Immuno-electron-microscopic localization of enkephalin in the secretory granules of C cells in the chicken ultimobranchial glands

Interstitial cells in the pineal gland of the rat were characterized immunocytochemically using the monoclonal antibodies MRC OX-42 and ED1 for macrophages/microglia, and MRC OX-6, which recognizes major histocompatibility complex (MHC) class II antigen. A polyclonal antibody against GFAP was used to identify astrocytes. Cells immunopositive for OX-42 and/or ED1 were distributed throughout the gland; they extended processes primarily along the perivascular spaces and occasionally within the parenchyma of the gland. Ultrastructurally, these OX-42-positive cells were characterized by a nucleus with sparse heterochromatin and cytoplasmic vacuoles/lysosomes. Cells expressing MHC class II antigen had a distribution and morphology similar to OX-42-immunopositive cells, suggesting that pineal macrophages/microglia play a role as antigen-presenting cells. GFAP-positive astrocytes were concentrated at the proximal end of the pineal where the pineal stalk enters the gland. The occurrence of antigenpresenting cells in the circumventricular neuroendocrine gland has important functional implications as these cells may be mediators of neuroimmunomodulatory mechanisms, and involved in certain disease states such as autoimmune pinealitis.     

Vicia villosa B4 lectin is the second anti-Tn lectin shown to react better with blood group N than M antigen

Earlier studies showed thatMoluccella laevis lectin, which has anti-Tn specificity, reacts more strongly with native or desialylated blood group N glycophorin A than with the respective glycophorins of blood group M. We now present results indicating thatVicia villosa B4 anti-Tn lectin, which does not show detectable reaction with untreated glycophorins or erythrocytes, reacts better with desialylated blood group N antigen than with asialo M antigen. This was demonstrated by three assays: (1) agglutination of asialoerythrocytes; (2) binding of biotinylated lectin to asialoerythrocytes immobilized on ELISA plates; and (3) inhibition of lectin binding to asialo-agalactoglycophorin with asialoglycophorins M and N. These results supply further support for the conclusion that glycophorin of blood group N has more GalNAc residues unsubstituted with Gal (Tn receptors) than glycophorin of blood group M.Abbreviations GPA glycophorin A - GPA-M and GPA-N GPA from OM and ON erythrocytes, respectively - MLL Moluccella laevis lectin - PBS 0.02m phosphate buffer/0.15m NaCl, pH 7.4 - PNA peanut agglutinin - RBC erythrocytes - TBS 0.05m Tris buffer/0.15m NaCl, pH 7.4 - TBS-T TBS containing 0.02% Tween 20 - VVL Vicia villosa B4 lectin     

Expression and characterization of a parasite-specific antigen on macrophages after infection withLeishmania donovani

A rabbit polyclonal antibody to crude soluble antigen ofLeishmania donovani promastigotes recognized a determinant expressed on the surface membrane of mouse peritoneal macrophages and human monocyte derived macrophages infectedin vitro. The determinant was recognized on infected macrophage surface only when F (ab)₂ fragments of anti-leishmanial antiserum was employed in immunofluorescence. F(ab)₂ fragments of human patient sera also could recognize the determinant. The expression of this antigen was not stage-specific for the parasite. Immunochemical analyses revealed this antigen to be of 51 kDa protein. Specific leaching of membrane proteins by trypsin showed three bands of expressed antigens of 26, 11 and 10 kDa, which in all likelihood might be arising from the 51 kDa antigen. The antigen was not expressed until 12 h of post infection, reached a maximum level at 24 h and thereafter attained a steady state level as studied upto 96 h of post infection. This typc of antigen might have a great potential in immunodiagnostics and site-specific drug targeting.     

乳腺癌组织中ER、PR和CEA相关性研究

应用免疫组化技术亲和组化法和ＡＢＣ法,检测了１０６例乳腺癌组织中ＥＲ、ＰＲ和ＣＥＡ水平。其阳性率依次为８３％、８１．１％和８８．７％。其中７９．２％的乳腺癌ＥＲ和ＰＲ表达一致。在９８例ＥＲ和／或ＰＲ阳性乳腺癌中有９２例（９３．９％）呈ＣＥＡ阳性,８例ＥＲ和ＰＲ阴性乳腺癌中６例（７５％）为ＣＥＡ阴性,８９％乳腺癌ＣＥＡ与ＥＲ和ＰＲ表达一致。在癌的分级表达中,随着癌的组织学分级增高ＣＥＡ阳性率增高,而ＥＲ和ＰＲ阳性率减低。结果表明,乳腺癌ＥＲ、ＰＲ和ＣｈＡ表达可反映肿瘤的不同生物学特征。同时检测三者对选择内分泌治疗及判断预后更有意义。     

Further studies of the therapeutic effectsof murine melanoma-specific monoclonal antibodies

The results presented here further characterize four murine monoclonal antibodies (mAb) that recognize melanoma-specific antigens (9B6, T97, 2-3-1 and 2-3-3). These melanoma-specific mAbs are of the IgG_2b isotype and are significantly therapeutic when administered systemically against established pulmonary melanoma metastases. Here we show a consistent and significantly inhibition of the growth of melanoma lung metastases by all four mAbs and the existence of a time ‘window’ at days 5–8 after tumor inoculation for optimal therapy. Since these mAbs were found not to be cytotoxic or cytolytic in vitro, we looked for host immune response regulation as being responsible for the therapeutic effects. Natural killer (NK) cells were implication as one arm of the host immune system involved in this response since depletion of NK cells in vivo by αasialoGM1 or αNK1.1 antibodies partially abrogated the inhibitory effect of the mAbs. The observed antimetastatic effects could also be partially abrogated using antibodies directed against the T-cell subset surface markers, CD4⁺ and CD8⁺. Intramuscular melanoma tumor growth was also found to be suppressed by mAb 2-3-1, but only if administered in the area of tumor growth and only if multiple inoculations are administered over a 13-day period. The beneficial effect of mAb antimetastatic therapy was found to be useful against several syngeneic melanomas, including JB/MS, B16 and several sublines of the B16 F10 melanoma.     

Isolation of an adhesin from Staphylococcus aureus that binds Lewis blood group antigen and its relevance to sudden infant death syndrome

Abstract A 67 kDa protein was isolated from cell membrane preparations of Staphylococcus aureus (NCTC 10655) by affinity adsorption with synthetic Lewis antigen conjugated to Synsorb beads. Pre-treatment of buccal epithelial cells expressing Lewis with the purified protein reduced binding of the staphylococcal strain to a greater extent than the material not bound to the Synsorb beads. The significance of this work is discussed with reference to expression of Lewis antigen in infants and the proposed role of toxigenic strains of staphylococci in some cases of sudden infant death syndrome.     

Crystallization and preliminary X-ray crystallographic analysis of the 38-kDa immunodominant antigen of Mycobacterium tuberculosis.

The 38-kDa lipoprotein is one of the most potent cell surface immunogens of Mycobacterium tuberculosis in antibody-and T cell-mediated reactions. Using a pure recombinant form of the protein, we have recently shown that it binds phosphate much like that of the phosphate-binding protein (M(r) = 34.4 kDa) that is localized in the periplasm of Escherichia coli and is involved as an initial receptor for active transport of phosphate. The purified 38-kDa protein has been crystallized in 2 forms that are suitable for high-resolution structural analyses. One form belongs to the monoclinic space group P2(1) with unit cell dimensions of a = 67.42 A, b = 113.38 A, c = 42.68 A, and beta = 108.53 degrees. The other is of orthorhombic space group P2(1)2(1)2 with a = 125.46 A, b = 72.27 A, and c = 73.43 A. Both crystal forms diffract to about 2 A resolution on a fine focus rotating anode.     

微波免疫组织化学技术在宫颈癌涂片快速诊断中的应用

本文应用微波免疫组化ＡＢＣ技术检测了６７例宫颈涂片细胞中ＥＭＡ的分布。结果,Ｉ～Ｖ级宫颈涂片ＥＭＡ阳性率分别为３０％（３／１０）、５０％（５／１０）、７０％（７／１０）、９３．７％（１５／１６）和９５．２％（２０／２１）。Ⅰ、Ⅱ级与Ⅲ级,Ⅲ级与Ⅳ、Ⅴ级ＥＭＡ阳性率均有显著差异性（Ｐ＜０．０５）。结果提示：ＥＭＡ可作为宫颈涂片细胞的分化标志,有助于良恶性细胞的鉴别。同时对形态学不够恶性而ＥＭＡ呈强阳性者,有潜在恶变的物质基础。在抗体稀释度相同时,微波免疫组化较常规免疫组化具有特异性染色深。背景浅,反应时间显著缩短等特点。     

夏氏疟原虫入侵时小鼠红细胞膜唾液酸糖蛋白的改变

夏氏疟原虫入侵时小鼠红细胞膜唾液酸糖蛋白的改变刘俊凡,卢义钦（湖南医科大学生化教研室,长沙４１Ｏ０７８〕ＲｏｎａｌｄＬ．ＮｏｇｅｌＯｌｇａＯ．Ｂｌｕｍｅｎｆｅｌｄ（爱因斯坦医学院内科血液学研究室和生化学系,美国纽约１０４６１）关键词夏氏疟原虫;红细胞...