Monoclonal antibody isolation and characterization

我们已经分离并广泛鉴定了近30个恒河猴来源的单抗，其中几个单抗对SIV具有广泛而有效的中和活性。这组新发现的SIV bNAb将能够在SIV NHP模型中使用完全猿猴来源的bNAb来评估HIV-1预防和治疗干预措施，从而绕过与SIV相比，人类来源抗体的mAb快速清除、Fc错配以及SIV基因多样性有限的相关问题。 这些SIV bNAb已用于基于结构的研究：1)确定SIVmac239 gp120的共晶结构，揭示了SIV与HIV-1糖链屏蔽物的功能相似性；2)获得融合前稳定的SIV三聚体的低温EM结构和病毒粒子表面的SIVmac239 Env三聚体的原位结构。 此外，疫苗研究计划(VRP)的试剂承包商实验室(疫苗研究计划(VRP)的试剂承包商实验室、临床前研究和发展处(PRDB)、艾滋病(DAIDS)分部)正在生产几种SIV bNAb，以测试它们是否可以用于：1)受感染猕猴SIV感染的活体成像(Paolo Lusso，M.D.，Ph.D.，免疫调节实验室)；Ii)在NHP模型(Ann Chahroudi，MD，PhD，Emory University School of Medicine)中结合潜伏期反转剂(LRA)和SIV bNAbs的HIV-1治疗策略III)作为bNab治疗(ART)抑制的SIV感染猕猴(Louis Picker，俄勒冈国家灵长类动物研究中心)和iv)被动注射SIV单抗和bNAbs的抗体依赖细胞吞噬(ADCP)和抗体依赖中性粒细胞吞噬(ADNP)的评估(Galit Alter，PhD，麻省理工学院、麻省理工学院和哈佛大学)

We have isolated and extensively characterized nearly 30 rhesus-derived mAbs, several of which mediate broad and potent neutralizing activity against SIV. This panel of newly identified SIV bnAbs will enable evaluation of HIV-1 prophylactic and therapeutic interventions using fully simian, rhesus-derived bnAbs in the SIV NHP model, thereby circumventing issues related to rapid mAb clearance of human-derived antibodies, Fc mismatch and limited genetic diversity of SHIV compared to SIV. These SIV bnAbs have been used in structure-based studies to i) determine the co-crystal structure of SIVmac239 gp120 which revealed functional similarity between the SIV and HIV-1 glycan shields, and ii) obtain a cryo-EM structure of pre-fusion stabilized SIV trimer and an in-situ structure of SIVmac239 Env trimer on the surface of virions. Additionally, several SIV bnAbs are being produced by Quality Biological, Inc., the reagent contractor laboratory for the Vaccine Research Program (VRP), Preclinical Research and Development Branch (PRDB), Division of AIDS (DAIDS), to test whether they can be used for i) in vivo imaging of SIV infection in infected macaques (Paolo Lusso, M.D., Ph.D., Laboratory of Immunoregulation); ii) in a HIV-1 cure strategy combining latency reversal agents (LRA) and SIV bnAbs in a NHP model (Ann Chahroudi, MD, PhD, Emory University School of Medicine) iii) as bnAb therapy administered to (ART)-suppressed SIV-infected rhesus macaques (Louis Picker, Oregon National Primate Research Center) and iv) evaluation of antibody-dependent cellular phagocytosis (ADCP) and antibody-dependent neutrophil phagocytosis (ADNP) of passive administered SIV mAbs and bnAbs (Galit Alter, PhD, Ragon Institute of MGH, MIT, and Harvard)