Cell surface properties of HLA antigens on Epstein-Barr virus-transformed cell lines.

Abstract

A number of monoclonal antibodies have been used to investigate the distributions and rates of lateral motion. of the HLA-A,B, and -DR antigens on several Epstein-Barr virustransformed B-cell lines. The lateral diffusion coefficients (D) of fluorescein conjugates of.the monoclonal antibodies bound to the cell surface were determined by fluorescence recovery after pattern photobleaching. Ds of HLA-A and -B were.found to be comparable and of the order of 1009 to 10-1o cm2/sec for each of the seven monoclonal antibodies and four cell lines examined. The HLA antigens. appear to be monomeric on the cell surface based on experiments using mixtures of arsanilic acid-conjugated and fluorescein-conjugated antibodies. Four monoclonal antibodies against DR antigens were examined. Two ofthese, Genox3.53 and L243, labeled the cell surface uniformly and gave Ds comparable to those obtained for the HILA-A and -B antigens. The other two, DA2 and 2.06, rapidly patched on the cell surface and were immobile. The DA2, L243, and Genox 3.53 antibodies bound outside ofthe caps formed with the arsanilic acid-conjugated 2.06 antibody and a second-step rhodamine-conjugated rabbit anti-arsanilate antibody. This is consistent with recent biochemical evidence that there are multiple distinct antigens coded for by the HLA-DR region.The major histocompatability complex codes for a series ofpolymorphic cell surface antigens important for the control of cellular interactions in immunity (1-6). Two different types of glycoprotein complexes provide the molecular basis for the HLA-

Dendritic cell/lymphocyte clustering: Morphologic analysis by transmission electron microscopy and distribution of gold‐labeled MHC class II antigens by high‐resolution scanning electron microscopy

“…Previous studies regarding MHC Ag (Class I) mobility and distribution indicate that these molecules exist as freely rotating monomers, without appreciable clustering within the surface membrane (Edidin and Wei, 1982;Smith et al, 1982;Damjanovich et al, 1983). These studies also noted that lateral mobility of MHC Ags is restricted, presumably due to interactions with underlying cytoskeletal components.…”

Human Cytomegalovirus Alters Localization of MHC Class II and Dendrite Morphology in Mature Langerhans Cells

“…For three-color analysis, cells were surface stained with combinations of anti-CD83 PE and anti-DR PerCP, or anti-CD83 allophycocyanin and anti-DR PE mAbs, followed by intracellular anti-IE1/IE2 FITC (clone 8B1.2; Chemicon International). Ab to CD83 (PE; clone HB15e), HLA-DR (PerCP, clone L243) (26), and appropriate isotype controls were obtained from BD Biosciences. Ab against HLA-DR (FITC or PE, clone TU36), total HLA class I (FITC or PE, clone TU149), CD83 (allophycocyanin, clone HB15e), and respective isotype controls were purchased from Caltag Laboratories.…”

Preclinical studies on targeted delivery of multiple IFNα2b to HLA-DR in diverse hematologic cancers

“…9 IMMU-114 (or hL243␥4p) is a humanized IgG 4 version of L243, a mouse anti-HLA-DR mAb, which was engineered to prevent the formation of half-IgG molecules associated with the IgG 4 isotype. 10 IMMU-114 has direct cytotoxicity on various types of hematopoietic cell lines in vitro and in vivo; as an IgG 4 variant, its effector functions, particularly complement-dependent cytotoxicity (CDC), are minimized. 11 We previously used the modular Dock-and-Lock (DNL) method 12,13 to generate a novel immunocytokine, named 20-2b-2b (formerly 20-2b), which comprises 4 IFN␣2b groups tethered to veltuzumab (humanized anti-CD20 mAb), and showed potent in vitro and in vivo activity in human NHL xenograft models.…”