Cyclosporine facilitates B-cell membrane immunoglobulin capping.

The immunomodulatory molecule cyclosporine was found to cause an early acceleration of the capping of mouse B-cell membrane immunoglobulin. This was most marked when the capping process was slightly retarded by keeping the cells at 32 degrees. This is a sign that the drug can cause B-cell membrane alterations. At lower drug doses they might not be as easily detected, but are nevertheless sufficient to inhibit the activation of some B cells by membrane immunoglobulin clustering.