Human TcR gamma delta+ lymphocyte response on primary exposure to Plasmodium falciparum

Clin Exp Immunol. 1994 Jan;95(1):91-7. doi: 10.1111/j.1365-2249.1994.tb06020.x.

Abstract

In 29 patients experiencing their first P. falciparum malarial attack, blood levels of TcR gamma delta+ lymphocytes were studied from the onset of infection to up to 6-9 months later. Blood TcR gamma delta+ lymphocytes, revealed using the TcR delta 1 monoclonal antibody (MoAb), were increased both in absolute and relative numbers. Alterations lasted for up to 3-4 months following the attack. A Ti gamma A/BB3 reactive V gamma 9 subset was preferentially amplified. In vitro, TcR gamma delta+ lymphocytes from both malaria-sensitized and unprimed donors responded to P. falciparum schizont extract (PFSE). PFSE-stimulated polyclonal T cell lines consisted principally in TcR gamma delta+ cells with a Ti gamma A+/BB3+ phenotype. Several TcR gamma delta+ T cell clones obtained from patients recovering from acute malarial attack were maintained in the presence of PFSE and autologous irradiated PBL. They belong to the V gamma 9 subset. In long-term cultures, TcR gamma delta+ clones progressively lost their capacity to react to PFSE antigen while they were able to proliferate and to exert cytotoxic activity in response to autologous TcR alpha beta+, PFSE-specific T lymphocyte clones. This suggests that regulatory interactions occur between activated TcR gamma delta+ and TcR alpha beta+ cells generated by P. falciparum. Sequential variations in blood TcR gamma delta+ and TcR alpha beta+ lymphocyte levels after primary exposure to P. falciparum suggest that such regulatory interactions may occur in vivo.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acute Disease
  • Adult
  • Animals
  • Cells, Cultured
  • Female
  • Humans
  • Malaria, Falciparum / immunology
  • Male
  • Middle Aged
  • Plasmodium falciparum / immunology*
  • Receptors, Antigen, T-Cell, alpha-beta / analysis
  • Receptors, Antigen, T-Cell, gamma-delta / analysis*
  • T-Lymphocytes / immunology*

Substances

  • Receptors, Antigen, T-Cell, alpha-beta
  • Receptors, Antigen, T-Cell, gamma-delta