Human fibroblasts weakly activated the alternative complement pathway, as assessed by C3b deposition, while 4- to 5-fold more C3b was observed 4 days after infection on cytomegalovirus (CMV)-infected fibroblasts when incubated with human serum. CMV-infected fibroblasts activated via the classical complement pathway independent of specific anti-CMV antibody and incubation of CMV-infected fibrobl...

Background: Photoreceptor cell death due to extensive light exposure and induced oxidative-stress are associated with retinal degeneration. A correlated dysregulation of the complement system amplifies the damaging effects, but the local and time-dependent progression of this mechanism is not thoroughly understood. Methods: Light-induced photoreceptor damage (LD) was induced in Balb/c mice with...

Sclera from donor globes was eluted in phosphate-buffered saline at 4 degrees C for 24 hr. Hemolytic assays were used to measure functional C1, C4, C2, C3, C5 and C6 in scleral eluates. Radial immunodiffusion was used to measure Factor B, a component of the alternative complement pathway, and albumin in scleral eluates. Molecular weight appeared to be a factor in determining the hemolytic activ...

In recent years it has become clear that inflammation and tissue destruction in central nervous system (CNS) disease is due, at least in part, to the activation of complement. Although often implicated in contributing to the pathology of diseases such as multiple sclerosis (MS), Alzhei-mer's disease, and many others, how central the role of complement is to the pathology of these diseases remai...

Candida albicans, an important pathogenic yeast, activates all three pathways of the complement system. To understand how this yeast evades the effects of the activated system, we have analyzed the binding of the classical pathway inhibitor C4b-binding protein (C4BP) by C. albicans. Purified native as well as recombinant C4BP bound dose dependently to the yeast and hyphal forms, as shown by mul...

The complement system consists of more than 40 proteins that participate in the inflammatory response and in pathogen killing. Complement inhibitors are necessary to avoid the excessive consumption and activation of this system on host cells. Leptospirosis is a worldwide zoonosis caused by spirochetes from the genus Leptospira. Pathogenic leptospires are able to escape from complement activatio...

The Lyme disease spirochete, Borrelia burgdorferi, inhabits the gut lumen of the tick vector. At this location the spirochete is exposed to host blood when a tick feeds. We report here on studies that were done with normal and complement-deficient (C3-knockout) mice to determine if the host complement system killed spirochetes within the vector. We found that spirochete numbers within feeding n...

The complement system represents a cascade of serum proteins, which provide a major effector function in innate immunity. Recent studies have revealed that complement links innate and adaptive immunity via complement receptors CD21/CD35 in that it enhances the B cell memory response to noninfectious protein antigens introduced i.v. To examine the importance of complement for immune responses to...