Linked Life Data

8620548

Source:http://linkedlifedata.com/resource/pubmed/id/8620548

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1996-6-20
pubmed:abstractText
Liposomes act as powerful adjuvants if physically associated with a protein antigen. Their effect on the immune response, however, varies with the nature of this linkage, surface-linked and encapsulated antigens having different properties. Cytometric analysis and cytokine measurements indicate that this difference may be due to the differential activation of T lymphocyte populations. Surface-linked antigen appears to preferentially stimulate CD4+ T cells to proliferate and mature into a typical Th1 phenotype; this is indicated by a positive shift in the CD4+/CD8+ ratio of sensitized splenocytes, a massive production of interferon-gamma, and the absence of interleukin-4 secretion. In contrast, encapsulated antigen, while stimulating spleen cell proliferation, does not significantly affect the CD4+/CD8+ ratio and induces only low levels of interferon-gamma production in the absence of interleukin-4 secretion. These results suggest that CD4+ and CD8+ populations are both expanded in response to encapsulated antigen but that neither typical Th1 nor Th2 phenotypes are induced. High-resolution immunocytochemical investigations show that this differential activation of T cell populations may be related to a different intracellular trafficking of antigens into professional antigen-presenting cells. Whereas surface-linked antigen remains predominantly in endosomal compartments where it may be associated with major histocompatibility (MHC) class II products for presentation to CD4+ T cells, encapsulated antigen escapes into the cytosol, reaching the MHC class I pathway for presentation to CD8+ T cells. The results therefore suggest that both liposomal antigens stimulate cell-mediated immunity albeit differently. This behavioral difference may be of practical importance in the design of adjuvants for the preferential potentiation of specific cytotoxic effector functions.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0008-8749
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
169
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
208-17
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Differential activation of cell-mediated immune functions by encapsulated and surface-linked liposomal antigens.
pubmed:affiliation
Département de Chimie-Biologie, Université du Québec à Trois-Rivières, Canada.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't