Thrombin stimulation of synthesis and secretion of fibronectin by human A549 epithelial cells and mouse LB fibroblasts

Journal Article · Mon Apr 01 04:00:00 EST 1991 · Journal of Histochemistry and Cytochemistry; (USA)

DOI:https://doi.org/10.1177/39.4.2005371· OSTI ID:5946712

Kang, Y H; Kedar, V P; Maheshwari, R K ^[1]

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1. Naval Medical Research Institute, Bethesda, MD (USA)

Thrombin, a serine protease generated at wound sites, takes part in multiple biological functions, including wound healing. The present report elucidates the effect of thrombin on fibronectin (FN) synthesis and secretion in fibroblasts and epithelial cells. Subconfluent cultures of mouse LB fibroblasts and human A549 epithelial cells were exposed to various concentrations of bovine plasma thrombin at 37 degrees C for 16 hr. After exposure, cells were processed for determination of cell-associated and secreted FN by metabolic labeling, immunoprecipitation, immunofluorescence, and peroxidase immunocytochemistry. The correlation of FN production with cell growth was studied by a combined procedure of peroxidase immunocytochemistry and light microscopic autoradiography. The amounts of cell-associated and secreted FN were significantly increased with dose increments of thrombin. The increases were most evident in secreted FN. The increase of cell-associated FN was also evidenced by results from immunofluorescence and immunocytochemical studies. Ultrastructurally, the intracellular FN was localized in rough endoplasmic reticulum, Golgi complexes, and secretory granules, whereas non-released extracellular FN was localized in the plasma membrane of cell-to-cell contacts and in the extracellular fibrils. More intense cytoplasmic FN staining was observed in cells that were not labeled with (3H)-thymidine, indicating that FN production may vary with different phases of cell growth. The results imply that thrombin may play an important role in the early phases of wound healing.

• OSTI ID: 5946712
• Journal Information: Journal of Histochemistry and Cytochemistry; (USA), Journal Name: Journal of Histochemistry and Cytochemistry; (USA) Vol. 39:4; ISSN JHCYA; ISSN 0022-1554
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ANIMAL CELLS
ANIMAL TISSUES
ANIMALS
AUTORADIOGRAPHY
AZINES
BIOASSAY
BIOCHEMICAL REACTION KINETICS
BIOLOGICAL LOCALIZATION
BIOLOGICAL RECOVERY
BIOSYNTHESIS
BODY
CARBOHYDRATES
COAGULANTS
CONNECTIVE TISSUE CELLS
DOSE-RESPONSE RELATIONSHIPS
DRUGS
ENZYMES
EPITHELIUM
FIBROBLASTS
FLUORESCENCE
GLUCOPROTEINS
GLYCOPROTEINS
HEALING
HEMATOLOGIC AGENTS
HEMOSTATICS
HETEROCYCLIC COMPOUNDS
HYDROGEN COMPOUNDS
HYDROLASES
IMMUNOASSAY
INJURIES
KINETICS
LUMINESCENCE
MAMMALS
MAN
MICE
NUCLEOSIDES
NUCLEOTIDES
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PEPTIDE HYDROLASES
PRIMATES
PROTEINS
PYRIMIDINES
REACTION KINETICS
RECOVERY
RIBOSIDES
RODENTS
SACCHARIDES
SERINE PROTEINASES
SOMATIC CELLS
SYNTHESIS
THROMBIN
THYMIDINE
TISSUES
TRITIUM COMPOUNDS
TUMOR CELLS
VERTEBRATES
WOUNDS