Influence of albumin on granulocyte and macrophage colony-forming efficiency.

Abstract

Mouse granulocyte and macrophage precursors were assayed in plasma clot and fibrin clot cultures, and the effect of bovine serum albumin (BSA) on colony formation was investigated. The number of granulocyte colonies (CFU-g) and clusters increased as the albumin concentration was increased and the number of macrophage colonies (CFU-m) and clusters concomitantly decreased. The albumin-mediated suppression of macrophage colony formation was overcome by the addition of more than 10% fetal bovine serum (FBS) to the plasma clot culture. The effect of BSA and fatty-acid-free BSA on colony-forming efficiency was also tested in fibrin clot cultures containing 10% FBS. Both BSA and fatty-acid-free BSA at a final concentration of 0.5-2% enhanced CFU-g colony formation, while both forms of BSA reduced the number of CFU-m colonies. However, neither BSA nor fatty-acid-free BSA had any effect on colony formation in FBS-free fibrin clot cultures, and only BSA enhanced colony formation when transferrin, linoleic acid, alpha-thioglycerol and dextran were added to the culture. The number of CFU-g (15.6 +/- 3.1) was higher in cultures containing BSA, transferrin, etc., than the number (9.8 +/- 2.5) in cultures without BSA and including transferrin, etc., than the number (9.8 +/- 2.5) in cultures without BSA and including transferrin, etc. (p less than 0.01). The number of CFU-m (32.0 +/- 6.8) in cultures containing BSA and the other four factors was lower than the number (72.2 +/- 5.6) in the culture without BSA (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)