Establishing a diagnostic model for clinical almost tolerance of kidney allograft based upon plasma proteomics / 中华器官移植杂志

Objective:To explore a new method of diagnosing and identifying renal transplantation clinical almost tolerance through a diagnostic model using plasma proteomics.Methods:From November 2011 to November 2012, plasma samples from 43 subjects were collected and divided into the groups of clinical almost tolerance(18 cases), rejection(12 cases)and healthy control(13 cases). Protemic analysis of plasma samples was performed by surface enhanced laser desorption/ionization time of flight mass spectrometry (SELDI-TOF-MS). Differential mass spectrometry peaks were screened and diagnostic model was established by Biomarker Wizard and Biomarker Pattern software. Identification of mass spectrometric peaks of nodes in the diagnostic model was carried out by searching the databases of SWISS-PROT and TrEMBL using ExPASy's TagIdent tool.Results:A total of 21 differential proteins peaks were obtained( P<0.05). Diagnostic model was composed of five mass spectrum peaks of 2 565.15, 1 966.28, 6 674.78, 1 103.27, 1 716.69 and 1 966.28.The sensitivity, specificity and area under the ROC curve of model were 83.3%, 92.0% and 0.951 respectively for diagnosing clinical almost tolerance.Bioinformatic identification results of mass spectrometric peaks of nodes in model were proteins of ANFB, MCH, TFF1, PDYN and PSME3. Conclusions:Establishing a diagnostic mode by plasma proteomics may be effectively employed for diagnosing clinical almost tolerance in kidney transplant.

Experimental study on the in vitro induction of regulatory T cells by umbilical cord mesenchymal stem cells with positive human leukocyte antigen-G / 器官移植

Objective To explore the effect of umbilical cord mesenchymal stem cells with positive human leukocyte antigen(HLA)-G on inducing the production of regulatory T cells(Treg) in vitro.Methods Umbilical cord mesenchymal stem cells were isolated from umbilical cord of neonates. PEGFP-N1-HLA-G plasmid was transfected into the human umbilical cord mesenchymal stem cells by liposome transfection, as PEGFP-N1-HLA-G group. PEGFP-N1 empty vector plasmid was transfected into the human umbilical cord mesenchymal stem cells, as PEGFP-N1 group. The human umbilical cord mesenchymal stem cells without empty vector under the same conditions were set as blank control group. Markers of the umbilical cord mesenchymal stem cells were detected using flow cytometry. The expression of HLA-G protein in each group of cells was identified by Western Blot. After mixed-culturing with CD4+T cells in peripheral blood of healthy subjects for 24 h and 48 h, the proportion of CD4+CD25+Foxp3+Treg in total T cells of each group was detected by flow cytometry. Results CD45, CD34 and HLA-DR presented negative expression on umbilical cord mesenchymal stem cells, while CD29, CD44 and CD105 presented positive expression. HLA-G protein could be expressed in the PEGFP-N1-HLA-G group, which had statistically significant difference compared with the blank control group and PEGFP-N1 group (both P<0.01). After PEGFP-N1-HLA-G group and CD4+T cells were mixed-cultured for 24 h and 48 h, CD4+CD25+Foxp3+Treg accounted for (15.3±1.9)% and (14.3±2.1)% of the total T cells respectively, both of which presented statistically significant difference compared with the blank control group and PEGFP-N1 group (all P<0.05). Conclusions Umbilical cord mesenchymal stem cells with HLA-G gene modified can effectively induce the production of CD4+CD25+Foxp3+Treg in vitro.

Teste de desencadeamento aberto no diagnóstico de alergia à proteína do leite de vaca / Open challenge for the diagnosis of cow's milk protein allergy

OBJETIVO: Relatar os resultados de testes de desencadeamento aplicados em crianças alimentadas com dieta de exclusão das proteínas do leite de vaca. DESCRIÇÃO: Estudo transversal que avaliou testes de desencadeamento oral aberto, com leite de vaca, realizados sob supervisão em ambiente hospitalar por 2,5 horas e ambulatoriamente por 30 dias quando não ocorreu reação imediata. Foram incluídos 121 pacientes, com idades entre 4 e 95 meses. O teste de desencadeamento com leite de vaca foi positivo em 28 (23,1 por cento) pacientes. Manifestação clínica de alergia ao leite de vaca diferente da apresentada por ocasião da suspeita diagnóstica ocorreu em 12 (42,9 por cento) pacientes com desencadeamento positivo. O desencadeamento positivo foi mais frequente (p = 0,042) nos pacientes alimentados com fórmulas extensamente hidrolisadas ou de aminoácidos (30,3 por cento) quando comparados com os alimentados com outras dietas de exclusão (14,5 por cento). CONCLUSÃO: O teste de desencadeamento permitiu que fosse suspensa a dieta de exclusão de grande parte dos pacientes.

OBJECTIVES: To report the results of open challenge tests performed in children fed with cow's milk-free diet. DESCRIPTIONS: Cross-sectional study evaluating cow's milk open challenge performed under supervision in a hospital setting during 2.5 hours and ambulatory follow-up for 30 days when no immediate reaction occurred. One hundred and twenty-one patients were included, with ages between 4 and 95 months. Cow's milk open challenge tests were positive in 28 patients (23.1 percent). A clinical manifestation of cow's milk allergy different from the one presented at diagnosis occurred in 12 (24.9 percent) patients with positive challenge. Positive challenge was more frequent (p = 0.042) in patients fed with extensively hydrolyzed formulae or amino acid-based formulae (30.3 percent) when compared to those fed with other exclusion diets (14.5 percent). CONCLUSION: Open challenge allowed the interruption of exclusion diet in a significant proportion of the patients.

Introduction to Autoimmune Disease

The immune system maintains the integrity of our bodies by warding off intruding microorganisms, but by sustaining tolerance to our own tissues. The immunologic tolerance is established by several layers of safeguards, including physical elimination of self-reactive lymphocytes during their development in the central lymphoid organs, anergy induction in autoreactive lymphocytes before their emigration to the periphery, or production regulatory T lymphocytes that suppress the activation, proliferation, and differentiation of various effector cells. The major regulatory T lymphocytes display their phenotype as CD4(+)CD25(+)Foxp3(+) and constitute about 10% of the peripheral T lymphocytes. Even with these safeguards, the immunologic tolerance sometimes fails and generates autoimmune diseases. Scientists studying the pathogenesis of autoimmune diseases pay particular attention to a CD4(+) T lymphocytes subset, Th17 lymphocytes, distinct from Th1 and Th2. Th17 produces diverse proinflammatory cytokines including IL-17 and TNF-alpha. Th17 and these cytokines are causatively associated with many episodes of autoimmune diseases. Accumulated data reveal the critical role of Th17 cells in the pathology of autoimmunity and portray them as an important target in the treatment of various autoimmune diseases. In this article, we will describe the main characteristics of regulatory T cells and Th17 cells and their cellular and molecular mechanisms of protective or destructive functions, respectively.

Introduction to Autoimmune Disease

The immune system maintains the integrity of our bodies by warding off intruding microorganisms, but by sustaining tolerance to our own tissues. The immunologic tolerance is established by several layers of safeguards, including physical elimination of self-reactive lymphocytes during their development in the central lymphoid organs, anergy induction in autoreactive lymphocytes before their emigration to the periphery, or production regulatory T lymphocytes that suppress the activation, proliferation, and differentiation of various effector cells. The major regulatory T lymphocytes display their phenotype as CD4(+)CD25(+)Foxp3(+) and constitute about 10% of the peripheral T lymphocytes. Even with these safeguards, the immunologic tolerance sometimes fails and generates autoimmune diseases. Scientists studying the pathogenesis of autoimmune diseases pay particular attention to a CD4(+) T lymphocytes subset, Th17 lymphocytes, distinct from Th1 and Th2. Th17 produces diverse proinflammatory cytokines including IL-17 and TNF-alpha. Th17 and these cytokines are causatively associated with many episodes of autoimmune diseases. Accumulated data reveal the critical role of Th17 cells in the pathology of autoimmunity and portray them as an important target in the treatment of various autoimmune diseases. In this article, we will describe the main characteristics of regulatory T cells and Th17 cells and their cellular and molecular mechanisms of protective or destructive functions, respectively.

Células T regulatórias naturais (T REGS) em doenças reumáticas: [revisão] / Natural regulatory T cells in rheumatic diseases: [review]

O sistema imune sadio deve manter o balanço entre a capacidade de responder a agentes infecciosos e de sustentar a autotolerância. A ausência de resposta adequada submete o indivíduo aos efeitos deletérios da invasão por patógenos, ao passo que o sistema respondendo de modo exacerbado pode gerar respostas inflamatórias prejudiciais. Acreditava-se que os mecanismos de deleção clonal e anergia fossem os mecanismos essenciais no controle de clones de linfócitos T auto-reativos. Apesar das evidências funcionais a favor da existência de células T supressoras, por muitos anos a imunologia falhou em identificar suas características fenotípicas e confirmar sua existência, motivo pelo qual o tema passou por longo período de descrédito. A recente demonstração de diferentes fenótipos de células, agora chamadas células T regulatórias, reintroduziu o paradigma de que a auto-reatividade é ativamente regulada também por subtipos particulares de linfócitos. Este tema é de grande interesse contemporâneo e a literatura está repleta de estudos descrevendo novos subtipos de células regulatórias, bem como a função, o fenótipo e a freqüência em condições fisiológicas e patológicas. Nesse universo, destaca-se o subtipo mais importante de células com função imunorregulatória, conhecido como células T regulatórias naturais (T REGS). Representando cerca de 5 por cento dos linfócitos T CD4 do sangue periférico, são células caracterizadas pela expressão constitutiva das moléculas FOXP3, GITR, CTLA-4 e altos níveis de CD25. As alterações deletérias nesta população resultam o desencadeamento de doenças auto-imunes em camundongos, muito semelhantes às doenças auto-imunes humanas. A presente revisão aborda os conhecimentos básicos sobre as T REGS e seu estudo em doenças reumáticas de classificação auto-imune, abrindo perspectivas para o entendimento dos mecanismos de regulação periférica e sobre a fisiopatologia dessas enfermidades. Apresenta, ainda, a perspectiva de futuras abordagens...

The healthy immune system must keep the delicate balance between the capacity to respond to exogenous antigens and to keep the tolerance to endogenous antigens. In the absence of an adequate response to exogenous agents the individual is subjected to the deleterious effect of the invasion for pathogens. On the other hand, if the immune system responds in an unwary exacerbated way harmful inflammatory consequences may result. Well-established mechanisms of maintaining self-tolerance include clonal deletion and anergy. Despite the functional evidence in favor of the existence of suppressor T cells, for many years immunologists failed to identify the phenotypic characteristics and to confirm the existence of these lymphocytes. The recent demonstration of different phenotypes of cells, now designated regulatory T cells, reintroduced the paradigm of active regulation of auto-reactivity by particular subtypes of lymphocytes. This subject is of great interest in the contemporary literature. It has been shown that excess regulatory function may be associated with increased susceptibility to infectious and neoplastic diseases. On the other hand decreased regulatory function may cause autoimmunity. In fact, several experimental models of diverse autoimmune conditions have been developed by decreasing or abolishing regulatory T cells. Counterpart of this phenomenon has been sought for in several human autoimmune diseases. At this moment it seems that the most important subtype of regulatory cells are the natural regulatory T cells (TREGS), which represent about 5 percent of peripheral blood CD4 T lymphocytes. These cells are characterized by the constitutive expression of FOXP3, GITR, CTLA-4 and high levels of CD25. The present article reviews the basic knowledge on the TREGS and the several studies describing the status and function of these cells in autoimmune rheumatic diseased.

Prolongation of cardiac allograft survival in mice by HLA-derived peptide plus subtherapeutic CsA / 中华器官移植杂志

Objective To study the effect of synthetic HLA-derived peptide (P), HLA-B*2702.75-84, on the mean survival time (MST) of cardiac allografts in mice.Methods NIH mice cardiac allografts were heterotopically transplanted into the posterior of Balb/c ears. The HLA-derived peptide in combination with a subtherapeutic dose of CsA were perioperatively administrated. The pulsation of the cardiac allograft observed under the operating microscope was considered as the indication of the cardiac allograft surviving time or rejection. Results MST was ( 7.5? 0.5) days in untreated control group, ( 8.5? 1.5) days in CsA group and ( 7.0? 1.5) days in control peptide or P groups respectively, whereas MST was ( 26.5? 3.5) days in experimental group.Conclusion The synthetic HLA-derived peptide combined with subtherapeutic CsA can significantly prolong cardiac allograft survival in mice as compared with control groups.