A Cross-sectional Study to Compare Hepatitis B Immunity in HIV-infected and HIV-uninfected Kenyan Children After Primary Hepatitis B Immunization.

To evaluate protective antibody levels against hepatitis B surface antigen in HIV-infected and HIV-uninfected Kenyan children, this study enrolled 531 children. In the HIV-infected group, only 18.3% had protective hepatitis B surface antigen compared with 74.4% in the HIV-uninfected group (P < 0.0001). Perhaps HIV-infected children should be immunized differently.

The Impact and Successes of a Paediatric Endocrinology Fellowship Program in Africa.

Background. The prevalence and distribution of endocrine disorders in children in Africa are not well known because most cases are often undiagnosed or diagnosed too late. The awareness of this led to the launch of the Paediatric Endocrinology Training Center for Africa (PETCA) designed to improve quality and access to health care by training paediatricians from Africa in paediatric endocrinology. Methods. The fellowship is undertaken over an 18-month period: six months of clinical and theoretical training in Kenya, nine months of project research at the fellow's home country, and three months of consolidation in Kenya. Upon completion, certified paediatricians are expected to set up centers of excellence. Results. There have been two phases, phase I from January 2008 to October 2012 and phase II from January 2012 to April 2015. Fifty-four fellows from 12 African countries have been certified, 34 (phase I) and 20 (phase II). Over 1,000 patients with wide ranging diabetes and endocrine disorders have been diagnosed and treated and are being followed up at the centers of excellence. Conclusion. The successes of the PETCA initiative demonstrate the impact a capacity building and knowledge transfer model can have on people in resource-poor settings using limited resources.

Mucosal Blood Group Antigen Expression Profiles and HIV Infections: A Study among Female Sex Workers in Kenya.

BACKGROUND: The ABO blood group antigens are carbohydrate moieties expressed on human red blood cells however; these antigens can also be expressed on some other cells particularly the surface of epithelial cells and may be found in mucosal secretions. In many human populations 80% secrete ABO antigens (termed 'secretors') while 20% do not (termed 'non-secretors'). Furthermore, there are disease conditions that are associated with secretor status. OBJECTIVE: To investigate correlations between secretor status and HIV infection among female sex workers in Nairobi, Kenya. METHODOLOGY: This cross-sectional study recruited 280 female sex workers aged 18-65 years from the Pumwani Majengo cohort, Kenya. Blood typing was determined by serological techniques using monoclonal antibodies to the ABO blood group antigens. Secretor phenotyping was determined using anti-H specific lectins specific to salivary, vaginal and cervical blood group H antigen using the agglutination inhibition technique and correlated to individual HIV sero-status. Participants were additionally screened for Bacterial vaginosis, Neisseria gonorrhoea and Trichomonas vaginalis. RESULTS: Out of the 280 participants, 212 (75.7%) were secretors and 68 (24.3%) were non-secretors. The incidence of all infections: HIV, Bacterial vaginosis, Neisseria gonorrhoea and Trichomonas vaginalis was higher among secretors compared to non-secretors. However, this difference was only statistically significant for HIV infection incidence rates: HIV infected secretors (83.7%) versus HIV un-infected secretors (71.8%) (p = 0.029) Based on ABO phenotype stratification, the incidence of HIV infection was higher among blood group A secretors (26/52 = 50%), in comparison to B (12/39 = 33.3%: p = 0.066), AB (3/9 = 33.3%: p = 0.355), and O secretors (36/112 = 32.1%: p = 0.028). CONCLUSION: This is the first report to document the variable expression of the ABH blood group antigens profiling secretor and non-secretor phenotypes in the female genital tract among a high-risk population in a Kenyan population. These findings suggest the non-secretor phenotype may confer a certain degree of protection against HIV infection.

Induction of Potent and Long-Lived Antibody and Cellular Immune Responses in the Genitorectal Mucosa Could be the Critical Determinant of HIV Vaccine Efficacy.

The field of HIV prevention has indeed progressed in leaps and bounds, but with major limitations of the current prevention and treatment options, the world remains desperate for an HIV vaccine. Sadly, this continues to be elusive, because more than 30 years since its discovery there is no licensed HIV vaccine. Research aiming to define immunological biomarkers to accurately predict vaccine efficacy have focused mainly on systemic immune responses, and as such, studies defining correlates of protection in the genitorectal mucosa, the primary target site for HIV entry and seeding are sparse. Clearly, difficulties in sampling and analysis of mucosal specimens, as well as their limited size have been a major deterrent in characterizing the type (mucosal antibodies, cytokines, chemokines, or CTL), threshold (magnitude, depth, and breadth) and viral inhibitory capacity of HIV-1-specific immune responses in the genitorectal mucosa, where they are needed to immediately block HIV acquisition and arrest subsequent virus dissemination. Nevertheless, a few studies document the existence of HIV-specific immune responses in the genitorectal mucosa of HIV-infected aviremic and viremic controllers, as well as in highly exposed persistently seronegative (HEPS) individuals with natural resistance to HIV-1. Some of these responses strongly correlate with protection from HIV acquisition and/or disease progression, thus providing significant clues of the ideal components of an efficacious HIV vaccine. In this study, we provide an overview of the key features of protective immune responses found in HEPS, elite and viremic controllers, and discuss how these can be achieved through mucosal immunization. Inevitably, HIV vaccine development research will have to consider strategies that elicit potent antibody and cellular immune responses within the genitorectal mucosa or induction of systemic immune cells with an inherent potential to home and persist at mucosal sites of HIV entry.