Single B cells reveal the antibody responses of rhesus macaques immunized with an inactivated enterovirus D68 vaccine

Abstract

Enterovirus D68 (EV-D68) infection may cause severe respiratory system manifestations in pediatric populations. Because of the lack of an effective preventive vaccine or specific therapeutic drug for this infection, the development of EV-D68-specific vaccines and antibodies has become increasingly important. In this study, we prepared an experimental EV-D68 vaccine inactivated by formaldehyde and found that the serum of rhesus macaques immunized with the inactivated EV-D68 vaccine exhibited potent neutralizing activity against EV-D68 virus in vitro. Subsequently, the antibody-mediated immune response of B cells elicited by the inactivated vaccine was evaluated in a rhesus monkey model. The binding activity, in vitro neutralization activity, and sequence properties of 28 paired antibodies from the rhesus macaques' EV-D68-specific single memory B cells were analyzed, and the EV-D68 VP1-specific antibody group was found to be the main constituent in vivo. Intriguingly, we also found a synergistic effect among the E15, E18 and E20 monoclonal antibodies from the rhesus macaques. Furthermore, we demonstrated the protective efficacy of maternal antibodies in suckling C57BL/6 mice. This study provides valuable information for the future development of EV-D68 vaccines.

VDJ Gene Usage in IgM Repertoires of Rhesus and Cynomolgus Macaques

“…In recent years, macaques were used to isolate neutralizing monoclonal antibody responses to several human vaccine targets, including HIV-1 ( 12 ), dengue virus, HCV ( 40 ), Ebola ( 46 ) and Enterovirus D68 ( 47 ). While B cell responses elicited by immunization are usually highly polyclonal with many alternative VDJ recombinations, we know from human studies that certain classes of neutralizing antibodies utilize a restricted set of IGH germline genes ( 48 ).…”

Animal Models of Enterovirus D68 Infection and Disease

“…Passive immunization studies in mouse models have suggested that hyperimmune sera or purified monoclonal antibodies isolated from challenged animals are protective against homologous challenge in naive animals ( 42 , 43 ). Moreover, data from these studies suggest that anti-EV-D68 antibodies are broadly neutralizing, and may protect against multiple EV-D68 strains ( 44 , 45 ). Similar studies in cotton rats, however, have shown that immunization with inactivated EV-D68 confers either no protection or enhanced disease following challenge ( 35 ).…”

“…EV-D68 challenge in neonatal mice ( 43 ). In a similar study, 6-month-old rhesus macaques immunized with a formaldehyde-inactivated EV-D68 vaccine were used for isolation of memory B cells to evaluate ex vivo binding and neutralization activity of specific monoclonal antibodies ( 45 ). Neither study reported any respiratory or neurologic disease following infection.…”

Different T-cell and B-cell repertoire elicited by the SARS-CoV-2 inactivated vaccine and S1 subunit vaccine in rhesus macaques

“…The B-cell repertoire (BCR) immunoglobin heavy chain (IGH) genes of SARS-CoV-2 specific B sorted from different vaccines were amplified from the cDNA by 2 rounds of nested PCR according to a previously established method. 11 , 12 The PCR products were evaluated on 2% agarose gels, and the positives (bands 300~500 bp for IGH gene) were sequenced. The IGH VDJ genes and the CDR3 length were analyzed using IgBLAST ( https://www.ncbi.nlm.nih.gov/igblast/ ).…”