FIG. 5.

(A) The presence of purified LPS or HKST does not suppress the ability of T-cell hybridoma 3A9 to respond to hen egg lysozyme. (B) Wild-type LT2 does not abrogate the MHC class I-restricted response of T-cell hybridoma 2B7114 to listeriolysin O (LLO) peptide 91–99. (C) LT2 does not diminish the MHC class II-restricted response of T-cell hybridoma IB5 to listeriolysin O (LLO) peptide 215–234. Purified LPS, heat-killed LT2, heat-killed SA1377, and peptide were added together in various concentrations to hybridoma (10⁵ cells/well) and ConA-elicited macrophages (10⁵/well) in a 96-well format and incubated 24 h. The supernatants were evaluated for IL-2 by using the HT-2 cell line as an indicator. The IL-2 response, recorded in counts per minute (CPM), is expressed as the means ± SD (error bars) for triplicate wells. Because hybridomas are specific, cross reactivity did not interfere with the response as shown.