus infected patients

CD8-positive cytotoxic T lymphocytes and natural killer cells are the major cytotoxic components of the antiviral immune response. The major pathway used by these cells in response to viral-infected cells involves granzymes, cytotoxic granule serine proteases involved in the pathway leading to target cell DNA fragmentation and apoptosis. The levels of granzyme B mRNA in peripheral blood cells of human immunodeficiency virus (HIV) type-1 infected patients in comparison to noninfected individuals were assessed by quantitative competitive reverse transcriptase polymerase chain reaction. Expression of granzyme B mRNA is altered in HIV-1 infected patients. Significantly fewer HIV patients had detectable granzyme B mRNA levels than controls. The one HIV-infected patient with detectable granzyme B mRNA displayed a much higher level of this mRNA than all healthy controls. Cell-mediated cytotoxicity during HIV-1 infection may be impaired due to a deficient quantity of active cytotoxic granules or to their abnormal regulation.