Biological effects of short-term, high-concentration exposure to methyl isocyanate. VI. In vitro and in vivo complement activation studies

Journal Article · Mon Jun 01 04:00:00 EDT 1987 · Environ. Health Perspect.; (United States)

DOI:https://doi.org/10.1289/ehp.8772189· OSTI ID:5898214

Kolb, W P; Savary, J R; Troup, C M; Dodd, D E; Tamerius, J D

The ability of MIC to induce complement activation in vitro and in vivo was investigated. For the in vitro studies, both human and guinea pig serum or EDTA-plasma samples were exposed to 1167 to 1260 ppm MIC vapor for 15 min at room temperature. The human serum samples exposed to MIC showed significant reduction in Factor B, C2, C4, C3, C5, and total hemolytic complement CH/sub 50/ activity levels. The C3, C5, and CH/sub 50/ functional activities in guinea pig serum were more sensitive to MIC-mediated reduction than the corresponding activity reductions observed in the human serum samples. The human and single guinea pig EDTA-plasma samples exposed to MIC vapor showed no evidence of C3 consumption but did show significant reductions in CH/sub 50/ levels. Thus, MIC vapor was able to active, and thereby reduce serum complement C3 activity in vitro by a complement-dependent process. For the in vivo studies, five pairs of guinea pigs were exposed to 644 to 702 ppm MIC vapor until one of the pair died (11-15 min). MIC exposure was then discontinued, the surviving guinea pig was sacrificed, and EDTA-plasma was obtained from both animals and analyzed for complement consumption. Clear evidence was obtained to indicate that complement activation had occurred in these animals exposed to MIC for 11 to 15 min. In addition, the complement activation profile observed in these guinea pigs was qualitatively similar to that seen in the guinea pig serum samples exposed to MIC vapor in vitro. The total protein concentration present in plasma samples obtained from guinea pigs that had died from MIC exposure was elevated significantly. The possible contribution of complement activation to the fatal reaction(s) observed in these MIC-treated animals is discussed.

• Research Organization: Cytotech, Inc., San Diego, CA
• OSTI ID: 5898214
• Journal Information: Environ. Health Perspect.; (United States), Journal Name: Environ. Health Perspect.; (United States) Vol. 72; ISSN EVHPA
• Country of Publication: United States
• Language: English

Related Subjects

560300* -- Chemicals Metabolism & Toxicology
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ACUTE EXPOSURE
ANIMALS
BIOLOGICAL EFFECTS
BLOOD CHEMISTRY
BLOOD SERUM
CHEMICAL ACTIVATION
COMPLEMENT
FLUIDS
GASES
GUINEA PIGS
IN VITRO
IN VIVO
ISOCYANATES
MAMMALS
MAN
MATHEMATICS
ORGANIC COMPOUNDS
PRIMATES
PROTEINS
RODENTS
STATISTICS
VAPORS
VERTEBRATES