Feedback regulation of granulopoiesis: Polymerization of lactoferrin abrogates its ability to inhibit CSA production

G. C. Bagby, Robert (Rob) Bennett

Research output: Contribution to journalArticle

21 Citations (Scopus)

Abstract

Neutrophil extracts were prepared from the peripheral blood of 40 normal volunteers and tested for their ability to inhibit CSA production by mononuclear leukocytes. Highly dilute neutrophil extracts inhibited CSA production/release, while extracts selectively depleted of lactoferrin by antibody affinity chromatography did not. In addition, higher concentrations of neutrophil extracts and higher doses of lactoferrin (10-9-10-6 M) failed to inhibit CSA production/release. We found no evidence of CSA or CSA-enhancing factors in either our lactoferrin or our neutrophil extracts. However, using gel chromatography and rate zonal density sedimentation, we noted that lactoferrin undergoes concentration-dependent polymerization at 10-9-10-10 M in tissue culture medium and that while monomeric lactoferrin effectively inhibits CSA production/release in vitro, the polymeric form does not. Thus, while we have confirmed that lactoferrin is the activity in neutrophil extracts that inhibits CSA production, we have also found that lactoferrin undergoes reversible polymerization at physiologic concentrations and that the polymerized molecule is inactive. The tendency of lactoferrin to polymerize in tissue culture medium and in vivo should be taken into account in any studies on its potential role as a physiologically relevant regulator of granulopoiesis.

Original languageEnglish (US)
Pages (from-to)108-112
Number of pages5
JournalBlood
Volume60
Issue number1
StatePublished - 1982
Externally publishedYes

Fingerprint

Lactoferrin
Polymerization
Feedback
Neutrophils
Tissue culture
Culture Media
Affinity chromatography
Mononuclear Leukocytes
Antibody Affinity
Chromatography
Affinity Chromatography
Sedimentation
Gel Chromatography
Healthy Volunteers
Blood
Gels
Molecules
Antibodies

ASJC Scopus subject areas

  • Hematology

Cite this

Feedback regulation of granulopoiesis : Polymerization of lactoferrin abrogates its ability to inhibit CSA production. / Bagby, G. C.; Bennett, Robert (Rob).

In: Blood, Vol. 60, No. 1, 1982, p. 108-112.

Research output: Contribution to journalArticle

Bagby, G. C. ; Bennett, Robert (Rob). / Feedback regulation of granulopoiesis : Polymerization of lactoferrin abrogates its ability to inhibit CSA production. In: Blood. 1982 ; Vol. 60, No. 1. pp. 108-112.
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