myelin-basic-protein and Fibrosarcoma

Immunization with heat-shock protein (HSP) gp96 elicits protective immunity to the cancer or virus-infected cells from which it is derived. Low doses of gp96 generate immunity, while doses 10 times the immunizing dose do not. We show here that injection of high doses of gp96 generates CD4(+) T cells that down-regulate a variety of ongoing immune responses. Immunization with high doses of gp96 prevents myelin basic protein- or proteolipid protein-induced autoimmune encephalomyelitis in SJL mice and the onset of diabetes in non-obese diabetic mice. The suppression of immune response can be adoptively transferred with CD4(+) cells and does not partition with the CD25 phenotype. The immunomodulatory properties of gp96 (and possibly other HSP) may be used for antigen-specific activation or suppression of cellular immune responses. The latter may form the basis for novel immunotherapies for autoimmune diseases.

Topics: Adoptive Transfer; Animals; Antigens, Neoplasm; CD4-Positive T-Lymphocytes; CD8-Positive T-Lymphocytes; Cell Transplantation; Diabetes Mellitus, Type 1; Encephalomyelitis, Autoimmune, Experimental; Female; Fibrosarcoma; Glycosuria; Immune Tolerance; Immunohistochemistry; Immunologic Factors; Immunotherapy, Active; Insulin; Lipopolysaccharides; Lymphocyte Subsets; Mice; Mice, Inbred BALB C; Mice, Inbred NOD; Myelin Basic Protein; Myelin Proteolipid Protein; Pancreas; Paralysis; Peptide Fragments; Receptors, Interleukin-2; Spleen; Time Factors; Tumor Cells, Cultured; Vaccination

The collective expression of five antigens produced in immature or mature myelin-producing glia was evaluated in nerve sheath tumors and spindle cell sarcomas with histologic features of schwannomas. Myelin-associated glycoprotein (Leu-7), myelin basic-protein (MBP), S100-protein, and, in most cases, glial-fibrillary acidic-protein (GFAP) and HLA-DR/Ia (LN3) immunoreactivity were evaluated immunohistochemically using commercially available antibodies on 53 benign nerve sheath tumors and 12 sarcomas. Leu-7 immunoreactivity was detected by a monoclonal antibody in 12 of 16 schwannomas, 12 of 20 neurofibromas, and 17 of 17 traumatic neuromas. No Leu-7 positivity was seen in the sarcomas. Distinct heavy MBP immunoreactivity, assessed using polyclonal antibodies, was identified only in all 17 traumatic neuromas. Extensive S100-protein positivity was seen in 15 of 16 schwannomas, 17 of 20 neurofibromas, and 17 of 17 traumatic neuromas. Extensive LN3 immunoreactivity was seen in Schwann cells of 50% of the nerve sheath tumors analyzed; however, it was also present in associated interdigitating reticulum cells; GFAP immunoreactivity was not detected. These data suggest that Leu-7 is an important marker of Schwann cell neoplasms, although it is not superior to S100 protein. Moreover, combined immunohistochemical evaluation of potential Schwann cell markers including Leu-7, MBP, GFAP, and LN3 using commercially available antibodies offers no advantage over analysis of S100-protein immunoreactivity alone.

Topics: Antigens, Differentiation, T-Lymphocyte; Antigens, Neoplasm; Fibrosarcoma; Glial Fibrillary Acidic Protein; Histocompatibility Antigens Class II; Humans; Immunohistochemistry; Leiomyosarcoma; Myelin Basic Protein; Myelin Proteins; Myelin Sheath; Myelin-Associated Glycoprotein; Neoplasm Proteins; Nervous System Neoplasms; Neurilemmoma; Neurofibroma; S100 Proteins; Sarcoma; Schwann Cells

Spleen cells (SC) from tumor-bearing mice and mice immunized with porcine myelin basic protein (MBP) reacted in vitro in E-rosette augmentation assays with MBP and certain of its constituent peptides. Peptides 1-115, 43-169, 64-83, 113-121, and 153-161 reacted significantly with both types of SC, while peptide 1-19 reacted only with SC from MBP-immunized mice. The phenomenon of specific inhibition of peptide reactivity by a moderate excess of a related protein was used to identify peptides as accessible epitopes of that protein. Peptide 113-121 was specifically inhibited by excess MBP when reacted with both types of SC, whereas peptide 64-83 was inhibited by excess MBP only when reacted with SC from MBP-immunized mice. These reactions suggest that the immunizing antigen in tumor-bearing mice is related to MBP but differs in epitopes associated with peptides 1-19 and 64-83.

Topics: Amino Acid Sequence; Animals; Dose-Response Relationship, Immunologic; Fibrosarcoma; Guinea Pigs; Immunity, Cellular; Immunization; Mice; Mice, Inbred CBA; Myelin Basic Protein; Neoplasm Transplantation; Neoplasms, Experimental; Rats; Rats, Inbred Lew; Rosette Formation; Spleen

Suppressor factors in the serum of CBA mice bearing transplanted methylcholanthrene-induced tumours suppressed the leukocyte adherence inhibition reaction between tumour-sensitized peritoneal cells and a sequenced antigen, myelin basic protein (MBP). Chromatography on Sephacryl S-200 columns demonstrated suppressive activity in low molecular weight fractions (40-50 kDa) derived from whole serum. The factors were absorbed from serum by MBP, but not by lysozyme, coupled to Sepharose gel. Cleavage with sodium dodecyl sulphate (SDS) and absorption with either MBP or anti-I-J antibody on Sepharose gels yielded inactive supernatants that regained suppressive activity when combined. Elution of these gels with acidic buffer yielded eluates that were inactive alone but suppressive when combined. These results indicate that the tumour-related suppressor factors consist of two chains separable by detergent action; one chain is antigen (MBP)-binding and the other contains an I-J determinant.

Topics: Animals; Fibrosarcoma; Histocompatibility Antigens Class II; Isoantibodies; Leukocyte Adherence Inhibition Test; Lymphokines; Mice; Mice, Inbred CBA; Myelin Basic Protein; Peritoneal Cavity; Suppressor Factors, Immunologic

Mice bearing a methylcholanthrene-induced tumour were tested for their cell mediated reactivity to the experimental allergic encephalomyelitis (EAE) peptide of human myelin basic protein (MBP) in the leucocyte adherence inhibition (LAI) test. Tested over a range of peptide concentrations, peritoneal cells (PC) from tumour-bearing mice exhibited optimal adherence inhibition at 640 ng/ml; PC from normal and parasite-infected mice were unreactive. The EAE peptide also stimulated PC from tumour-bearing mice in the E-rosette augmentation (ERA) test and in the macrophage migration inhibition (MMI) test. MMI appeared to be the most sensitive assay, in that significant reaction at peptide concentrations well below those giving significant LAI and ERA. LAI reactivity to the peptide was detected 5 days after tumour transplantation, and continued to be detectable even with very large tumours. In vitro assays were confirmed by demonstration of EAE peptide recognition in vivo, in tumour-bearing and tumour-excised mice, using the delayed-type hypersensitivity reaction. The present experiments demonstrate an antigenic determinant in murine tumours, similar to the well-characterized EAE peptide of human MBP, and establish an animal model for study and characterization of common tumour-associated antigens.

Topics: Animals; Dose-Response Relationship, Immunologic; Encephalomyelitis, Autoimmune, Experimental; Fibrosarcoma; Hypersensitivity, Delayed; Immunity, Cellular; Kinetics; Leukocyte Adherence Inhibition Test; Macrophages; Mice; Mice, Inbred CBA; Myelin Basic Protein; Sarcoma, Experimental