Combined immunodeficiency due to the selective absence of CD4 inducer T lymphocytes.

Journal Article

Selective congenital deficiency of the CD4 inducer T lymphocyte subset is a recently described variant of combined immunodeficiency. To further characterize the cellular and molecular mechanisms which lead to the profound T and B cell immunodeficiency in this condition, we examined in vitro immunoregulatory T lymphocyte activation and effector function, interleukin-2 (IL-2) synthesis, IL-2 receptor generation, and CD4 gene structure. Immunophenotyping of T lymphocytes demonstrated a selective deficiency of CD4+ cells, with normal numbers of CD2+ and CD3+ T cells, nearly all of which expressed the CD8+ determinant. Mitogen- and alloantigen-induced blastogenesis was profoundly decreased. B lymphocytes were present in normal numbers but there was a functional dysgammaglobulinemia (low IgG, normal IgM, low IgA) with no antibody response to in vivo immunization. T cells from the patient did not provide help to normal B cells for in vitro immunoglobulin synthesis; however, the patient's B cells were capable of synthesizing normal amounts of IgG when provided help from normal T cells. Concanavalin A failed to activate suppressor-inducer function in the patient's T cells. However, CD8+ T cell-mediated suppression was expressed if the patients T cells were cocultured with normal CD4+ T cells in a pokeweed mitogen-stimulated IgG secretion assay. IL-2 secretion and IL-2 receptor expression were both markedly reduced. Southern blot analysis of genomic DNA revealed no obvious abnormality in CD4 gene structure. The global defects in T cell activation, effector function, immunoregulation, and lymphokine generation observed in CD4+ inducer lymphocyte deficiency emphasizes the central role that the CD4 T lymphocyte plays in the activation and regulation in vivo immune responses.

Full Text

Duke Authors

Cited Authors

  • Sleasman, JW; Tedder, TF; Barrett, DJ

Published Date

  • June 1, 1990

Published In

Volume / Issue

  • 55 / 3

Start / End Page

  • 401 - 417

PubMed ID

  • 1971201

International Standard Serial Number (ISSN)

  • 0090-1229

Language

  • eng

Conference Location

  • United States