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CD81 (TAPA-1): a molecule involved in signal transduction and cell adhesion in the immune system

S Levy1, S C Todd, H T Maecker

  • 1Department of Medicine, Stanford University Medical Center, California 94305, USA. levy@cmgm.stanford.edu

Annual Review of Immunology
|May 23, 1998
PubMed

Insights

CD81 (TAPA-1) is a cell-surface protein influencing immune cell activation and antibody responses. Its role in B and T cell interactions and integrin signaling highlights its broad biological significance.

Area of Science:

  • Immunology
  • Cell Biology

Background:

  • CD81 (TAPA-1) is a cell-surface protein with diverse biological functions.
  • It is implicated in cell adhesion, morphology, activation, proliferation, and differentiation.

Purpose of the Study:

  • To investigate the multifaceted roles of CD81 in immune cell function and signaling.
  • To explore CD81's association with other cell surface molecules and its impact on immune responses.

Main Methods:

  • Analysis of CD81's role in B cell activation complexes (with CD21, CD19, Leu13).
  • Investigation of CD81's association with T cell co-stimulatory molecules (CD4, CD8, CD3).
  • Assessment of CD81's impact on thymocyte maturation and antibody production in CD81-deficient mice.
  • Examination of CD81's physical and functional association with integrins (VLA-4, LFA-1).

Main Results:

  • CD81 forms complexes that modulate B cell activation thresholds.
  • CD81 supports T cell maturation and provides co-stimulatory signals.
  • CD81-deficient mice show diminished antibody responses.
  • CD81 interacts with integrins, influencing cell adhesion and T cell activation.
  • Anti-CD81 treatment enhances IL-4 synthesis in T cells interacting with B cells.

Conclusions:

  • CD81 plays a critical role in regulating immune cell activation, differentiation, and antibody production.
  • Its interactions with B cell receptor complexes, T cell co-stimulatory molecules, and integrins underscore its importance in adaptive immunity.
  • CD81 is a key player in cell-cell interactions and signaling pathways within the immune system.

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