Production of soluble CD23 from peripheral blood lymphocytes of asthmatic patients.

The low-affinity receptor IgE (Fc epsilon RII) as shown to be identical to CD23 several years ago. The presence of the CD23 was demonstrated on a variety of human cells, such as T cells, monocytes, eosinophils, platelets, lymphocytes B, etc., and it can be cleaved in soluble fragments. We studied the in vitro production of soluble CD23 (sCD23) in PBMC of patients with bronchial asthma and in healthy donor cells. If we stimulate production with a polyclonal activator [Phytohemagglutinin (PHA) at a concentration of 10 micrograms/ml], it can be seen that the greatest amounts of sCD23 are produced on the fourth day and that production is greater in asthmatic patients than in control group (p < 0.01). When stimulated additionally by an antigen, the production of sCD23: Is greater when stimulated with PHA. Is released in quantities greater than in healthy group cells, when the PBMC are stimulated with the antigen to which the patients are sensitive (olive pollen). The quantity released depends on the concentration of the antigen added to the culture. Is not released in greater quantities by healthy groups cells in the presence of the antigen than in healthy group cells without the antigen. Is not released in greater quantities by cells of asthmatics in the presence of an antigen to which they are not sensitive (D. pteronyssinus). This leads us to conclude that the release of sCD23 in these patients could play a role in the physiopathology of extrinsic bronchial asthma.