GARG Himanshu

HIV-1 subtype CRF01_AE and B differ in utilization of low levels of CCR5, Maraviroc susceptibility and potential N-glycosylation sites

Published date : 09 Oct 2017

HIV subtypes not only predominate in different geographical regions but also differ in key phenotypic characteristics. To determine if genotypic and/or phenotypic differences in the Envelope (Env) glycoprotein can explain subtype related differences, we cloned 37 full length Envs from Subtype B and AE HIV infected individuals from Singapore. Our data demonstrates that CRF01_AE Envs have lower Potential N Glycosylation Sites and higher risk of ×4 development. Phenotypically, CRF01_AE were less infectious than subtype B Envs in cells expressing low levels of CCR5.

type
Journal Paper
journal
Virology, 512, 2017 December, Pg 222-233, doi: 10.1016/j.virol.2017.09.02
Impact Factor
3.353

HIV-1 adaptation to low levels of CCR5 results in V3 and V2 loop changes that increase envelope pathogenicity, CCR5 affinity and decrease susceptibility to Maraviroc

Published date : 24 Mar 2016

Variability in CCR5 levels in the human population is suggested to affect virus evolution, fitness and the course of HIV disease. We previously demonstrated that cell surface CCR5 levels directly affect HIV Envelope mediated bystander apoptosis. In this study, we attempted to understand HIV evolution in the presence of low levels of CCR5, mimicking the limiting CCR5 levels inherent to the host. HIV-1 adaptation in a T cell line expressing low levels of CCR5 resulted in two specific mutations; N302Y and E172K.

type
Journal Paper
journal
Virology. 2016 Mar 24; 493:86-99. doi: 10.1016/j.virol.2016.03.010
Impact Factor
3.2

Genetic Signatures of HIV-1 Envelope Mediated Bystander Apoptosis

Published date : 21 Nov 2013

The Envelope (Env) glycoprotein of HIV is an important determinant of viral pathogenesis. Several lines of evidence support the role of HIV-1 Env in inducing bystander apoptosis that may be a contributing factor in CD4+ T cell loss. However, most of the studies testing this phenomenon have been conducted with lab adapted HIV-1 isolates. This raises the question whether primary Envs derived from HIV infected patients are capable of inducing bystander apoptosis and whether specific Env signatures are associated with this phenomenon.

type
Journal Paper
journal
The Journal of Biological Chemistry, 21 Nov 2013, doi:10.1074/jbc.M113.514018
Impact Factor
4.651

Identification of conserved motifs in the Westnile virus envelope essential for particle secretion

Published date : 04 Sep 2013

BACKGROUND:

Enveloped viruses utilize cellular membranes to bud from infected cells. The process of virion assembly and budding is often facilitated by the presence of certain conserved motifs within viral in conjunction with cellular factors. We hence examined the West Nile Virus (WNV) Envelope protein for the presence of any such motifs and their functional characterization.

RESULTS:

type
Journal Paper
journal
BMC Microbiology 2013 Sep 4;13(1):197
Impact Factor
3.1