title: H-2D antigens released by thymocytes and cell adhesion.
abstract: The identity and complete purification of mouse Thymocyte Interaction Modulation Factor (T IMF) is described. Use of silver-stained PAGE methods shows that previous methods of purification yield preparations containing two protein or glycoprotein bands. T IMF activity from H-2k mice can be bound to 15.5.5 monoclonal antibody columns (anti H-2 Dk) but not to 11.4.1 columns (anti H-2 Kk). The activity can be recovered from 15.5.5 columns and runs on PAGE aa a single band at approximately 34,000 Daltons. This evidence together with previous evidence relating the activity to H-2D locus argues that T IMF is a soluble H-2 D antigen fragment equivalent to a papainized H-2 fragment. Additional evidence is presented on an improved method of assay of T IMF activity, on its inactivation by enzymes and serine-esterase inhibitors and of its effect on syngeneic leucocytes and macrophages. It is shown that T IMF is not appreciably toxic cells.
mesh_terms: D000818:Animals; D002448:Cell Adhesion / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D006023:Glycoproteins / Q000276:immunology* / Q000302:isolation & purification / Q000494:pharmacology; D006183:H-2 Antigens / Q000302:isolation & purification*; D066298:In Vitro Techniques; D008222:Lymphokines / Q000302:isolation & purification*; D051379:Mice; D008808:Mice, Inbred CBA; D008970:Molecular Weight; D013601:T-Lymphocytes / Q000276:immunology*
chemical_list: D006023:Glycoproteins; D006183:H-2 Antigens; D008222:Lymphokines; C031650:thymocyte interaction modulation factor