HIV-1 infection abrogates CD8+ T cell mitogen-activated protein kinase signaling responses

J Virol. 2011 Dec;85(23):12343-50. doi: 10.1128/JVI.05682-11. Epub 2011 Sep 21.


Mitogen-activated protein kinase (MAPK) signaling pathways are dynamic and sensitive regulators of T cell function and differentiation. Altered MAPK signaling has been associated with the inflammatory and autoimmune diseases lupus and arthritis and with some pathogenic viral infections. HIV-1 infection is characterized by chronic immune inflammation, aberrantly heightened CD8(+) T cell activation levels, and altered T cell function. The relationship between MAPK pathway function, HIV-1-induced activation (CD38 and HLA-DR), and exhaustion (Tim-3) markers in circulating CD8(+) T cells remains unknown. Phosphorylation of the MAPK effector proteins ERK and p38 was examined by "phosflow" flow cytometry in 79 recently HIV-1-infected, antiretroviral-treatment-naïve adults and 21 risk-matched HIV-1-negative controls. We identified a subset of CD8(+) T cells refractory to phorbol 12-myristate 13-acetate plus ionomycin-induced ERK1/2 phosphorylation (referred to as p-ERK1/2-refractory cells) that was greatly expanded in HIV-1-infected adults. The CD8(+) p-ERK1/2-refractory cells were highly activated (CD38(+) HLA-DR(+)) but not exhausted (Tim-3 negative), tended to have low CD8 expression, and were enriched in intermediate and late transitional memory states of differentiation (CD45RA(-) CD28(-) CD27(+/-)). Targeting MAPK pathways to restore ERK1/2 signaling may normalize immune inflammation levels and restore CD8(+) T cell function during HIV-1 infection.

Publication types

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

MeSH terms

  • Adult
  • CD8-Positive T-Lymphocytes / metabolism*
  • CD8-Positive T-Lymphocytes / pathology
  • CD8-Positive T-Lymphocytes / virology*
  • Case-Control Studies
  • Female
  • Flow Cytometry
  • HIV Infections / metabolism*
  • HIV Infections / pathology
  • HIV Infections / virology*
  • HIV-1 / pathogenicity*
  • Humans
  • Lymphocyte Activation
  • Male
  • Mitogen-Activated Protein Kinase 1 / metabolism
  • Mitogen-Activated Protein Kinase 3 / metabolism
  • Mitogen-Activated Protein Kinases / metabolism*
  • Phosphorylation
  • Signal Transduction*
  • Viral Load


  • MAPK1 protein, human
  • Mitogen-Activated Protein Kinase 1
  • Mitogen-Activated Protein Kinase 3
  • Mitogen-Activated Protein Kinases