Author: V. Dimov, M.D., Fellow, Creighton University Division of Allergy & Immunology
Reviewer: S. Randhawa, M.D., Fellow, LSU (Shreveport) Department of Allergy & Immunology
Both participate in leukocyte migration.
Neutrophils extravasate from blood vessels to the site of tissue injury or infection during the innate immune response. Image source: Wikipedia, GNU Free Documentation License.
CD99 (Cluster of Differentiation 99) is also known as MIC2 or single-chain type-1 glycoprotein. CD99 is expressed on all leukocytes but highest on thymocytes and augments T-cell adhesion, apoptosis of double positive T cells, and participates in migration and activation.
CD45 - leukocyte common antigen, present on all hemopoietic cells except erythrocytes
CD44 is a cell-surface glycoprotein involved in cell-cell interactions, cell adhesion and migration. PMN adhesion to the endothelium is mediated through CD44.
Cluster of differentiation (CD) of leukocytes