小儿糖尿病血胰岛细胞抗体与胰岛素自身抗体

报道并分析20例小儿糖尿病患儿的临床资料及血胰岛细胞抗体(ICA)及胰岛素自身抗体(IAA)的测定资料。在20例患儿中,临床表现多不典型。在酮症酸中毒的治疗中小剂量胰岛素疗法方法简便,安全可靠,并发症少。本组患儿ICA阳性率55%,IAA阳性率30%,经卡方检验均显著高于对照组,推测病毒感染引起自身免疫反应,产生ICA及IAA而致本病发生。     

Vacuolar cytoplasmic phase separation in cultured mammalian cells involves the microfilament network and reduces motional properties of intracellular water

Hep-2, human epithelial carcinoma cells, and human foreskin fibroblasts (FF9 and FF13) were exposed to either an ultrafiltrate (< 50 kD) of human sera or the weak base, procaine hydrochloride, to induce reversible cytoplasmic vacuolization. The formation of vacuoles was shown not to be due to imbibition of medium. Ultrastructural details obtained from various stages of vacuole formation were compared. In both cases of induction vacuoles were irregular and often appeared membraneless, with little in the way of electron-dense content. They started to form in the perinuclear cytoplasm and progressed towards the periphery. Osmotic stress was not involved since mitochondria remained normal throughout a vacuolization episode.
Vacuoles were often seen in close contact with filamentous structures, and this association remained detectable at late stages of the phenomenon. Fluorescent visualization of F-actin confirmed that the vacuoles were frequently bordered by microfilaments. No major metabolic impairment was apparent in vacuolized cells as judged by protein synthesis measurements, but nuclear fluorescence (DNA content) and forward light scatter (nuclear volume) by flow cytometric analysis suggested late S phase and G2 retardation. ¹H-nmr relaxation measurements indicated intracellular water restricted in motional characteristics in vacuolized cells. The possibility of a restricted cytoplasmic phase separation as part of a transient adaptation response is raised, and a hypothesis to explain the findings is discussed.     

Regulation of neuronal differentiation in neuron-enriched primary cultures from embryonic rat cerebra by platelet activating factor and the structurally related glycerol ether lipid, dodecylglycerol.

Primary cultures enriched in neurons dissociated from embryonic rat cerebra were used to demonstrate that platelet activating factor and the structurally related ether glycerolipid, dodecylglycerol, are readily taken up in small amounts by neurons and that they stimulate the differentiation of neurons. The stimulation of neuronal differentiation was observed as a precocious development of axon-like extensions which correlated with a concentration-dependent increase in neuronal-specific enzyme activities. This stimulation of morphological and neurochemical factors by either platelet activating factor or dodecylglycerol was almost completely abolished by triazolam, a known inhibitor of platelet activating factor function. Neither platelet activating factor nor dodecylglycerol at the concentrations used to achieve stimulation of neuronal differentiation compromised the plasma membrane, as indicated by the lack of leakage of cytoplasmic lactic acid dehydrogenase.     

The normally expressed κ immunoglobulin light chain gene repertoire and somatic mutations studied by single-sided specific polymerase chain reaction (PCR); frequent occurrence of features often assigned to autoimmunity

The expressed human κ light chain gene repertoire utilized by healthy individuals was studied by two different single-sided specific PCR techniques to avoid bias for certain V genes. A total of 103 rearranged κ sequences from peripheral blood mononuclear cells from healthy individuals were cloned from cDNA and assigned to the Vκ and Jκ germ-line genes with the closest overall homology. The use of cDNA rather than genomic DNA focused the analysis on activated B cells rich in mRNA. Accordingly, the sequences represented the applied repertoire and almost all were somatically mutated. V genes from the Jκ-proximal duplication unit of the κ locus were almost exclusively used. A total of 65% of the sequences could be assigned to four or five genes: A27 (humkv325), L6 (Vg), L2 (humkv328), and A3 and/or A19. N additions and P nucleotides were quite common and found in 32% and 21% of the sequences, respectively. Extended CDR3s more than nine residues in length were found in 18% of the sequences, and in 71% of cases this was due to insertion of an extra proline residue. This proline was usually explained from the germ-line sequences involved. These results are in good agreement with those of previous repertoire studies using potentially V-gene-biased techniques. Thus, it is clear that restricted V-gene usage, common N and P additions, and extended CDR3 regions are normal features and not, as has been claimed, characteristics of pathological autoantibodies.     

Study on lymphocyte activation and proliferation induced by anti-CD3 McAb

Summary T cell activation and proliferation via CD₃-TCR complex were investigated by lymphocyte DNA synthesis in vitro. Several interfering factors were also discussed. The result indicated that lymphocyte activation and proliferation are calciumdependent. A rise of cytoplasmic free Ca²⁺ quickly following activation with CD₃ McAb is mainly due to intracellular mobilization of Ca²⁺, while lymphocyte proliferation needs both intracellular mobilization of Ca²⁺ as well as influx of extracellular Ca²⁺. It was confirmed that CTX sensitive G protein plays a role in regulating T cell proliferation by pretreatment with CTX suppressing lymphocyte³H-TdR incorporation obviously. PLC and PKC inhibitor neomycin and P. S. S could also decrease T cell proliferation.     

Antineutrophil cytoplasmic antibodies in IgA nephropathy and Henoch-Sch?nlein purpura.

The frequency, isotype, and specificity of antineutrophil cytoplasmic antibodies were investigated in a cross-sectional study of 100 patients with IgA nephropathy and 30 children with Henoch-Sch?nlein purpura. Two of the patients with IgA nephropathy had high titres of antineutrophil cytoplasmic antibodies which were of IgG isotype and confirmed as antimyeloperoxidase antibodies in solid-phase ELISA and inhibition experiments. Antineutrophil cytoplasmic antibodies were not detected in the children with Henoch-Sch?nlein purpura and none of the patients in either group had IgA antineutrophil cytoplasmic antibodies. A further 20 IgA nephropathy and 10 Henoch-Sch?nlein purpura patients were studied longitudinally in different clinical phases at 4-monthly intervals over a 2-year period. None of these patients had or developed antineutrophil cytoplasmic antibodies. We conclude that IgA antineutrophil cytoplasmic antibodies are not involved in the vasculitis of Henoch-Sch?nlein purpura or in the pathogenesis of glomerular injury in IgA nephropathy. The detection of IgG antimyeloperoxidase antibodies in a small minority of IgA nephropathy patients extends the spectrum of diseases associated with autoimmunity to this antigen but is of uncertain significance.     

Antineutrophil cytoplasmic antibodies (ANCA) in idiopathic pulmonary hemosiderosis

Four children were diagnosed with idiopathic pulmonary hemosiderosis (IPH), over a period of 4 years. Retrospectively, antineutrophil cytoplasmic antibodies (ANCA) were studied by indirect immunofluorescence (IIF) and ELISA in 18 sera from these patients, stored at -20°C. ANCA-positive sera, from 1/20 to 1/1, 200 dilution, were found in 3/4 of the patients, by IIF. The patient with the highest titre of ANCA died 3 months later during an acute crisis, the other two patients need a minimal dose of steroids. In one case only, a patient who is still without treatment, had no ANCA. The antibodies anti-myeloperoxidase and anti-pro-teinase-3 were negative or at border line levels. Rheumatoid factor, anti-nuclear (Hep-2), anti-endomysial, anti-reticulin and antibasement membrane antibodies were negative in all sera. The surviving patients were followed-up for more than 10 years with no systemic or renal disease appearences. The presence of serum ANCA may help to classify children with pulmonary haemorrhage and may have a prognostic value.     

与Graves眼病有关的眼肌自身抗原抗体的分子免疫学研究

为探讨Ｇｒａｖｅｓ眼病（ＧＯ）的发病机理，我们对新近发现的眼肌自身抗原及存在于ＧＯ患者血清的眼肌抗体进行了研究。血清取自１８例正常人、１８例活动性ＧＯ、１０例无限征的Ｇｒａｖｅｓ甲亢（ＧＨ）和３例桥本甲状腺炎（ＨＴ）患者。人眼肌膜蛋白经ＧＯ患者混合ＩｇＧ亲和层析后进行ＳＤＳ－聚丙烯酰胺凝胶电泳，显示分子量为４５、２８、５５和６４ｋＤ等蛋白条带。经正常人混合ＩｇＧ亲和层析未能显示上述结果。Ｗｅｓｔｅｒｎ印迹杂交虽然未能证实仅与患者血清作用的独特的眼肌抗原的存在，但６４ｋＤ印迹存在于６１％的ＧＯ、３０％的ＧＨ、０％的ＨＴ患者，正常人仅２２％阳性。抗６４ｋＤ阳性率ＧＯ组明显高于对照组（Ｐ＜０．０５）。眼肌抗体（ＥＭＡｂ）特别是抗６４ｋＤ抗体对于ＧＯ发病机理的作用值得进一步研究。     

Elongation of the cytoplasmic domain,due to a point deletion at exon 7, results in an HLA-C null allele,Cw*0409 N

The development of molecular techniques for HLA typing has allowed the identification of genes previously assigned as serologic blank alleles. Lack or poor cell surface expression has been found for molecules coded by HLA-A, -B, -DRB4, -DRB5, and -DPB1 genes. In this report we describe the first HLA-C gene encoding for a null cell surface molecule. HLA-Cw*0409 N shows a point deletion at position 1095 within exon 7. This mutation provokes a codon reading shift, generating a new translation stop codon 97 bp downstream to that described in alleles normally expressed. This new stop codon location implies the presence of 32 extra amino acid residues in the cytoplasmic domain. Transfection experiments suggest that elongation of the cytoplasmic domain in Cw*0409 N would be the cause of cell surface expression failure, although Cw*0409 N heavy chain is able to create stable complexes with beta2-microglobulin. HLA-C fragment length analysis in a small selected group of samples with B44-Cblk haplotypic associations allowed us to identify two additional subjects showing both a serologic silent Cw*04 allele and a point base deletion at the 3' end of the HLA-C gene. This finding indicates that the allele frequency of Cw*0409 N within serologic C blank alleles would be appreciable, although basically restricted to the (A23)-Cw*0409 N-B*4403-DR7-DQ2 haplotype.