COMPLEMENT IN HUMAN SERUM

Human corneal extract enhances serum complement activity.

PURPOSE The concomitant presence of complement-activation products in the cornea during inflammation is well described. The present study was undertaken to analyze the complement activity of normal human corneal tissue and to assess the presence of complement-modulating activities. METHODS Human corneal tissue was extracted in veronal-buffered saline. The overall complement (C) activity of th...

Complement Interaction with Trypanosomatid Promastigotes in Normal Human Serum

In normal human serum (NHS), axenic promastigotes of Crithidia, Phytomonas, and Leishmania trigger complement activation, and from 1.2 to 1.8 x 10(5) C3 molecules are deposited per promastigote within 2.5 min. In Leishmania, promastigote C3 binding capacity remains constant during in vitro metacyclogenesis. C3 deposition on promastigotes activated through the classical complement pathway reache...

The Complement-dependent Bacteriolytic Activity of Normal Human Serum

The bacteriolytic activity of normal human serum on a rough strain of E. coli has been studied by a turbidimetric method. Bacteriolysis was found to be markedly dependent on ionic strength and pH, with optima at micro = 0.06 and pH 8.3-8.5, respectively. The method of cultivating the cells also influenced the rapidity of lysis. Lysis was temperature-dependent and was exhibited by all samples of...

Serum complement after orthotopic transplantation of the human liver.

Neisseria meningitidis NalP cleaves human complement C3, facilitating degradation of C3b and survival in human serum.

The complement system is a crucial component of the innate immune response against invading bacterial pathogens. The human pathogen Neisseria meningitidis (Nm) is known to possess several mechanisms to evade the complement system, including binding to complement inhibitors. In this study, we describe an additional mechanism used by Nm to evade the complement system and survive in human blood. U...