Evaluation of IgG Antibody Production in Rhesus Macaques Challenged with Different Geographical Isolates of Zika Virus

Abstract

Zika virus was declared a public health emergency after the 2015 outbreak in South America resulted in forty-nine deaths and thousands of cases of neurological impairments, such as microcephaly and Guillain-Barré syndrome. The virus has spread from Africa through Asia and into the Americas, with different presentations of disease reported at each destination. Discussed here is the IgG host response to infection with three isolates representative of each clade. Rhesus macaques infected with 1e4, 1e5 or 1e6 PFU of virus displayed comparable titers 10 days after challenge with slightly higher values in macaques challenged with Asian and American isolates. Titers increase significantly fifteen and thirty days after challenge with Asian and American isolates, but the African virus failed to elicit a robust response, regardless of dose. Homozygous and heterozygous re-challenge with American or Asian virus provided an immediate memory-B cell response, while re-challenge with American virus in macaques recovered from African virus infection showed no evidence of protection.