shivs

SHIV stands for simian-human immunodeficiency virus. It is a chimeric lentivirus used in non-human primate research as a model of HIV-1 infection and AIDS. SHIVs combine genetic elements from simian immunodeficiency virus (SIV) with components of human immunodeficiency virus type 1 (HIV-1), most commonly incorporating the HIV-1 envelope glycoprotein (Env) into an SIV backbone. This design enables the virus to enter macaque cells via HIV-1 entry mechanisms while retaining replication characteristics of SIV in the primate host.

SHIVs are used to study viral entry, replication, pathogenesis, and the efficacy of vaccines and antiretroviral therapies in a biologically relevant primate system. They have contributed to evaluating vaccine concepts, broadly neutralizing antibodies, and prevention strategies, particularly for mucosal transmission and antibody-mediated protection. A variety of SHIV strains have been developed to represent different HIV-1 subtypes and entry tropisms, with several well-characterized constructs such as SHIV-89.6P among others, though the field continuously refines and expands the repertoire of available SHIVs.

Construction and safety: SHIVs are engineered under specialized biosafety containment and oversight. Research with SHIVs follows institutional guidelines and national regulations due to the pathogenic potential of HIV-related constructs. Limitations include that SHIVs do not fully recapitulate human HIV-1 infection and disease, and differences between macaque and human immune responses can affect immunogenicity and pathogenesis. Some SHIVs require adaptation to establish durable viremia in macaques.

Despite these limitations, SHIV models remain a valuable tool for preclinical evaluation of vaccines, antibodies, and therapies before human trials, complementing SIV-based models and humanized mouse approaches.