Prospective monitoring reveals dynamic levels of T cell immunity to Mycobacterium tuberculosis in HIV infected individuals

PLoS One. 2012;7(6):e37920. doi: 10.1371/journal.pone.0037920. Epub 2012 Jun 7.

Abstract

Monitoring of latent Mycobacterium tuberculosis infection may prevent disease. We tested an ESAT-6 and CFP-10-specific IFN-γ Elispot assay (RD1-Elispot) on 163 HIV-infected individuals living in a TB-endemic setting. An RD1-Elispot was performed every 3 months for a period of 3-21 months. 62% of RD1-Elispot negative individuals were positive by cultured Elispot. Fluctuations in T cell response were observed with rates of change ranging from -150 to +153 spot-forming cells (SFC)/200,000 PBMC in a 3-month period. To validate these responses we used an RD1-specific real time quantitative PCR assay for monokine-induced by IFN-γ (MIG) and IFN-γ inducible protein-10 (IP10) (MIG: r=0.6527, p=0.0114; IP-10: r=0.6967, p=0.0056; IP-10+MIG: r=0.7055, p=0.0048). During follow-up 30 individuals were placed on ARVs and 4 progressed to active TB. Fluctuations in SFC did not correlate with CD4 count, viral load, treatment initiation, or progression to active TB. The RD1-Elispot appears to have limited value in this setting.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • CD4 Lymphocyte Count
  • Chemokine CXCL10 / genetics
  • Chemokine CXCL9 / genetics
  • Coinfection / diagnosis
  • Coinfection / immunology
  • Enzyme-Linked Immunospot Assay / methods
  • HIV / immunology
  • HIV Infections / diagnosis
  • HIV Infections / immunology*
  • Humans
  • Limit of Detection
  • Mycobacterium tuberculosis / immunology*
  • Prospective Studies
  • Reproducibility of Results
  • Reverse Transcriptase Polymerase Chain Reaction
  • T-Lymphocytes / immunology*
  • T-Lymphocytes / metabolism
  • Time Factors
  • Tuberculosis / diagnosis
  • Tuberculosis / immunology*
  • Viral Load

Substances

  • CXCL10 protein, human
  • CXCL9 protein, human
  • Chemokine CXCL10
  • Chemokine CXCL9