Human diploid fibroblasts have receptors for the globular domain of C1Q

Conference · Sat Mar 01 04:00:00 EST 1986 · Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States)

OSTI ID:5497640

Bordin, S; Page, R C

The authors showed that mass cultures of fibroblasts grown from gingival explants in DB medium with 10% human serum are enriched in a phenotype that binds C1q with an affinity much higher than the rest of the population. Because of potential biologic importance of C1q receptors, the authors studied whether the interaction between C1q and this phenotype was mediated by the globular or collagenous domains of the molecule. Globular fragments were prepared by digesting C1q with collagenase, and collagenous fragments obtained after pepsin treatment. C1q binding on cells in suspension was determined by reaction with /sup 125/I-C1q as reported. Competition experiments were performed under conditions in which intact /sup 125/I-C1q binding saturated all available receptors. The results showed that collagenous fragments inhibited 20% of the /sup 125/I-C1q binding to high affinity receptors, whereas inhibition by globular fragments was 70%. Unlabeled intact C1q and collagen type 1 were used as controls, and inhibited 92% and 17% of C1q binding, respectively. These studies show that C1q interacts with the fibroblast phenotype expressing high affinity receptors through its globular domain. The authors suggest that at sites of trauma, native C1 may bind to the surface of these cells via the globular domain of C1q, and that this unique phenotype may play an important role in tissue repair.

• Research Organization: Univ. of Washington, Seattle
• OSTI ID: 5497640
• Report Number(s): CONF-8604222-
• Conference Information: Journal Name: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States) Journal Volume: 45:3
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ACID PROTEINASES
AFFINITY
ANIMAL CELLS
ANIMALS
BETA DECAY RADIOISOTOPES
BIOCHEMICAL REACTION KINETICS
BIOLOGICAL RECOVERY
BIOLOGICAL REPAIR
CELL CULTURES
COMPLEMENT
CONNECTIVE TISSUE CELLS
DAYS LIVING RADIOISOTOPES
ELECTRON CAPTURE RADIOISOTOPES
ENZYMES
FIBROBLASTS
HYDROLASES
INTERMEDIATE MASS NUCLEI
IODINE 125
IODINE ISOTOPES
ISOTOPE APPLICATIONS
ISOTOPES
KINETICS
MAMMALS
MAN
MEMBRANE PROTEINS
MOLECULES
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
PEPSIN
PEPTIDE HYDROLASES
PHENOTYPE
PRIMATES
PROTEINS
RADIOISOTOPES
REACTION KINETICS
RECEPTORS
RECOVERY
REPAIR
SOMATIC CELLS
TRACER TECHNIQUES
VERTEBRATES