| First Author | Møller-Kristensen M | Year | 2007 |
| Journal | Int Immunol | Volume | 19 |
| Issue | 2 | Pages | 141-9 |
| PubMed ID | 17182967 | Mgi Jnum | J:117801 |
| Mgi Id | MGI:3697753 | Doi | 10.1093/intimm/dxl131 |
| Citation | Moller-Kristensen M, et al. (2007) Cooperation between MASP-1 and MASP-2 in the generation of C3 convertase through the MBL pathway. Int Immunol 19(2):141-9 |
| abstractText | The complement system is an important part of the innate immune system. Three pathways, the classical, the alternative and the lectin pathway, lead to the cleavage of complement factor C3, a central event in the activation of the complement system. We investigated the deposition of C3b (solid-phase C3 activation product) on a mannan-coated surface at high concentration of human serum (17%). At these conditions, mannan-binding lectin (MBL) promoted the activation of C3 through the combined action of MBL-associated serine protease (MASP)-1 and MASP-2 without appreciable involvement of the alternative pathway. In serum depleted of MASP-1, MASP-2 and MASP-3, we observed synergetic effect of reconstitution with MASP-1 and MASP-2. This was inhibited by MASP-3. No C3b deposition was observed with C2- or C4-depleted serum. Depletion of factor B had no effect on the MBL-MASP-promoted C3b deposition. Our results demonstrate a function of the orphan protease MASP-1 by providing evidence that this enzyme collaborates with MASP-2 in the generation of C3 convertase, a process observable at high serum concentration, but not at low serum concentration. |
