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PubMed · 3487199

Large, but not small, antigens require time- and temperature-dependent processing in accessory cells before they can be recognized by T cells.

S Buus·O Werdelin
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Abstract

We have studied if antigens of different size and structure all require processing in antigen-presenting cells of guinea-pigs before they can be recognized by T cells. The method of mild paraformaldehyde fixation was used to stop antigen-processing in the antigen-presenting cells. As a measure of antigen presentation we used the proliferative response of appropriately primed T cells during a co-culture with the paraformaldehyde-fixed and antigen-exposed presenting cells. We demonstrate that the large synthetic polypeptide antigen, dinitrophenyl-poly-L-lysine, requires processing. After an initial time-lag of 30 min this antigen is fully processed within 2 to 4 of culture at 37 degrees C. In contrast, the immunogenic heptapeptide, angiotensin III, can be presented by pre-fixed accessory cells, viz. without any prior processing. Antigen processing was found to be temperature-dependent and consequently energy-requiring. Processing is strongly inhibited by the lysosomotrophic drug, chloroquine, suggesting a lysosomal involvement in antigen processing. The existence of a minor, non-lysosomal pathway is suggested, since small amounts of antigen were processed even at 10 degrees C, at which temperature no transport to and from the lysosomes can occur.

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Angiotensin IIIAnimalsAntigen-Presenting CellsAntigensChloroquineDinitrobenzenesFormaldehydeGuinea PigsInterleukin-1Molecular WeightOvalbuminPolylysinePolymersT-LymphocytesTemperatureTime FactorsTuberculinComparative StudyJournal ArticleResearch Support, Non-U.S. Gov't

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S Buus, O Werdelin. 1986. Large, but not small, antigens require time- and temperature-dependent processing in accessory cells before they can be recognized by T cells.. https://doi.org/10.1111/j.1699-0463.1986.tb02084.x

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