Linked Life Data

8344411

Source:http://linkedlifedata.com/resource/pubmed/id/8344411

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1993-9-7
pubmed:abstractText
The Babesia bovis major merozoite surface antigen (MSA-1) is a 42-kDa integral membrane glycoprotein previously shown to induce immunodominant antibody responses in cattle protectively immune to B. bovis and to induce neutralizing antibody. Recent studies have also shown that MSA-1 B cell epitopes common to New World strains of B. bovis are not present in either Israel or Australia strains. To understand the potential role of this protein in protective immunity, T helper cell responses specific for MSA-1 were characterized in Babesia-immune cattle. Peripheral blood mononuclear cells from immune cattle proliferated against affinity-purified recombinant MSA-1 protein expressed in Escherichia coli. MSA-1 preferentially stimulated the growth of CD4+ T cells in cell lines cultured with antigen for 4 weeks. MSA-1-reactive cell lines responded to a membrane fraction of B. bovis merozoites, suggesting recognition of the native protein. However, B. bovis-reactive T cell lines and T helper clones established by stimulation with crude parasite membrane antigen failed to respond to recombinant MSA-1, indicating that this antigen is not immunodominant for T cells. The majority of MSA-1-specific T helper clones reacted to unfractionated merozoite membrane antigen from New World B. bovis strains, but none of the clones responded to Australia B. bovis or to a Mexico strain of Babesia bigemina. Several T helper clones produced low levels of cytokines when stimulated with concanavalin A and interleukin-2. Northern blot analysis revealed the expression of interleukin-2, interleukin-4, interferon-gamma, and tumor necrosis factor-alpha messenger RNA in mitogen-stimulated T helper clones, showing that the clones examined expressed an unrestricted T helper phenotype. We conclude that the MSA-1 protein, although serologically immunodominant and capable of inducing neutralizing antibodies as well as a T helper cell response, is not an immunodominant T cell antigen. Furthermore, the parasite strain specificity of the Th clones supports previous findings of extensive polymorphism in the MSA-1 glycoprotein and suggests that like B cell epitopes, T cell epitopes reside in a nonconserved portion of the protein.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0014-4894
pubmed:author
pubmed:issnType
Print
pubmed:volume
77
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
97-110
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1993
pubmed:articleTitle
Babesia bovis: characterization of the T helper cell response against the 42-kDa merozoite surface antigen (MSA-1) in cattle.
pubmed:affiliation
Department of Veterinary Pathobiology, Texas A&M University, College Station 77843.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.