| First Author | Connelly MA | Year | 2007 |
| Journal | J Leukoc Biol | Volume | 81 |
| Issue | 1 | Pages | 212-20 |
| PubMed ID | 16997854 | Mgi Jnum | J:117272 |
| Mgi Id | MGI:3695883 | Doi | 10.1189/jlb.1005582 |
| Citation | Connelly MA, et al. (2007) Mycobacteria-primed macrophages and dendritic cells induce an up-regulation of complement C5a anaphylatoxin receptor (CD88) in CD3+ murine T cells. J Leukoc Biol 81(1):212-20 |
| abstractText | Complement C5a anaphylatoxin is a potent activator of macrophages, neutrophils, and dendritic cells (DC) and binds the C5a receptor (C5a-R; CD88). Although C5a is chemotactic for T cells, expression of C5a-R on murine T cells has been disputed. We report here that naive, Con A-activated, and cytokine (IL-12, IL-18)-stimulated murine CD3+ T cells from three strains of mice [C57Bl/6, B10.nSn (C5+/+), B10.on (C5-/-)] lacked C5a-R, as evaluated by immunophenotyping with an anti-C5a-R mAb. Ligation of CD3 induced a modest up-regulation with 3% of CD3+ T cells expressing cell surface C5a-R. T cells primed by APC differentiate into effector T cells. Activation of mycobacteria [bacillus Calmette-Guerin (BCG)]-sensitized T cells through MHC II and TCR interactions via BCG-infected macrophages enhanced the expression of C5a-R with approximately 14% of CD3+ T cells positive for C5a-R. Comparable expression was found in C5+/+ as well as C5-/- strains of mice (14% and 15%, respectively). Furthermore, anti-CD3-activated T cells were primed by BCG-infected DC, and a larger proportion of the primed T cells expressed C5a-R (30-40%). Finally, mice infected with BCG showed significant numbers of CD3+ T cells expressing C5a-R in the spleens during infection. As APC, such as macrophages and DC, can secrete C5 and cleave C5 to C5a and C5b through a peptidase, we suggest that macrophage and DC-T cell interactions can up-regulate C5a-R on T cells through MHC II-TCR and provide a C5a peptide for additional local activation of T cells via C5a-R. |
