| First Author | Nitschke L | Year | 1999 |
| Journal | J Exp Med | Volume | 189 |
| Issue | 9 | Pages | 1513-8 |
| PubMed ID | 10224292 | Mgi Jnum | J:76972 |
| Mgi Id | MGI:2180690 | Doi | 10.1084/jem.189.9.1513 |
| Citation | Nitschke L, et al. (1999) Identification of CD22 ligands on bone marrow sinusoidal endothelium implicated in CD22-dependent homing of recirculating B cells. J Exp Med 189(9):1513-8 |
| abstractText | CD22 is a B cell-specific transmembrane protein known to function as a negative regulator of B cell signaling. It has also been implicated in cell adhesion through recognition of alpha2,6-linked sialic acids on glycans of target cells. Previous studies showed that CD22-deficient mice had a strongly reduced population of mature recirculating B cells in the bone marrow despite normal B cell development. Using a soluble recombinant form of the receptor (CD22-Fc), we demonstrate here that sialylated ligands for CD22 are expressed on sinusoidal endothelial cells of murine bone marrow but not on endothelial cells in other tissues examined. Injection of CD22-Fc revealed that the CD22 ligands in the bone marrow were accessible to the circulation. Treatment of mice with either CD22-Fc or affinity-purified anti-CD22 antibody led to an approximately 50% reduction in mature recirculating B cells in the bone marrow without affecting numbers in the spleen. Finally, consistent with the notion that CD22 is a homing receptor, we show that compared with wild-type mice, CD22-deficient animals have a lower number of immunoglobulin M-secreting plasma cells in the bone marrow. |
