CELL INTERACTIONS BETWEEN HISTOINCOMPATIBLE T AND B LYMPHOCYTES : IV. INVOLVEMENT OF THE IMMUNE RESPONSE (Ir) GENE IN THE CONTROL OF LYMPHOCYTE INTERACTIONS IN RESPONSES CONTROLLED BY THE GENE

In the present study we have asked the question of whether F₁ carrier-primed T cells can serve as helper cells for either or both parental B cells when (a) the carrier molecule employed is under genetic control such that one parental strain is a responder and the other is a nonresponder, and (b) the determinant specificity of the parental B cells being assessed is not under genetic control and bears no relationship to the specificity of the carrier molecule. Utilizing the system of immune response gene control of responses to the terpolymer L-glutamic acid-L-lysine-L-tyrosine (GLT) to which A strain mice (H-2^a) are nonresponders, whereas BALB/c (H-2^d) and (BALB/c x A)F₁ hybrids (CAF₁) are responders, these studies demonstrate that GLT-primed T cells of CAF₁ donors can provide for responder BALB/c, but not for nonresponder A/J, the required stimulus for the anti-DNP responses of DNP-specific B cells of these respective parental strains to the DNP conjugate of GLT. The implications of these findings for Ir gene function in physiologic T-B cell interactions are discussed in detail.