Skip to content


You're viewing the new version of our site. Please leave us feedback.

Learn more

BMC Infectious Diseases

Open Access

A prospective analysis of viral immune escape in the chronic phase of the subtype C HIV-1 infections of India

  • Shilpee Sharma1,
  • Pachamuthu Balakrishnan2,
  • Suniti Solomon2 and
  • Udaykumar Ranga1Email author
BMC Infectious Diseases201212(Suppl 1):P25

Published: 4 May 2012


HIV-1 is capable of evading CTL immune response through mutations in residues both within the epitopes and in sequences flanking the epitopes leading to viral diversity - a major obstacle for vaccine design. The present study aims at identifying the HLA-restricted CTL escape mutations primarily in the asymptomatic phase, and examining a correlation between such mutations and disease progression.


In a prospective study, a cohort of select seropositive drug-naive subjects categorized into one of three clinical groups (long-term non-progressors, regular progressors and rapid progressors), based on the archived clinical records at YRG CARE, are being monitored for two years with repeated sampling at 6-month intervals. The phylogenetic analysis of the gag sequences was inferred using the Neighbour-Joining method in MEGA 5 to monitor viral evolution and to study CTL escape. ELISPOT will be used for mapping of the immunodominant CTL epitopes in gag with an emphasis on identifying a possible correlation between such immune responses and disease progression.


Twenty plasmid clones of gag have been sequenced from ten patients each at the base level. Escape mutants in several known immunodominant CTL epitopes have been identified in many of the subjects. The viral isolates phylogenetically clustered with the reference subtype C sequences. Additionally, multiple sequences from individual viral isolates clustered together indicating genetic-relatedness. Sequence analysis with REGA HIV-1 Subtyping Tool further confirmed the subtype C identity of all the viral isolates.


The preliminary data are suggestive of viral escape in the chronic phase of the viral infection.

Authors’ Affiliations

Jawaharlal Nehru Centre for Advanced Scientific Research, HIV-AIDS Laboratory
YRG Centre for AIDS Research and Education


© Sharma et al; licensee BioMed Central Ltd. 2012

This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.