       Document 0079
 DOCN  M9470079
 TI    Coordinate defects in human histocompatibility leukocyte antigen class
       II expression and antigen presentation in bare lymphocyte syndrome.
 DT    9409
 AU    Kovats S; Drover S; Marshall WH; Freed D; Whiteley PE; Nepom GT; Blum
       JS; Immunology and Diabetes Programs, Virginia Mason Research Center,;
       Seattle, Washington 98101.
 SO    J Exp Med. 1994 Jun 1;179(6):2017-22. Unique Identifier : AIDSLINE
       MED/94253742
 AB    The human immunodeficiency, type II bare lymphocyte syndrome (BLS), has
       been attributed to a defect in the transcription of class II
       histocompatibility genes. Immunocompetence, as assessed by functional
       exogenous antigen presentation, was not restored in immortalized B
       cells, derived from a BLS patient, after transfection with HLA-DR class
       II structural genes. Incubation of protein antigens, as well as
       infectious virus, with DR-transfected BLS cells failed to induce
       activation of antigen-specific helper T lymphocytes. Peptide antigens
       were presented by class II molecules displayed on BLS cells, although
       the conformation of these class II proteins was altered as indicated by
       epitope mapping. This defect in antigen presentation was independent of
       the specific class II DR allele transfected into BLS cells. Genetic
       complementation analysis has been used with BLS cells to demonstrate
       that the defect in class II gene transcription is linked to the absence
       of a trans-acting factor. Similarly, functional class II dimers were
       restored after in vitro fusion of cells derived from two distinct BLS
       complementation groups, implying that specific transcriptional control
       elements are shared by a gene critical for antigen presentation and
       genes encoding HLA class II antigens. Thus, two important functionally
       linked pathways of class II molecules, structural gene expression and
       antigen presentation, share a common regulatory pathway defective in
       BLS.
 DE    Alleles  Amino Acid Sequence  Cell Fusion  Cell Line  Clone Cells  *Gene
       Expression  *Genes, MHC Class II  Genes, Structural  Genetic
       Complementation Test  Human  HLA-D Antigens/*BIOSYNTHESIS  Immunologic
       Deficiency Syndromes/GENETICS/*IMMUNOLOGY  Molecular Sequence Data
       Oligopeptides/CHEMICAL SYNTHESIS/IMMUNOLOGY  Support, Non-U.S. Gov't
       Support, U.S. Gov't, P.H.S.  T-Lymphocytes/*IMMUNOLOGY  Transcription,
       Genetic  Transfection  JOURNAL ARTICLE

       SOURCE: National Library of Medicine.  NOTICE: This material may be
       protected by Copyright Law (Title 17, U.S.Code).

