Primary in vitro cytotoxic T cell (CTL) responses were generated against autologous cells modified with 5-iodoacetamidofluorescein (5-AAF-self), 6-iodoacetamidofluorescein (6-AAF-self), and 5-fluorescein isothiocyanate (5-FTC-self). Although all 3 reagents contain fluorescein, 5-AAF and 6-AAF react selectively with free cell surface sulfhydryl groups, whereas 5-FTC reacts predominantly with free cell surface amino groups. Spleen cells from C57BL/10 (H-2b) mice generated strong and H-2-restricted CTL responses against 5-AAF-self and 6-AAF-self, but weak responses against 5-FTC-self stimulation. Spleen cells from B10.BR(H-2(k)) mice exhibited the opposite pattern of high and low responsiveness against these 3 hapten-self immunogens. Antibodies induced against all 3 haptents exhibited extensive cross-reactivity, detected by hemagglutination. However, the CTL against 5-AAF-self, 6-AAF-self, and 5-FTC-self were predominantly specific. Although 5-AAF and 5-FTC were demonstrated to functionally modify distinct cell surface sites, consistent cross-reactive lysis by anti-5-AAF-self CTL against syngeneic 5-FTC targets and, to a lesser extent, vice versa was observed. From these studies, hapten-membrane protein conjugates are visualized consisting of 4 regions: 1) hapten-distal, which includes the part of the hapten farthest from the point of covalent linkage; 2) hapten-proximal, which includes the lower benzene ring where linkage occurs to the protein; 3) hapten-linkage, which includes the thiocarbamyl or acetamido groups; and 4) protein-proximal, which includes the adjacent region of the protein with which the reagent has reacted. The results are discussed with respect to the differential influence of these regions on the specificity of the anti-hapten effectors and Ir gene control of hapten-self CTL responses.
|Original language||English (US)|
|Number of pages||6|
|Journal||Journal of Immunology|
|State||Published - Dec 1 1981|
ASJC Scopus subject areas
- Immunology and Allergy