Canadian HIV Vaccine Initiative (CHVI) AIDS Vaccine 2012 Boston

1. Innate, Adaptive and Mucosal Immune Responses in HIV-1 Exposed Uninfected Infants: A Human Model to Understand Correlates of Immune Protection Canadian HIV Vaccine Initiative (CHVI) AIDS Vaccine 2012 Boston

2. INFANT Study Innate factors associated (with) nursing transmission

3. The HIV-exposed uninfected infant Development of HIV vaccines has been informed by studies of acute HIV infection, LTNPs, elite controllers, and HIV-exposed uninfected (EU) individuals. Cohorts at high risk of HIV infection, including MSM, CSWs, discordant couples, IDUs have been developed. The EU breastfed infant represents a novel model of studying immune correlates and, unlike other high risk cohorts, HIV exposure thru breastfeeding can be better quantified. The stability of the mother-infant dyad makes them amenable to prospective cohort studies where factors that interfere or enable HIV transmission can be identified.

4. Breastfeeding and HIV Why study mother-to-child transmission? Exclusively breast feed (EBF) infants are 2 to 10-fold less likely to be infected compared to infants who are non-EBF.

5. Hypothesis Short-lived innate factors present in breast milk inhibit vertical transmission of HIV-1 from mother-to-child.

6. Hypotheses Innate immunomodulatory and anti-viral factors in human milk protect infants against HIV infection. Exposure to microbial products in the infants developing gut after mixed breastfeeding leads to immune activation/inflammation and increased susceptibility to HIV infection. Increased innate activation in the mixed breastfed infant will alter innate and adaptive Irs to pediatric vaccinations. Social practices that determine breastfeeding modes will be associated with the level of immune system activation in the EU infant.

7. Study Design A prospective observational cohort study with routine evaluations, standardized questionnaires, relevant maternal & infant biological sampling and comprehensive data collection. 500 HIV+ mother-infant pairs will be followed prospectively from birth to evaluate immune activation, HIV transmission and vaccine responsiveness in the infant in relation to EBF or mixed feeding. BM will be evaluated for innate factors that may alter MTCT via breastfeeding. Also 100 HIV uninfected mothers and their infants followed to evaluate influence of maternal HIV on milk composition, feeding practice and immune activation and vaccine responsiveness in absence of HIV. Also 100 HIV+ mothers and their formula-fed infants enrolled to evaluate ongoing HIV exposure via breastfeeding on immune activation and vaccine response.

8. Study Populations The South African cohort will be recruited from Khayelitsha. Mother-infant pairs will be enrolled at Maternal Obst Unit; est 30-32% deliveries are to HIV-infected mothers. The Nigerian cohort will be recruited from the Plateau State Specialist Hospital. Approx 1/3 of women present at delivery; 20% are HIV-infected.

9. Thus, we aim to identify and describe the barriers and enablers of adherence to feeding guidelines amongst HIV+ women and what parameters mothers would consider in evaluating whether to enroll their HIV uninfected infants into HIV vaccine trials. Unique opportunity to expand our understanding of the factors that would interfere with breastfeeding & willingness of mothers to enroll their infants into vaccine trials.

10. OBJECTIVES To evaluate the role of breastfeeding practice in the EU infant on: HIV transmission Infant gut permeability Mucosal inflammation of the infant gut and oral cavity Systemic immune activation in the infant Stool microbial makeup Immunogenicity of pediatric rotavirus, oral polio and BCG vaccines. To identify breast milk factors associated with: HIV transmission Immune activation in the infant gut HIV-RNA levels in milk HIV inhibition in vitro Maternal HIV infection

11. OBJECTIVES (2) To evaluate the role of mucosal inflammation, systemic immune activation and gut permeability in the EU breast-fed infant on HIV transmission Vaccine responsiveness to Rotavirus, oral polio and BCG vaccines HIV susceptibility following pediatric vaccination

12. OBJECTIVES (3) To evaluate social practices and beliefs regarding breastfeeding mode, MTCT and vaccine testing to determine: The barriers & facilitators to adhering to exclusive and appropriate feeding guidelines to prevent vertical HIV transmission. The various role players involved in decision-making and practice around breastfeeding. Factors that influence the use of infant formula or other supplements by this group of mothers. The key barriers and facilitators to women enrolling their HIV negative infants in a future HIV vaccine trial. The specific decision making process that mothers go thru when deciding whether to enroll their children in a hypothetical HIV vaccine trial.

13. THE TEAM • Dr. Clive Gray – UCT • Dr. Heather Jaspan – UCT • Dr. Jonathan Blackburn - UCT

14. THE TEAM • Dr. Alash’le Abimiku - IHV-Nigeria • Dr. Bill Cameron - U Ottawa • Dr. Blake Ball - U Manitoba/PHAC • Dr. Adam Burgener – PHAC

15. THE TEAM • Dr. Mark Tomlinson - U Stellenbosch • Dr. Ashraf Kagee - U Stellenbosch • Dr. Joel Singer – UBC • Johanna Spaans - U Ottawa

16. Participating Labs: • Nigeria: Plateau State Human Virology Research Center (PLASVIREC) • South Africa: University of Cape Town (UCT) Division of Immunology & Blackburn Lab • Canada: • McMaster Immunology Research Centre & Level III lab • Univ. Manitoba & National Microbiology Laboratories (NML)

17. Innate factors in human milk • Discovery: • Proteomic studies of human milk (HIV+ and HIV-): Drs. Ball & Burgener (Univ. Manitoba & PHAC). • Lipidomic analysis of breast milk: Dr. Blackburn (UCT). • Characterization of innate factors in human milk • Meso Scale Discovery (MSD) multiplex platform: Dr. Rosenthal (McMaster Univ)

18. Training • CAPT Network will be involved in capacity building ensuring broad multilevel training opportunities for junior researchers & research staff. • Good clinical practice training at both clinical sites will be also be provided by CAPTN. • PHAC and UCT will provide lab support training; e.g. lab QA training. • Training exchange programs for HQP. • International exchanges. • Social scientists (Stellenbosch) develop capacity in Nigeria.

19. Concluding remarks This proposal represents a multidisciplinary approach to HIV vaccine research, exploiting the human model of mother-to-child HIV exposure to identify correlates of infant immune protection from infection. Interwoven will be social behavioral approaches of assessing breastfeeding practices and attitudes towards infant vaccinations.

20. Progress • Budget • INFANT STUDY PROTOCOL • Study Operations Manuel • Participant Information Sheet • Consent Forms & CRFs • Table of Specimens • Inter-Institutional Agreements • Sub-Contracts with each Institution/Investigator • IRB & Ethics Approvals • Int’l Clinical Trials Co-ordinator (job description)

21. Research Progress • Successfully received historic breast milk specimens from past feeding study in Nigeria. • Completed initial characterization of innate factors in the milk specimens using multiplex platform. • Identified marked differences between a particular innate factor (sTLR2) in milk from women in North America vs Nigeria and, importantly, between milk from HIV-infected and uninfected women.

22. Canada Africa Prevention Trials Network Meeting – Entebbe, Uganda 2012