HOMEPRODUCTSCOMPANYCONTACTFAQResearchDictionaryPharmaSign Up FREE or Login

Studies on red cell aplasia. V. Presence of erythroblast cytotoxicity in G-globulin fraction of plasma.

Abstract
The marrow cells of a patient with pure red cell aplasia markedly increased their rate of heme synthesis when they were freed from the host environment and were incubated in vitro. When the red cell aplasia was treated with cyclophosphamide and prednisone, marrow cell incorporation of (59)Fe into heme in vitro increased several weeks before a reticulocytosis was apparent, and was the earliest effect noted. The plasma gammaG-globulins of this patient inhibited heme synthesis by normal marrow cells or the patient's own marrow cells obtained after remission of the disease. Since the inhibition of heme synthesis could be the result of damage to erythroblasts, the patient's posttreatment marrow cells or normal marrow cells were labeled with (59)Fe and were then incubated with the patient's pretreatment, treatment, and posttreatment gammaG-globulins as well as normal gammaG-globulins. At the end of this incubation the supernatant and cells were separated and counted. Heme was extracted and also was counted. Treatment of the cells with the patient's pretreatment gammaG-globulins resulted in a release of 40% of the radioactive heme from the cells. This represented the loss of radioactive hemoglobin and was an index of erythroblast cytotoxicity. A progressive disappearance of the cytotoxic factor in the gammaG-globulins occurred in the 3 wk period preceding the onset of reticulocytes in the patient's blood. Posttreatment and normal gammaG-globulins did not produce this effect and increased injury of red cells and lymphocytes was not produced by the patient's pretreatment gammaG-globulins. These studies demonstrate a method for measuring erythroblast cytoxicity and show that red cell aplasia is associated with gammaG-globulins that specifically damage erythroblasts. Whether interference with new erythroblast development also occurs and contributes to the inhibition of heme synthesis has not yet been ascertained.
AuthorsS B Krantz, W H Moore, S D Zaentz
JournalThe Journal of clinical investigation (J Clin Invest) Vol. 52 Issue 2 Pg. 324-36 (Feb 1973) ISSN: 0021-9738 [Print] United States
PMID4119161 (Publication Type: Journal Article)
Chemical References
  • Hemoglobins
  • Iron Isotopes
  • gamma-Globulins
  • Erythropoietin
  • Heme
  • Cyclophosphamide
  • Prednisone
Topics
  • Anemia, Aplastic (drug therapy, metabolism)
  • Bone Marrow (metabolism)
  • Bone Marrow Cells
  • Cyclophosphamide (therapeutic use)
  • Erythrocytes, Abnormal (metabolism)
  • Erythropoietin (pharmacology)
  • Heme (analysis, biosynthesis)
  • Hemoglobins (analysis)
  • Humans
  • Iron Isotopes
  • Male
  • Middle Aged
  • Prednisone (therapeutic use)
  • gamma-Globulins (analysis, physiology)

Join CureHunter, for free Research Interface BASIC access!

Take advantage of free CureHunter research engine access to explore the best drug and treatment options for any disease. Find out why thousands of doctors, pharma researchers and patient activists around the world use CureHunter every day.
Realize the full power of the drug-disease research graph!


Choose Username:
Email:
Password:
Verify Password:
Enter Code Shown: