Transferrin Binding to Peripheral Blood Lymphocytes Activated by Phytohemagglutinin Involves a Specific Receptor

Galbraith, Robert M.; Werner, Philipp; Arnaúd, Philippe; Galbraith, G.M.P.

doi:10.1172/jci109943

Cited by 81 publications

(25 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In primary glial cultures from rat brains, Tf is detected in OLGcs, its expression decreasing after postnatal day 7, in agreement with an increase in MBPand GC-positive cells (Espinosa de los Monteros et al, 1989). In contrast, transferrin receptors are expressed by many neural cell types, and proliferating cells express a much larger number of receptors than resting cells (Galbraith et al, 1980). The expression of the TfR is an early event in OLGc maturation, preceding that of Tf, MBP, or GC.…”

Section: Discussionsupporting

confidence: 65%

Differential effects of apotransferrin on two populations of oligodendroglial cells

Paez

Soto

Pasquini

2003

Glia

View full text Add to dashboard Cite

In the central nervous system (CNS), apotransferrin (aTf) is produced by oligodendroglial cells (OLGcs), and aTf is essential for cell survival. We previously demonstrated that a single intracranial injection of aTf in 3-day-old rats accelerates differentiation of OLGc and that aTf acts at early stages of development on certain populations of OLGcs, promoting accelerated maturation, with no effect on late markers of cell differentiation. The objective of the present study was to analyze OLGc maturation at two different stages of rat development, 4 and 10 days of age, in OLGcs isolated from the brain after intracranial injection of aTf at 3 days of age, and to explore the in vitro effect of aTf added to cultures of OLGc isolated from aTf-injected and control brains. The maturational cell stages were identified by immunocytochemistry with different OLGc markers and by analysis of their morphological complexity. The OLGcs isolated from 4- and 10-day-old animals intracranially injected with aTf were more differentiated than control cells. Treatment with aTf of the cultures of OLGcs that were isolated from 4-day-old saline-injected control animals induced their differentiation, while a similar treatment of the cultures of OLGcs that were isolated from 10-day-old animals did not induce further maturation of the cells. The results presented in the present report demonstrate that the in vivo effects of aTf on OLGc maturation can be reproduced in cultures and that the effects of aTf occur early in development during a narrow, transient "temporal window" within which OLGcs are sensitive to its action.

show abstract

Section: Discussionsupporting

confidence: 65%

Differential effects of apotransferrin on two populations of oligodendroglial cells

Paez

Soto

Pasquini

2003

Glia

View full text Add to dashboard Cite

show abstract

“…It has been suggested (11,39), therefore, that high densities of binding sites are associated only with malignancy or transformation. Other studies, however, performed mainly on mitogen-"stimulated" peripheral blood lymphocytes indicate that transferrin binding sites are markedly increased on all cells during the process of proliferation (12,13,22,27,(40)(41)(42)(43), thus supporting suggestions that more iron is required by dividing cells (44,45). Our studies have not only shown that both normal fibroblasts and leukemic cells in culture have increased density of immunoreactive transferrin receptor molecules slightly proceeding and during the most active state of proliferation, but additionally demonstrate, as opposed to maturing reticulocytes, that "resting," nonproliferating cells still retain about one-fifth to one-third of the immunoreactive receptor molecules.…”

Section: Discussionmentioning

confidence: 99%

Studies of the Transferrin Receptor on both Human Reticulocytes and Nucleated Human Cells in Culture

Frazier¹,

Caskey²,

Yoffe³

et al. 1982

J. Clin. Invest.

126

View full text Add to dashboard Cite

A B S T R A C T The transferrin receptor, present on reticulocytes and nucleated cells in tissue culture, has been measured with both immunoassay techniques and transferrin binding studies. The total cellular immunoreactive receptor is rapidly lost from erythrocytes during the process of reticulocyte maturation (from as many as 400,000 molecules to <20,000 molecules/ reticulocyte). This event parallels the loss of cell surface transferrin binding sites and RNA content, and correlates with previous studies that have measured the decline in hemoglobin synthesis.Nonhemoglobin-producing normal human fibroblasts, which appear to have a much lower iron requirement than reticulocytes, contain similar numbers of immunoreactive receptors per cell (400,000 receptor molecules), when in an active state of proliferation. Although receptor density on fibroblasts is directly related to cell proliferation, our studies demonstrate that nonproliferating fibroblasts still retain significant numbers of immunoreactive receptors (150,000 molecules/ cell) and transferrin binding sites. Since additional studies indicate that proliferating cells have increased iron uptake, a simple hypothesis would predict that the parallel increase in transferrin binding sites and total cellular immunoreactive receptor associated with proliferation is related to an increased cellular iron requirement. However, the number of immunoreactive receptor molecules and transferrin binding sites is not changed when cells are grown in iron-deficient media, or in media with added transferrin-iron. This result and the lack of marked differences in receptor number on both hemoglobin-producing and nonhemoglobin-producing cells indicate that other factors besides receptor density play major roles in the regulation of cellular iron uptake, retention, and loss.

show abstract

“…Iron-saturation of transferrin Human transferrin (iron-free, from Sigma) was iron-saturated by the methods of Galbraith et al (1980) and used in all experiments.…”

Section: Methodsmentioning

confidence: 99%

Interaction of high density lipoproteins with cholesteryl ester-laden macrophages: biochemical and morphological characterization of cell surface receptor binding, endocytosis and resecretion of high density lipoproteins by macrophages.

Schmitz¹,

Robenek²,

Lohmann³

et al. 1985

The EMBO Journal

244

View full text Add to dashboard Cite

cell with a Kd of -9 x 10-7 M. Binding of HDL on the macrophage surface is significantly enhanced in cholesterol-laden macrophages, whereas the increase in the rate of uptake and secretion is less pronounced. Within the HDL fraction the HDL2 subclass showed higher binding, uptake and secretion activity as compared with HDL3. From these experimental data we postulate that cholesterol uptake from macrophages is mediated by HDL particles which interact with these cells via a receptor-mediated retroendocytosis pathway.

show abstract

Transferrin Binding to Peripheral Blood Lymphocytes Activated by Phytohemagglutinin Involves a Specific Receptor

Cited by 81 publications

References 30 publications

Differential effects of apotransferrin on two populations of oligodendroglial cells

Differential effects of apotransferrin on two populations of oligodendroglial cells

Studies of the Transferrin Receptor on both Human Reticulocytes and Nucleated Human Cells in Culture

Interaction of high density lipoproteins with cholesteryl ester-laden macrophages: biochemical and morphological characterization of cell surface receptor binding, endocytosis and resecretion of high density lipoproteins by macrophages.

Contact Info

Product

Resources

About