| First Author | Alfonso C | Year | 2001 |
| Journal | J Immunol | Volume | 167 |
| Issue | 11 | Pages | 6348-55 |
| PubMed ID | 11714799 | Mgi Jnum | J:72827 |
| Mgi Id | MGI:2153656 | Doi | 10.4049/jimmunol.167.11.6348 |
| Citation | Alfonso C, et al. (2001) The Impact of H2-DM on Humoral Immune Responses. J Immunol 167(11):6348-55 |
| abstractText | H2-DM (DM, previously H2-M) facilitates the exchange of peptides bound to MHC class II molecules. In this study, we have used H2-DM-deficient (DM(-/-)) mice to analyze the influence of DM in the priming of B cell responses in vivo and for Ag presentation by B cells in vitro. After immunization, IgG Abs could be raised to a T-dependent Ag, 4-hydroxy-5-nitrophenylacetyl-OVA, in DM(-/-) mice, but closer analysis revealed the IgG response to be slower, diminished in titer, and composed of low-affinity Abs. The Ab response correlated with a vast reduction in the number of germinal centers in the spleen. The presentation of multiple epitopes by H2-A(b) from distinct Ags was found to be almost exclusively DM-dependent whether B cells internalized Ags via fluid phase uptake or using membrane Ig receptors. The poor B cell response in vivo could be largely, but not completely restored by expression of a H2-Ea(d) transgene, despite the fact that Ag presentation by H2-E(d/b) molecules was found to be highly DM dependent. Hence, while substantial Ab responses can be raised in the absence of DM, this molecule is a crucial factor both for Ag processing and for the normal maturation of T-dependent humoral immune responses in vivo. |
