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A variety of tumor associated antigens have been detected on plasma cell tumors (PCTs). In an attempt to obtain homogeneous populations of cytotoxic T cells which are specific for individual PCT antigens, several continuous cytotoxic T lymphocyte lines (CTLLs) have been generated. These lines show a substantial enrichment of cytotoxic activity against the tumor cell line against which they were generated as compared to cytotoxic T cells generated in a primary in vitro induction. In addition, these lines show different patterns of reactivity from one another when tested against a range of tumor cell targets which are known to share antigens in common with the stimulating PCT. These CTL lines may be of considerable value in further studies on major histocompatibility restriction of cytotoxic T cell responses to individual PCT antigens.

Publisher Summary This chapter illustrates several ways in which radiation may be employed to dissect several individual cellular components of the immune response. The chapter considers the interrelationships between radiation and the various components of the immune response from three perspectives: (1) the effect of irradiation on normal lymphoid tissues and on isolated lymphocytes, (2) the effect of irradiation on antibody production, transplantation immunity, and other forms of cellular immunity, and (3) the effect of irradiation upon tolerance with specific references to putative autoimmune consequences after radiation-induced alterations in normal immunological homeostasis. A wide variety of approaches are available to characterize and define distinct populations of lymphocytes. These include biophysical and functional methods and characterization of antigenic and cell surface receptor components. The mechanisms of radiation effects in biological systems, particularly in humans, have been derived from experiments utilizing cells exposed in vitro and maintained in tissue culture. Such cells can be examined for: (1) loss of viability, (2) alterations in biophysical structure, (3) loss of functional capabilities, (4) biochemical changes, and (5) evidence of injury to subcellular components.

Publisher Summary This chapter describes membrane immunoglobulins and antigen receptors on B and T lymphocytes. There are several qualitative and quantitative distinctions between T-cell and B-cell M-Ig that may explain many of the apparent differences in reactivity of these cells without requiring the existence of a different set of V genes or non-Ig receptors in T cells. Both T and B cells derive from hematopoietic, precursor, stem cells by antigen-independent differentiation. This involves the activation of L-chain and p-type H-chain genes in both cell types. The T-cell and B-cell M-Ig differ primarily in density per cell and possibly in relative exposure on the cell surface with much of the H-chain Fc region inaccessible on T cells. Moreover, the antigen-recognition receptor of both T and B cells involves their M-Ig. On B cells, the receptor is solely the M-Ig, whereas on T cells it is suggested that the specificity of recognition controlled primarily by the M-Ig and binding of antigen to the cell can solely be by the M-Ig receptor. Finally, the activation of the T cell requires an additional interaction of the antigen with another ceIl surface structure that is coded for by a polymorphic H-2 linked gene.