| First Author | Ziporen L | Year | 2009 |
| Journal | J Immunol | Volume | 182 |
| Issue | 1 | Pages | 515-21 |
| PubMed ID | 19109183 | Mgi Jnum | J:142888 |
| Mgi Id | MGI:3822385 | Doi | 10.4049/jimmunol.182.1.515 |
| Citation | Ziporen L, et al. (2009) Programmed necrotic cell death induced by complement involves a Bid-dependent pathway. J Immunol 182(1):515-21 |
| abstractText | The membrane attack complex (MAC) of the complement system induces a necrotic-type cell death. Earlier findings suggested that Bcl-2 protects cells from MAC-induced necrosis. Here we examined the involvement of Bid, a proapoptotic protein, in MAC-induced cytotoxicity. Bid knockout (Bid-/-) mouse embryonic fibroblasts (MEF) and primary fibroblasts were damaged by complement but to a significantly lower extent than wild-type (WT) fibroblasts. Bid silencing with small interfering RNA duplexes led to elevated resistance of mouse fibroblasts, human K562, and Jurkat cells to lysis by complement. Bid-/- MEF were also resistant to toxic doses of streptolysin O, melittin, and A23187. Analysis of complement protein deposition on fibroblasts demonstrated that less complement C3 and C9 bound to Bid-/- than to WT cells, even though expression of the membrane complement inhibitors Crry and CD59 was relatively reduced on Bid-/- cells. Bid was rapidly cleaved in WT MEF subjected to lytic doses of MAC. Pretreatment of the cells with the pan-caspase inhibitor z-Val-Ala-Asp(OMe)-fluoromethylketone reduced Bid cleavage and cell lysis. These results indicate that complement MAC activates two cell death pathways, one involving caspases and Bid and one that is Bid-independent. |
