Teeba Jihad, Xiaoyuan S Chi, Zhiqing He, Kwok Piu Lee, Elie Needle, Jakob Loschko, Jessica Goymer, Helen Wang, Hélène Boigard, Camille Robertson, Jennifer Obregon, Kasey Wilson, Isis Kanevsky, Paul Liberator, Yury V. Matsuka, Mark R. Walter, Kathrin U Jansen, Xinzhen Yang, Philip R. Dormitzer, Kena A Swanson, Nicholas J Buchkovich
A human cytomegalovirus vaccine to prevent congenital disease is a public health priority. We previously demonstrated that vaccine-elicited rhesus CMV (RhCMV) neutralizing titers and T cell responses comparable to natural infection failed to protect from RhCMV infection after experimental oral challenge. Consequently, we established a natural transmission model in which newborn rhesus macaques are co-housed with their RhCMV-positive mothers and immunized five times between 0 and 24 months with gB, pentamer, pp65 and in one group vIL-10. While no significant differences were observed in infection rate between the vaccine and placebo groups at forty weeks after birth, partial protection was observed at week 52 (83.3% infection in placebo, 42.1-50% in vaccine recipients). Within 14 weeks of juvenile macaques transfer to group-housing, all shed RhCMV. These results suggest that the neonatal RhCMV natural transmission model may recapitulate observations in humans immunized with recombinant gB and can be a useful tool for evaluating CMV vaccine candidates.