Down-regulation of the CD62L antigen as a possible mechanism for neutrophilia during inflammation.

The expressions of both the CD11b/CD18 and CD62L (L-selectin) antigens as well as the absolute number of white blood cells in the peripheral circulating pool of blood in 116 patients with various inflammatory conditions were determined. A highly significant (P<0.0001) negative correlation (r = -0.57) was noted between the absolute number of peripheral blood polymorphonuclear leucocytes and the expression of the CD62L antigen on their surface. In view of the role of CD62L antigen in the rolling of leucocytes along endothelial cells in the microvasculature, its down-regulation might explain, at least in part, the demargination and appearance of neutrophilia during inflammation.