For more than ten years cell fusion techniques have been applied in studies on various lymphocyte functions. Ig expression was first studied in hybrids obtained by fusing myeloma cells with fibroblasts (1) or lymphomas (2), both of which do not produce Ig, and with Ig producing myelomas (3) or human blood lymphocytes (4). Kohler and Milstein (5) fused a myeloma with spleen cells from immunized mice. Up to 10% of the hybrids obtained secreted antibodies specific for the immunizing antigen. This suggested that plasma cells preferenti ally fused with the myeloma cells, a finding which was of enormous practical value. It was found that both Band T lymphocytes could be fused with the T cell tumor BW5147, which is however not permissive for Ig synthesis (6). A very large number of T cell hybridomas were generated by fusing BW5147 with cell populations containing in vivo or in vitro activated cells (7). The hybrids showed no specific T cell functions and binding assays for T cell receptorswere not available. In particular, no hybrids were obtained which expreS1ed specific cytolytic activity that could be tested in short-term Cr release assays (8). However, the frustrations expressed about these failures, published in January, 1978 (9), were relieved by Taniguchi and Miller's publication a few months later of T cell hybridomas producing antigen-specific suppressor factors (10). Unfortunately, their hybrids rapidly lost factor production.

Inhalt
Lectin-Dependent Cytolytic and Cytolymic T Helper Clones and Hybridomas.- Cytotoxic T Cell Hybridomas: Generation and Characterization.- Definition of Function-Related Isotypic Markers on T Cells.- An Antigen-Specific Suppressor T Cell Factor Controlled by Two Genes in the Immunglobulin Heavy Chain Linkage Group and in the I-J Subregion of the H-2 Complex.- Structural and Functional Studies on Antigen-Specific Suppressor Factors from T Cells and T Cell Hybrids.- Purification and Biochemical Analysis of Antigen-Specific Suppressor Factors Isolated from T-Cell Hybridomas.- Dissection of a Suppressor Cell Cascade.- 4-Hydroxy-3-nitro-phenylacetyl (NP)-Specific T Cell Hybridomas.- Regulation of the IgE Response by IgE Class-Specific Suppressor T Hybridomas.- Establishment of Functional, Antigen-Specific T Cell Lines by RadLV-Induced Transformation of Murine T Lymphocytes.- H-2-Restricted Helper Hybridomas: One Locus or Two Control Dual Specificity?.- T Cell Hybridomas Producing Antigen-Specific Factors Express Heavy-Chain Variable-Region Determinants.- Cytochrome c Specific T Cell Hybrid.- The Effect of Antigen Presentation on the Fine Specificity of Anti-Cytochrome c T Cell Hybridomas.- Analysis of the Anti-Self + TNP Immune Response: T Cell Lines, Clones and Hybridomas.- Functional Characteristics of T Cell Hybridomas Obtained by Fusion of TCGF-Dependent Helper T Cell Clones with BW5147.- A Stable TCGF-Producing T Cell Hybridoma and its Thioguanine-Resistant Variant Suitable as a Tool for the Construction of New Functional T Hybridomas.- Influenza Virus-Specific Murine T Cell Hybridomas Which Recognize Virus Hemagglutinin in Conjunction with H-2d and Display Helper Functions for B Cells.- A Panreactive T Cell Line and T Cell Hybridoma: Their Function in Helping B Cells.- A Panreactive T Cell Hybridoma Which Produces TCGF Constitutively.- Production of Antigen-Nonspecific Immunoregulatory Lymphokines by T Cell Hybridomas.- Human T Cell Hybridomas with Tetanus-Toxoid-Specific Helper Activity.- Functional Analysis of I1-2 Produced by T-Cell Hybridomas: I1-2 Promotes T-Cell Growth But Does Not Mediate T-Cell or B-Cell Maturation and Differentiation.- Molecular Characterization of Interleukin 2 Produced from Tumor Cell Lines and T Cell Hybridomas.- The Use of T Cell Hybridomas in the Biochemical and Biological Characterization of Multiple Regulatory Factors Produced by T Cells.- Different Factors Active in Lymphoid and Hematopoietic Proliferation Produced by Single Clones of Helper T Cell Hybridomas.- Lymphotoxin and Immune (?) Interferon Production by T Cell Lines and Hybrids.- Antigen Specificity of Continuous T Cell Lines.- List of Contributors.- Indexed in Current Contents.