Expression and distribution of CD11a/CD18 and CD54 during human T cell–B cell interactions

Abstract

Interactions between intercellular adhesion molecule 1 (ICAM-1, CD54) and leukocyte function-associated antigen 1 (LFA-1, CD11a/CD18) play a critical role in T cell-B cell collaboration. The current experiments were carried out to determine the expression and distribution of these adhesion molecules on human peripheral T cells and B cells during T cell-B cell collaboration. Resting CD4+ T cells were largely ICAM-1 negative, whereas immobilized anti-CD3 monoclonal antibody (mAb) rapidly induced ICAM-1 expression. By contrast, most B cells expressed ICAM-1 before activation, and further increases in density were noted with stimulation. Both B cells and CD4+ T cells expressed LFA-1 before activation, although the density on CD4+ T cells was considerably greater. A double staining method for electron microscopic analysis was developed that permitted analysis of the expression and distribution of ICAM-1 to be assessed during T cell-B cell collaboration. Under the experimental conditions examined, B cells showed a uniform distribution of ICAM-1. In contrast, ICAM-1 was highly mobile on the surface of CD4+ T cells. If the T cells were not fixed, staining, even at 4 degrees C, caused rapid redistribution of ICAM-1 into aggregates. However, by fixing cells before the staining procedures, the distribution of ICAM-1 on CD4+ T cells could be accurately assessed. Most (85%) of the fixed activated CD4+ T cells showed a uniform distribution of ICAM-1. However, when activated CD4+ T cells were cocultured with B cells, redistribution of ICAM-1 on CD4+ T cells but not B cells occurred, such that the majority (85%) was found at or immediately adjacent to the point of attachment to the B cells. No redistribution of LFA-1 on either T cells or B cells was found. These findings suggest that rapid changes in density of ICAM-1 expression and the mobility of ICAM-1 on activated T cells may play a role in providing activation signals to B cells during T cell-B cell collaboration.

Spatial distribution of cell adhesion molecules on the peritoneal surface in the cecal perforation‐induced peritonitis

“…ICAM‐1 was localized on the mesothelial cells restricted to their microvilli as well as on the surface of the leukocytes. Thus, the spatial distribution of LFA‐1 and Mac‐1, and of their ligand ICAM‐1 may be involved in leukocyte interaction such as antigen presentation and T cell‐B cell collaboration (Dustin and Springer, 1991; Tohma et al, 1992; Sasaki et al, 1998), and also in leukocyte adhesion to mesothelial cell microvilli. The α 4 distribution suggested the predominance of VLA‐4 on ruffles/microvilli of activated leukocytes, but the possibility could not be excluded that it included α 4 β 7 (LPAM‐1) expression by lymphocytes (Berlin et al, 1995).…”

Mononuclear cell subpopulations in preterm and full-term neonates: independent effects of gestational age, neonatal infection, maternal pre-eclampsia, maternal betamethason therapy, and mode of delivery

“…CD11α, expressed on all mature leucocytes, is an adhesive molecule that mediates migration of the cell into tissue and cell–cell contact [13, 14]. Mature B cells require expression of CD11α also in order to develop into immunoglobulin‐secreting cells: in vitro blocking of CD11α inhibits IgE, IgG, IgM and IgA production [15, 16]. In preterm (or full‐term) babies, high proportions of CD11α − B cells may therefore partially explain their impaired antibody production and susceptibility to infections.…”

Cancer stem cell surface markers on normal stem cells

“…CD114 has been identified as a potential marker for CSCs in neural crest-derived tumors (100, 101). CD54 (intercellular adhesion molecule 1) is related to cell-cell interaction (102); it is not expressed in hESCs, but is weakly expressed in MSCs (103). Although rarely expressed in many normal tissue cells, CD54 is highly detected in the lung, kidney and lymphoid organs (http://www.proteinatlas.org/).…”