Linked Life Data

2565244

Source:http://linkedlifedata.com/resource/pubmed/id/2565244

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1989-6-2
pubmed:abstractText
In this study we further define cell surface carbohydrate structures relevant to cellular interactions that regulate erythropoiesis. An analysis of thymocyte cell surface negativity was made using fluoresceinated poly-L-ornithine (FITC poly-L-ornithine) as a probe that binds to negatively charged sites (i.e., sialic acid residues) at the cell surface. Two distinct subpopulations are labeled, comprising both intensely as well as weakly fluorescent subpopulations of thymocytes. Prior treatment of thymocytes with Vibrio cholerae neuraminidase (VCN), which removes cell surface sialic acid residues, markedly reduced the FITC poly-L-ornithine surface labeling of these cells. Distinct enzymatic modifications of regulatory cell functions were also assessed by the ability of thymocytes to function as separate regulatory subpopulations. Confirming our previous observations, treating thymocytes with VCN impaired the enhancement activity but had little effect on thymocyte regulatory ability to suppress erythroid colony growth. In contrast, treatment of thymocytes with galactose oxidase (GAO) or beta-galactosidase (beta-GAL) removed suppressor activity either before or after VCN treatment. A further exposure of GAO-treated thymocytes to sodium borohydride or hydroxylamine, which reduce D-galactose residues, restores their suppressor function and prevents enhancement. These differential enzymatic effects on thymocyte regulatory cell functions suggest that different carbohydrate structures may be involved in helper and suppressor activities for erythroid colony formation. Sialic acid residues may be associated with certain cells that function to enhance erythropoiesis, and D-galactose residues may be associated with the suppressor subpopulation.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0301-472X
pubmed:author
pubmed:issnType
Print
pubmed:volume
17
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
351-6
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1989
pubmed:articleTitle
Effects of neuraminidase on the regulation of erythropoiesis: III: Characterization of carbohydrate moieties on the surface of thymic regulatory cells that interact with erythroid colony-forming cells.
pubmed:affiliation
Department of Experimental Hematology, Johns Hopkins University School of Medicine, Baltimore, Maryland.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.