Biomaterial Database

The requirement for DM in class II-restricted antigen presentation and SDS-stable dimer formation is allele and species dependent. 1995

C C Stebbins, and G E Loss, and C G Elias, and A Chervonsky, and A J Sant

Department of Pathology, University of Chicago, Illinois 60637.

Recently several cell lines have been identified with mutations in a major histocompatibility complex (MHC)-linked protein that lead to defects in class II-restricted antigen presentation and a defect in the formation of class II SDS-stable dimers. The defect in these cells has recently been shown to result from the inability to express the MHC-encoded nonclassical class II molecule called DM. To further examine the role of DM in class II-restricted antigen presentation, we asked if this defect would equally affect different allelic and species variants of class II molecules. To investigate this, we transfected the parent cell lines T1 and 8.1.6 and their respective antigen presentation mutants T2 and 9.5.3 with the genes encoding I-Ad and examined the derived transfectants for their ability to present antigen, the conformation of I-Ad at the cell surface, association of I-Ad with invariant chain (Ii), and the ability to form I-Ad SDS-stable dimers. The lack of functional DM expression did not affect any of the anti-I-Ad monoclonal antibody (mAb) epitopes tested or the ability of I-Ad to associate and dissociate with Ii. Surprisingly, these studies also revealed that the antigen presentation defect observed for DR in the 9.5.3 cells did not compromise I-Ad-restricted antigen presentation. In addition, we found that the level of SDS-stable dimer formation did not correlate with antigen presentation capacity for I-Ad and that the amount of SDS-stable I-Ad dimer depends on the cellular context in which the class II molecule is expressed. Our results suggest that the ability to form SDS-stable dimer is not strictly correlated with class II-restricted antigen presentation. Finally, when two allelic forms of murine class II molecules were compared in the defective T2 cell line, it was found that I-Ak but not I-Ad forms SDS-stable dimers equivalent to that seen in the parental cell lines. Overall, our results suggest that DM may modulate rather than play a requisite role in I-Ad-restricted antigen presentation and SDS-stable dimer formation and that dependency on DM may be allele or species specific.

UI	MeSH Term	Description	Entries
D010455	Peptides	Members of the class of compounds composed of AMINO ACIDS joined together by peptide bonds between adjacent amino acids into linear, branched or cyclical structures. OLIGOPEPTIDES are composed of approximately 2-12 amino acids. Polypeptides are composed of approximately 13 or more amino acids. PROTEINS are considered to be larger versions of peptides that can form into complex structures such as ENZYMES and RECEPTORS.	Peptide,Polypeptide,Polypeptides
D004640	Emetine	The principal alkaloid of ipecac, from the ground roots of Uragoga (or Cephaelis) ipecacuanha or U. acuminata, of the Rubiaceae. It is used as an amebicide in many different preparations and may cause serious cardiac, hepatic, or renal damage and violent diarrhea and vomiting. Emetine inhibits protein synthesis in EUKARYOTIC CELLS but not PROKARYOTIC CELLS.	Ipecine,Methylcephaeline,Emetine Dihydrochloride,Emetine Hydrochloride,Dihydrochloride, Emetine,Hydrochloride, Emetine
D006681	HLA-D Antigens	Human immune-response or Class II antigens found mainly, but not exclusively, on B-lymphocytes and produced from genes of the HLA-D locus. They are extremely polymorphic families of glycopeptides, each consisting of two chains, alpha and beta. This group of antigens includes the -DR, -DQ and -DP designations, of which HLA-DR is most studied; some of these glycoproteins are associated with certain diseases, possibly of immune etiology.	Antigens, HLA-D,Class II Human Antigens,HLA-Dw Antigens,Human Class II Antigens,Ia-Like Antigens, Human,Immune Response-Associated Antigens, Human,Immune-Associated Antigens, Human,Immune-Response Antigens, Human,HLA-D,HLA-Dw,Immune Response Associated Antigens, Human,Antigens, HLA D,Antigens, HLA-Dw,Antigens, Human Ia-Like,Antigens, Human Immune-Associated,Antigens, Human Immune-Response,HLA D Antigens,HLA Dw Antigens,Human Ia-Like Antigens,Human Immune-Associated Antigens,Human Immune-Response Antigens,Ia Like Antigens, Human,Immune Associated Antigens, Human,Immune Response Antigens, Human
D006684	HLA-DR Antigens	A subclass of HLA-D antigens that consist of alpha and beta chains. The inheritance of HLA-DR antigens differs from that of the HLA-DQ ANTIGENS and HLA-DP ANTIGENS.	HLA-DR,Antigens, HLA-DR,HLA DR Antigens
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D006825	Hybridomas	Cells artificially created by fusion of activated lymphocytes with neoplastic cells. The resulting hybrid cells are cloned and produce pure MONOCLONAL ANTIBODIES or T-cell products, identical to those produced by the immunologically competent parent cell.	Hybridoma
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D000938	Antigen-Presenting Cells	A heterogeneous group of immunocompetent cells that mediate the cellular immune response by processing and presenting antigens to the T-cells. Traditional antigen-presenting cells include MACROPHAGES; DENDRITIC CELLS; LANGERHANS CELLS; and B-LYMPHOCYTES. FOLLICULAR DENDRITIC CELLS are not traditional antigen-presenting cells, but because they hold antigen on their cell surface in the form of IMMUNE COMPLEXES for B-cell recognition they are considered so by some authors.	Accessory Cells, Immunologic,Antigen-Presenting Cell,Immunologic Accessory Cells,Accessory Cell, Immunologic,Cell, Immunologic Accessory,Cells, Immunologic Accessory,Immunologic Accessory Cell,Antigen Presenting Cell,Antigen Presenting Cells,Cell, Antigen-Presenting,Cells, Antigen-Presenting
D000944	Antigens, Differentiation, B-Lymphocyte	Membrane antigens associated with maturation stages of B-lymphocytes, often expressed in tumors of B-cell origin.	Antigens, Differentiation, B-Cell,B-Cell Differentiation Antigens,B-Lymphocyte Differentiation Antigens,Blast-2 Antigen, B-Cell,Differentiation Antigens, B-Cell,Differentiation Antigens, B-Lymphocyte,Leu Antigens, B-Lymphocyte,Plasma Cell Antigens PC-1,Antigens, Differentiation, B Lymphocyte,Antigens, Plasma Cell, PC-1,B-Cell Blast-2 Antigen,Antigen, B-Cell Blast-2,Antigens, B-Cell Differentiation,Antigens, B-Lymphocyte Differentiation,Antigens, B-Lymphocyte Leu,B Cell Blast 2 Antigen,B Cell Differentiation Antigens,B Lymphocyte Differentiation Antigens,B-Lymphocyte Leu Antigens,Blast 2 Antigen, B Cell,Differentiation Antigens, B Cell,Differentiation Antigens, B Lymphocyte,Leu Antigens, B Lymphocyte,Plasma Cell Antigens PC 1
D000949	Histocompatibility Antigens Class II	Large, transmembrane, non-covalently linked glycoproteins (alpha and beta). Both chains can be polymorphic although there is more structural variation in the beta chains. The class II antigens in humans are called HLA-D ANTIGENS and are coded by a gene on chromosome 6. In mice, two genes named IA and IE on chromosome 17 code for the H-2 antigens. The antigens are found on B-lymphocytes, macrophages, epidermal cells, and sperm and are thought to mediate the competence of and cellular cooperation in the immune response. The term IA antigens used to refer only to the proteins encoded by the IA genes in the mouse, but is now used as a generic term for any class II histocompatibility antigen.	Antigens, Immune Response,Class II Antigens,Class II Histocompatibility Antigen,Class II Major Histocompatibility Antigen,Ia Antigens,Ia-Like Antigen,Ia-Like Antigens,Immune Response Antigens,Immune-Associated Antigens,Immune-Response-Associated Antigens,MHC Class II Molecule,MHC II Peptide,Class II Antigen,Class II Histocompatibility Antigens,Class II MHC Proteins,Class II Major Histocompatibility Antigens,Class II Major Histocompatibility Molecules,I-A Antigen,I-A-Antigen,IA Antigen,MHC Class II Molecules,MHC II Peptides,MHC-II Molecules,Antigen, Class II,Antigen, I-A,Antigen, IA,Antigen, Ia-Like,Antigens, Class II,Antigens, Ia,Antigens, Ia-Like,Antigens, Immune-Associated,Antigens, Immune-Response-Associated,I A Antigen,II Peptide, MHC,Ia Like Antigen,Ia Like Antigens,Immune Associated Antigens,Immune Response Associated Antigens,MHC II Molecules,Molecules, MHC-II,Peptide, MHC II,Peptides, MHC II