beta-VLDL-induced alterations in growth potentiating activity produced by mononuclear phagocytes.
This report describes the enhancement of growth potentiating activity produced by mononuclear phagocytes that were incubated with beta-migrating very low density lipoproteins (beta-VLDL). Conditioned media harvested from cultured human peripheral blood monocytes incubated in the presence or absence of the lipoprotein were evaluated for their ability to stimulate DNA synthesis ([3H]thymidine incorporation) of sparsely seeded quiescent BHK-21 (BHK) cells as well as neonatal rat aortic smooth muscle cells (NRSMC). Conditioned media from monocytes incubated in the presence of beta-VLDL enhanced [3H]thymidine incorporation into DNA of both BHK and NRSMC, when compared to conditioned media harvested from monocytes incubated in the absence of beta-VLDL. Studying NRSMC, this effect was evident using media collected from monocytes incubated with lipoprotein for 2 days; however, a longer incubation of monocytes plus lipoprotein was necessary to induce changes in growth potentiating activity for BHK cells. Likewise, the effect of beta-VLDL treatment of thioglycollate broth elicited BALB/c mouse peritoneal macrophages was evaluated. Conditioned media from lipoprotein-treated macrophages exhibited greater growth-stimulating activity for both BHK cells and NRSMC when compared to conditioned media from macrophages incubated in the absence of the lipoprotein. beta-VLDL did not affect viability of the mononuclear cells. These findings further implicate the involvement of the monocyte-derived foam cell in the development of atherosclerosis.
Schreiber
B M
BM
Boston University School of Medicine, Department of Biochemistry, MA 02118.
Martin
B M
BM
Hollander
W
W
Franzblau
C
C
D000818:Animals; D000831:Animals, Newborn; D001011:Aorta / Q000378:metabolism; D002460:Cell Line; D002478:Cells, Cultured; D004247:DNA / Q000096:biosynthesis; D006133:Growth Substances / Q000378:metabolism*; D008079:Lipoproteins, VLDL / Q000494:pharmacology*; D008264:Macrophages / Q000187:drug effects / Q000378:metabolism*; D051379:Mice; D008807:Mice, Inbred BALB C; D009131:Muscle, Smooth, Vascular / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains
D006133:Growth Substances; D008079:Lipoproteins, VLDL; D004247:DNA