Red cell destruction by human monocytes--changes in intracellular ferritin concentration and phenotype.
Mononuclear cells from 5 normal men and 5 patients homozygous for hereditary haemochromatosis (HFE) have been incubated for 18 h with or without the addition of sheep red blood cells coated with antibody (SRBC). In the absence of SRBC mean H type ferritin concentrations were greater than L type (normals: mean L type 11.6 ng/10(6) cells, H type 15.5; patients, L type 23.5 ng/10(6) cells, H type 41.6). In the presence of SRBC, monocyte L type ferritin concentrations increased considerably (76 ng/10(6) cells in normals and 141 ng/10(6) cells in patients) but H type ferritin concentrations were the same or decreased compared with incubation in medium only. Incubation with additional iron (ferric ammonium citrate, 2.5 micrograms Fe/ml) increased both H and L type ferritin concentrations. Erythrophagocytosis thus appears to cause differential regulation of H and L ferritin subunit synthesis or breakdown. Normal subjects and patients do not differ in this response to erythrophagocytosis.
Raha-Chowdhury
R
R
Department of Haematology, University of Wales College of Medicine, Cardiff, U.K.
Williams
B J
BJ
Worwood
M
M
D000328:Adult; D000368:Aged; D000818:Animals; D001815:Bloodletting; D002478:Cells, Cultured; D004912:Erythrocytes; D005293:Ferritins / Q000097:blood*; D006432:Hemochromatosis / Q000097:blood* / Q000628:therapy; D006801:Humans; D007501:Iron / Q000097:blood; D007963:Leukocytes, Mononuclear / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000502:physiology; D010587:Phagocytosis; D010641:Phenotype; D012756:Sheep / Q000097:blood
D005293:Ferritins; D007501:Iron