Differential expression of insulin like growth factor I and other fibroblast mitogens in porcine colostrum and milk

Conference · Fri May 01 00:00:00 EDT 1987 · Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States)

OSTI ID:6075221

Tan, T J; Simmen, R C.M.; Simmen, F A

Sow mammary secretions contain at least 3 distinct growth factor activities, distinguished by their size and relative abundance in colostrum or later milk. Gel filtration of colostrum in Sephadex G-200 columns, followed by acid-ethanol extraction and radioimmunoassay (RIA) for insulin like growth factor I (IGF-I) revealed high levels of this factor in the 150K and 50K MW regions, characteristic of IGF-I: binding protein complexes. Acid treatment of these fractions yielded free IGF-I peptide (7.5K). Parallel mitogen assays with a fibroblast cell line (AKR-2B) demonstrated a predominant peak of high MW activity (sow colostral growth factor-I, SCGF-I) eluting near the column void volume (MW > 150K). Treatment of SCGF-I with 1M acetic acid resulted in a size reduction of the mitogenic activity (MW < 10K), suggesting association of SCGF-I with a binding protein. The SCGF-I peptide was noncompetitive in IGF-I RIA, was distinct in MW from free IGF-I, and was not mitogenic for chick embryo fibroblasts. Sow milk contains less IGF-I and SCGF-I but does display a predominant peak of small MW (approx. 3K) AKR-2B activity. The changes in expression of these growth factors during lactation may reflect differing roles in lactogenesis and/or neonatal growth and development.

• Research Organization: Ohio State Univ., Wooster
• OSTI ID: 6075221
• Report Number(s): CONF-870644-
• Journal Information: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States), Vol. 46:6; Conference: 78. annual meeting of the American Society of Biological Chemists conference, Philadelphia, PA, USA, 7 Jun 1987
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
PEPTIDE HORMONES
RADIOIMMUNOASSAY
FIBROBLASTS
LACTATION
MAMMARY GLANDS
MILK
MITOGENS
SWINE
ANIMAL CELLS
ANIMALS
BIOLOGICAL MATERIALS
BODY
BODY FLUIDS
CONNECTIVE TISSUE CELLS
DOMESTIC ANIMALS
FOOD
GLANDS
HORMONES
IMMUNOASSAY
IMMUNOLOGY
ISOTOPE APPLICATIONS
MAMMALS
MATERIALS
ORGANS
RADIOASSAY
RADIOIMMUNOLOGY
SOMATIC CELLS
TRACER TECHNIQUES
VERTEBRATES
550201* - Biochemistry- Tracer Techniques