Antigen receptor triggered upregulation of CD86 and CD80 in human B cells: augmenting role of the CD21/CD19 co-stimulatory complex and IL-4

Cell Immunol. Mar-Apr 2002;216(1-2):50-64. doi: 10.1016/s0008-8749(02)00512-9.

Abstract

The impact of BCR:CD21 co-engagement on B cell expression of molecules critical for T cell activation was investigated with receptor-specific mAbs conjugated to high MW dextran as stimulatory ligands. In the absence of IL-4, BCR:CD21 co-ligation augmented BCR-triggered CD86 only under conditions of very low BCR ligand dose or affinity, and CD80 was minimally induced by BCR and/or CD21 crosslinking. In the presence of IL-4, BCR:CD21 co-ligation augmented CD86 and CD80 expression under conditions of greater BCR engagement. However, with very high level BCR engagement, no bonus effect of BCR:CD21 crosslinking was observed. Co-ligation-promoted CD86 and CD80 expression was associated with heightened B cell activation of resting allogeneic T cells. The data suggest that co-clustering of BCR and the CD21/CD19 co-stimulatory complex following B cell engagement with C3d-bound microbial or self-antigens will enhance B cell recruitment of T cell help only when IL-4 is present and/or BCR engagement is very limiting.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adolescent
  • Antigens, CD / physiology*
  • Antigens, CD19 / physiology*
  • B-Lymphocytes / immunology*
  • B7-1 Antigen / physiology*
  • B7-2 Antigen
  • Child
  • Child, Preschool
  • Dose-Response Relationship, Immunologic
  • Humans
  • Interleukin-4 / analysis
  • Interleukin-4 / biosynthesis
  • Interleukin-4 / physiology*
  • Lymphocyte Activation
  • Membrane Glycoproteins / physiology*
  • Receptors, Antigen, B-Cell / physiology*
  • Receptors, Complement 3d / physiology*
  • Receptors, Interleukin-4
  • T-Lymphocytes / immunology
  • Up-Regulation*

Substances

  • Antigens, CD
  • Antigens, CD19
  • B7-1 Antigen
  • B7-2 Antigen
  • CD86 protein, human
  • Membrane Glycoproteins
  • Receptors, Antigen, B-Cell
  • Receptors, Complement 3d
  • Receptors, Interleukin-4
  • Interleukin-4