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CD5 signal transduction: positive or negative modulation of antigen receptor signaling

F Lozano1, M Simarro, J Calvo

  • 1Servei d'Immunologia, Institut D'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Hospital Clinic, Villarroel, Barcelona, Spain.

Critical Reviews in Immunology
|December 2, 2000
PubMed

Insights

The CD5 molecule acts as a crucial regulator in immune responses, potentially inhibiting T cell and B cell activation. Further research is needed to understand its complex intracellular signaling pathways and immunomodulatory roles.

Area of Science:

  • Immunology
  • Molecular Biology
  • Cell Signaling

Background:

  • CD5 is a lymphocyte surface glycoprotein functioning as a coreceptor.
  • It modulates antigen-specific receptor-mediated activation and differentiation signals.
  • Previously considered a costimulatory molecule, CD5 may also exert inhibitory functions.

Purpose of the Study:

  • To review recent findings on CD5's immunomodulatory properties.
  • To explore the molecular basis of CD5's context-dependent signaling.
  • To investigate CD5's role in T cell and B cell activation.

Main Methods:

  • Review of recent scientific literature.
  • Analysis of studies on CD5 knockout mice.
  • Examination of intracellular signaling pathways.

Main Results:

  • CD5 exhibits both costimulatory and inhibitory roles.
  • Evidence suggests CD5 attenuates T cell receptor (TCR/CD3) and B cell receptor (BCR) signaling.
  • Differential CD5 functions depend on lymphocyte subset and differentiation stage.

Conclusions:

  • The precise molecular mechanisms underlying CD5's dual role require further investigation.
  • Understanding CD5 signaling is critical for elucidating its immunomodulatory functions.
  • CD5's complex intracellular signaling pathways are an active area of research.

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