Receptor Mobility and Receptor-Cytoplasmic Interactions in Lymphocytes

Abstract

An analysis of the inhibition by concanavalin A of the mobility of lymphocyte surface receptors is used to construct an hypothesis on membrane receptor-cytoplasmic interactions. It is proposed that binding of multivalent lectins alters the interaction of an assembly of colchicine-binding proteins with lectin receptors and other receptors, and reciprocally that the state of the colchicine-binding assembly alters the mobility and distribution of surface receptors on the cell membrane. Observations of the effect of colchicine and related drugs on the inhibition of receptor mobility by concanavalin A lend support to this hypothesis. The proposed model has several implications for studies of the initial events of mitogenesis in lymphocytes as well as for cellcell interactions in general.

Functional interactions of viral and histocompatibility antigens at tumor cell surfaces.

“…After washing, the cells were treated for 10 min at 40 with 1% formaldehyde to prevent further capping (7). The cells were then incubated for 30 min at 40 with 10 ul of rabbit anti-RLV and, after washing, were incubated with goat antibodies to rabbit Ig, labeled with TMR-G anti-R Ig.…”

“…To cap H-2 antigens, 106 tumor cells in 0.15 ml of phosphate-buffered saline (pH 7.4) were incubated with 25 ,ul of anti-H-2 serum for 30 min at 40 and washed and incubated for 10 min at 370 with goat antibodies to mouse Ig labeled with fluorescein (Fl-G anti-M Ig) (7). After washing, the cells were treated for 10 min at 40 with 1% formaldehyde to prevent further capping (7).…”

“…The spleen cells were from donor mice immunized by the subcutaneous injection of 106 irradiated tumor cells [3][4][5][6][7][8] weeks before sacrifice. Cytotoxic lymphocyte activity was determined using a modified 5ICr-release microassay (6).…”

“…Tumor cells (EL4) were incubated with anti-H-2b serum for 30 min at 40, washed, and then incubated for 30 min at 250 with Fl-G anti-M Ig and NaN3 (50 mM) in order to block capping (7). After washing, the cells were treated with 1% formaldehyde to prevent further redistribution of membrane antigens, and viral antigens were stained using sequential incubations at 40 with rabbit anti-RLV previously absorbed with normal spleen cells and TMR-G anti-R Ig.…”

Lymphocyte surface modulation and cyclic nucleotides I. Topographic correlation of cyclic adenosine 3':5'-monophosphate and immunoglobulin immunofluorescence during lymphocyte capping.

“…The participation of microtubules (rigid structures of polymerized tubulin and associated proteins) in the capping process is more controversial (7,8,18). In some instances, microtubular disruption enhances capping; in others it has no effect.…”