The third component of the guinea pig complement system. I. Purification and characterization

Bacterial lipoteichoic acid sensitizes host cells for destruction by autologous complement.

“…Additional experiments were performed in order to examine the apparent discrepancy between the use of EGTA and the use of either C2D HS or C4D GPS to test the ability of LTA-E to by lysed in autologous serum via the alternative pathway. Incubation of optimally sensitized rat LTA-E (50 Ag/ml of LTA) in 50% autologous NRS diluted in GVB-Mg-EGTA gave only 8.4% consumption of C3 (17), indicating that there was no activation of the alternative pathway. In contrast, rat LTA-E incubated in 50% autologous NRS diluted in GVB++ consumed 31% of the C3.…”

“…Veronal-buffered saline without Ca"+ or Mg"+ and containing 0.01 M EDTA was also prepared with 0.1% gelatin (GVB-EDTA) and without gelatin (VBS-EDTA). In some experiments, rat serum was diluted in veronal-buffered saline containing 0.1% gelatin, 3 C3 activity ( 17). Guinea pig serum deficient in the fourth component of complement (C4) was obtained from individual animals with a genetically determined complete deficiency ofC4 (C4D GPS) (18).…”

Complement

“…Consequently, binding occurs only if the transient binding group is exposed in the immediate vicinity of an appropriate accep tor on the cell surface. In studies of C3b bind ing, aromatic hydroxyl compounds were found to be good inhibitors, suggesting that hydroxyl groups might serve as acceptors [38] [12,13] also showed that EAC1 are capable of splitting p-toluenesulfonyl-L-arginine methyl ester (TAME), as well as N-acetyl-/-tyrosine ethylester (ATEE), and that these substrates partially protect activated Cl from inactivation of its hemolytic function by DFP. Thus, the view developed that guinea pig Cl has esterase activity.…”

The Properdin System: Composition and Function

“…In the guinea pig C3 [17], B [18], D [19] and P [20,21] have also been detected. However, there is no report in this species of an initiating factor.…”