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Updated: Aug 9, 2026

In Vitro Assay to Evaluate the Impact of Immunoregulatory Pathways on HIV-specific CD4 T Cell Effector Function
09:26

In Vitro Assay to Evaluate the Impact of Immunoregulatory Pathways on HIV-specific CD4 T Cell Effector Function

Published on: October 16, 2013

Ig VH-dependent interaction between immunoglobulins and CD4

P Lenert1, G Lenert, M Zanetti

  • 1Louis-Charles Simard Research Center, Notre-Dame Hospital, University of Montreal, Quebec, Canada.

International Reviews of Immunology
|January 1, 1997
PubMed

Insights

Interactions between immunoglobulin (Ig) and CD4 molecules can influence T cell activation, leading to either costimulation or inhibition. This study explores CD4

Area of Science:

  • Immunology
  • Molecular Biology
  • Cellular Biology

Background:

  • CD4 is a crucial T cell surface glycoprotein involved in immune responses.
  • CD4 interacts with immunoglobulin (Ig) variable heavy (VH) domains via its C and C strands.
  • These CD4 strands are also vital for binding HIV-gp120 and class II Major Histocompatibility Complex (MHC) molecules.

Purpose of the Study:

  • To hypothesize the impact of high-affinity Ig/CD4 interactions on early T cell activation.
  • To explore the dual outcomes (costimulation and inhibition) of high-affinity Ig/CD4 interactions on T cell proliferation and cytokine secretion.
  • To discuss the role of low-affinity CD4/Ig interactions in B cell stimulation and repertoire shaping.

Main Methods:

  • Review and synthesis of existing experimental data on Ig/CD4 interactions.
  • Hypothetical modeling of Ig/CD4 binding effects on T cell activation pathways.
  • Analysis of CD4's role in B cell receptor-initiated signaling.

Main Results:

  • High-affinity Ig/CD4 interactions can lead to either costimulatory or inhibitory signals in T cells.
  • These interactions differentially affect T cell proliferation and cytokine secretion.
  • Low-affinity CD4/Ig interactions are implicated in B cell activation and repertoire development.

Conclusions:

  • The affinity of Ig/CD4 interactions critically determines the outcome on T cell activation.
  • CD4's interaction with Ig plays a significant role in both T and B cell immunity.
  • Further research is warranted to elucidate the precise mechanisms of CD4's dual role in immune cell regulation.

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