title: Human macrophage colony-stimulating factor levels are elevated in pregnancy and in immune thrombocytopenia.
abstract: Plasma macrophage colony-stimulating factor (M-CSF) levels were measured by enzyme immunosorbent assay (ELISA) using horse and rabbit polyvalent antibodies raised against human M-CSF purified from urine (hM-CSF). Plasma M-CSF levels in nonpregnant female controls were 364 +/- 69 U/mL (mean +/- SD, n = 20). Pregnancy results in significant elevation of circulating M-CSF levels (541 +/- 164 U/mL, n = 46, P < .0005). M-CSF levels were increased by 28 weeks' gestation and did not increase further in later pregnancy. M-CSF levels were also measured in 20 female controls before and after commencing on the oral contraceptive pill. There was no effect of the contraceptive pill on plasma M-CSF levels (364 +/- 69 U/mL before v 373 +/- 66 U/mL after commencing on the pill). In 28 nonpregnant patients with untreated immune thrombocytopenic purpura, (ITP), plasma M-CSF levels were significantly increased (797 +/- 402 U/mL, n = 28, v 364 +/- 69 U/mL in controls, N = 20, P < .0005). Pregnant ITP patients had higher levels of plasma M-CSF (929 +/- 327 U/mL, n = 25) than nonpregnant patients, but this difference was not significant. Elevated levels of M-CSF in ITP may reflect activation of the reticuloendothelial system (RES), which could result in positive feedback to increase the destruction of platelets. The increase in M-CSF associated with pregnancy could contribute to the exacerbation of latent ITP in pregnancy.
authors.affiliation: Department of Haematology, University College and Middlesex School of Medicine, London, UK.
authors.forename: K
authors.initials: K
authors.lastname: Yong
authors.forename: N
authors.initials: N
authors.lastname: Salooja
authors.forename: R E
authors.initials: RE
authors.lastname: Donahue
authors.forename: U
authors.initials: U
authors.lastname: Hegde
authors.forename: D C
authors.initials: DC
authors.lastname: Linch
mesh_terms: D000328:Adult; D003276:Contraceptives, Oral; D005260:Female; D006801:Humans; D016173:Macrophage Colony-Stimulating Factor / Q000097:blood*; D011247:Pregnancy / Q000097:blood*; D011250:Pregnancy Complications, Hematologic / Q000097:blood*; D011261:Pregnancy Trimester, First; D011262:Pregnancy Trimester, Second; D011263:Pregnancy Trimester, Third; D012016:Reference Values; D013921:Thrombocytopenia / Q000097:blood* / Q000276:immunology
chemical_list: D003276:Contraceptives, Oral; D016173:Macrophage Colony-Stimulating Factor