Immunological biomarkers: catalysts for translational advances in autoimmune diabetes

In a recent workshop organized by the JDRF focused on the 'Identification and Utilization of Robust Biomarkers in Type1 Diabetes', leaders in the field of type 1 diabetes (T1D)/autoimmunity and assay technology came together from academia, government and industry to assess the current state of the field, evaluate available resources/technologies and identify gaps that need to be filled for moving the field of T1D research forward. The highlights of this workshop are discussed in this paper, as well as the proposal for a larger, planned consortium effort, incorporating a JDRF Biomarker Core, to foster collaboration and accelerate progress in this critically needed area of T1D research.

Biologic activity of an idiotype-bearing suppressor T cell factor produced by a long-term T cell hybridoma

Biologic activities and immunochemical characteristics of an azobenzenearsonate- (ABA)specific suppressor T cell factor produced by a longterm T cell hybridoma, F12, were studied. In vivo administration of F12 culture supernatant resulted in the suppression of ABA-specific delayed-type hypersensitivity (DTH) responses and the inhibition of priming for ABA-specific cytotoxic T lymphocyte responses. Moreover, F12 induced a second set of suppressor cells that act in the efferent phase of DTH. The active material in the F12 culture supernatant expressed major cross-reactive idiotypic (CRI) determinants of anti-ABA antibodies of A/J mice and I-J subregion-coded specificities but not express determinants of immunoglobulin constant regions. These results demonstrated that F12 is a functioning hybrid cell line of the first-order suppressor T cell subset.

Biologic activity of an idiotype-bearing suppressor T cell factor produced by a long-term T cell hybridoma

Biologic activities and immunochemical characteristics of an azobenzenearsonate- (ABA)specific suppressor T cell factor produced by a longterm T cell hybridoma, F12, were studied. In vivo administration of F12 culture supernatant resulted in the suppression of ABA-specific delayed-type hypersensitivity (DTH) responses and the inhibition of priming for ABA-specific cytotoxic T lymphocyte responses. Moreover, F12 induced a second set of suppressor cells that act in the efferent phase of DTH. The active material in the F12 culture supernatant expressed major cross-reactive idiotypic (CRI) determinants of anti-ABA antibodies of A/J mice and I-J subregion-coded specificities but not express determinants of immunoglobulin constant regions. These results demonstrated that F12 is a functioning hybrid cell line of the first-order suppressor T cell subset.

Tumor-Associated Blocking Factors: Isolation from Sera of Tumor-Bearing Mice

An isolation and partial purification of tumor-associated blocking factors from the sera of tumor-bearing mice is described. Columns for affinity chromatography were prepared by coupling syngeneic tumor-immune antibodies to Sepharose 4B. Passage of serum through such immunoadsorbent columns removed all blocking activity from tumorbearers' sera; subsequent elution of the absorbent with 3 M NaSCN recovered the activity. The blocking material was further purified on Sephadex G-200. The data provide evidence for the presence of antigen in tumor-associated blocking factors and are compatible with the hypothesis that blocking factors often consist of antigen and antibodies in the form of immune complexes.

Tumor-associated blocking factors: isolation from sera of tumor-bearing mice

An isolation and partial purifications of tumor-associated blocking factors from the sera of tumor-bearing mice is described. Columns for affinity chromatography were prepared by coupling syngeneic tumor-immune antibodies to Sepharose 4B. Passage of serum through such immunoadsorbent columns removed all blocking activity from tumor-bearers' sera; subsequent elution of the absorbent with 3 M NaSCN recovered the activity. The blocking material was further purified on Sephadex G-200. The data provide evidence for the presence of antigen in tumor-associated blocking factors and are compatible with the hypothesis that blocking factors often consist of antigen and antibodies in the form of immune complexes.