title: Immunoglobulin VH gene diversity and somatic hypermutation during SIV infection of rhesus macaques.
abstract: B cell functional defects are associated with delayed neutralizing antibody development in pathogenic lentivirus infections. However, the timeframe for alterations in the antibody repertoire and somatic hypermutation (SHM) remains unclear. Here, we utilized the SIV/rhesus macaque (RM) model to investigate the dynamics of immunoglobulin V(H) gene diversity and SHM following infection. Three RMs were infected with SIVmac239, and V(H)1, V(H)3, and V(H)4 genes were amplified from peripheral blood at 0, 2, 6, 24, and 36 weeks postinfection for next-generation sequencing. Analysis of over 3.8 million sequences against currently available RM germline V(H) genes revealed a highly biased V(H) gene repertoire in outbred RMs. SIV infection did not significantly perturb the predominant IgG1 response, but overall immunoglobulin SHM declined during the course of SIV infection. Moreover, SHM at the AID deamination hotspot, WRC, rapidly decreased and was suppressed throughout SIV infection. In contrast, a transient increase in mutations at the APOBEC3G deamination hotspot, CCC, coincided with a spike in APOBEC3G expression during acute SIV infection. The results outline a timetable for altered V(H) gene repertoire and IgG SHM in the SIV/RM model and suggest a burst of APOBEC3G-mediated antibody SHM during acute SIV infection.
authors.affiliation: Departments of Medicine, Immunology and Microbiology, University of Colorado Denver, Aurora, CO, 80045, USA.
authors.forename: Kejun
authors.initials: K
authors.lastname: Guo
authors.forename: Kalani
authors.initials: K
authors.lastname: Halemano
authors.forename: Kimberly
authors.initials: K
authors.lastname: Schmitt
authors.forename: Miki
authors.initials: M
authors.lastname: Katuwal
authors.forename: Yaqiong
authors.initials: Y
authors.lastname: Wang
authors.forename: Michael S
authors.initials: MS
authors.lastname: Harper
authors.forename: Karl J
authors.initials: KJ
authors.lastname: Heilman
authors.forename: Takeo
authors.initials: T
authors.lastname: Kuwata
authors.forename: Edward B
authors.initials: EB
authors.lastname: Stephens
authors.forename: Mario L
authors.initials: ML
authors.lastname: Santiago
mesh_terms: D000818:Animals; D000916:Antibody Diversity; D001402:B-Lymphocytes / Q000276:immunology*; D001483:Base Sequence; D003564:Cytidine Deaminase / Q000235:genetics; D005787:Gene Frequency; D014644:Genetic Variation / Q000276:immunology; D059014:High-Throughput Nucleotide Sequencing; D007074:Immunoglobulin G / Q000235:genetics / Q000276:immunology; D007143:Immunoglobulin Heavy Chains / Q000235:genetics*; D007075:Immunoglobulin M / Q000235:genetics / Q000276:immunology; D007135:Immunoglobulin Variable Region / Q000235:genetics*; D008253:Macaca mulatta; D017422:Sequence Analysis, DNA; D016097:Simian Acquired Immunodeficiency Syndrome / Q000276:immunology*; D015302:Simian Immunodeficiency Virus / Q000276:immunology; D027041:Somatic Hypermutation, Immunoglobulin / Q000235:genetics*
chemical_list: D007074:Immunoglobulin G; D007143:Immunoglobulin Heavy Chains; D007075:Immunoglobulin M; D007135:Immunoglobulin Variable Region; D003564:Cytidine Deaminase