Alternative complement pathway

This convertase, the alternative pathway C3-convertase, although only produced in small amounts, can cleave multiple C3 proteins into C3a and C3b.

C5b binds sequentially to C6, C7, C8 and then to multiple molecules of C9 to form membrane attack complex.

Since C3b is free and abundant in the plasma, it can bind to either a host cell or a pathogen surface.

Age related macular degeneration (AMD) is now believed to be caused, at least in part, by complement overactivation in retinal tissues.

[5] Alternative pathway activation also plays a significant role in complement-mediated renal disorders such as atypical hemolytic uremic syndrome, C3 glomerulopathy, and C3 glomerulonephritis (Dense Deposit Disease or MPGN Type II).