A novel mechanism for immune regulation after human lung transplantation.

OBJECTIVE: Lung transplantation is therapeutic for end-stage lung disease, but survival is limited due to bronchiolitis obliterans syndrome and restrictive chronic lung allograft dysfunction. We sought a common denominator in lung transplant recipients, analyzing risk factors that trigger immune responses that lead to bronchiolitis obliterans syndrome. METHODS: We collected blood from patients who underwent lung transplant at our institution. Exosomes were isolated from the sera of recipients with risk factors for chronic rejection and from stable recipients. Exosomes were analyzed with western blot, using antibodies to lung self-antigens K alpha 1 tubulin and collagen-V, costimulatory molecules (costimulatory molecule 80, costimulatory molecule 86), transcription factors (nuclear factor kappa-light-chain-enhancer of activated B cells, hypoxia-inducible factor 1α, Class II Major Histocompatibility Complex Transactivator), and 20S proteasome. RESULTS: Of the 90 patients included, we identified 5 with grade 3 primary graft dysfunction, 5 without, 15 with respiratory viral infection, 10 with acute rejection, 10 with donor-specific antibodies (DSA), 5 without DSA, and 10 who were stable for exosome isolation. Recipients with grade 3 primary graft dysfunction, respiratory viral infection, acute rejection, and DSA had exosomes containing self-antigens; exosomes from stable recipients did not. Exosomes from recipients with grade 3 primary graft dysfunction, acute rejection, and DSA also demonstrated costimulatory molecule 80, costimulatory molecule 86, major histocompatibility complex class II, transcription factor, and 20S proteasome. CONCLUSIONS: Transplanted lungs with grade 3 primary graft dysfunction, symptomatic respiratory viral infection, acute rejection, and immune responses induce exosomes that contain self-antigens, costimulatory molecules, major histocompatibility complex class II, transcription factors, and 20S proteasome. Release of circulating exosomes post-transplant from the aforementioned stress-inducing insults augment immunity and may play an important role in the pathogenesis of bronchiolitis obliterans syndrome.

Immunoglobulin G4-related immune responses to common food antigens in patients with ulcerative colitis and Crohn's disease.

BACKGROUND/AIMS: It is unclear whether IgG4-related immune responses to food can play a role in the pathogenesis of inflammatory bowel disease (IBD). The aim of the present study was to investigate the serum levels of IgG4 to common food antigens in patients with ulcerative colitis (UC), Crohn's disease (CD), and healthy controls. MATERIALS AND METHODS: Thirty-six patients with CD (n=12) or UC (n=24) and 36 sex- and age-matched healthy individuals (mean age, 49 years) participated in the study. Serum levels of IgG4 to 90 common food antigens were measured. The number of subjects with positivity, defined by cut-off values ≥0.7 U/mL, was compared. RESULTS: Serum titers of IgG4 to salmon, onion, shrimp, cuttlefish, eel, millet, gluten, soybean, and coconut in patients with IBD were significantly or tended to be higher than those in the control group. Serum levels of IgG4 to salmon, millet, and onion in patients with CD were significantly or tended to be higher than those in the control group. Serum titers of IgG4 to cuttlefish and onion in patients with UC tended to be higher than those in the control group. The number of subjects with positivity to cod, tuna, mackerel, oat, pea, peanut, and coconut was significantly higher in patients with CD than in healthy controls. The number of subjects with positivity to kiwi and cuttlefish was significantly higher in patients with UC than in controls. CONCLUSION: Patients with IBD shows higher serum levels of IgG4 to diverse food antigens. Patients with CD present IgG4-related immune reactions to more foods than patients with UC.

B-cell-specific accumulation of inclusion bodies loaded with HLA class II molecules in patients with mucolipidosis II (I-cell disease).

BACKGROUND: I-cell disease is characterized by the presence of vacuole-like inclusions in lymphocytes. However, the nature and clinical significance of these inclusions have seldom been characterized. In this study, the authors tried to elucidate the distribution in different lymphocyte subpopulations, and the histological nature of the inclusions. METHODS: Blood samples from three unrelated patients were analyzed. Lymphocyte subpopulations were separated using monoclonal antibodies conjugated to immunomagnetic beads. Cytochemical studies were performed using FITC-conjugated lectins. The expressions of surface and cytoplasmic class II molecules were analyzed by flow cytometry. RESULTS: Virtually all B cells from the patients contained the inclusions. In contrast, CD4+ T cells, CD8+ T cells, natural killer cells, monocytes, or neutrophils did not contain the inclusions. Both fibroblasts and B cells from I-cell patients were stained intensely by multiple FITC-conjugated lectins with distinct binding profiles. The inclusions of B cells were stained intensely by fluorescence-conjugated antibodies against class II antigens. CONCLUSIONS: Inclusions in I-cell disease reflect the accumulation of HLA class II molecules within B cells. These results suggest a potential role for N-acetylglucosamine-1-phosphotransferase in immune functions. Furthermore, the fact that only B cells contain the inclusions provides a novel diagnostic aid for the diagnosis of I-cell disease.

Circulating histocompatibility antigen (HLA) gene products may help differentiate benign from malignant indeterminate pulmonary lesions.

BACKGROUND: This study explores the potential diagnostic utility of soluble Human Leukocyte Antigen (sHLA) molecules differentially released by lung adenocarcinoma and benign lung lesions. METHODS: Conditioned media from the NSCLC cell lines H358 and H1703 were immunoblotted for soluble isoforms of major histocompatibility complex (MHC) class I (ABC) and II (DRB1, DMB, and DQ) antigens. Sera from 25 patients with benign and 25 patients with malignant lesions were similarly evaluated to appraise the potential diagnostic value. RESULTS: Higher concentrations of soluble HLA class I molecules were observed in conditioned medium for the highly-invasive H1703 cell line, relative to the more indolent H358 cells. Evaluation of these markers against a cohort of 50 cases demonstrated that patients with malignant lesions possess higher levels of HLA class I and II molecules relative to those with benign lesions (p < 0.05), with exception to the primary isoform, DQA1, which was suppressed in malignancies. An analysis of biomarker performance via ROC analysis revealed promising performance (AUC > 0.75) for DMB and the 26 kDa isoform of DQ in distinguishing lesion pathology. CONCLUSIONS: Soluble HLA molecules may have diagnostic value for early-stage NSCLC. Validation studies are currently underway using sera from a lung cancer screening cohort.

Anti-HLA Antibodies After Precocious Transplantectomy by Vascular Thrombosis.

BACKGROUND: Our objective in this study was to determine the effects of early renal transplantectomy on patients and the production of anti-human leukocyte antigen (anti-HLA) antibodies. METHODS: Between January 2003 and May 2017, we analyzed a group of patients for the presence of specific HLA class I and/or II donor-specific antibodies (DSA), their panel-reactive antibodies (PRA), and the time period in which the antibodies were still detectable after transplantectomy. RESULTS: Anti-HLA antibodies were detected in 60.8% of patients, 60.8% and 52.2% of those patients had anti-class I and anti-class II antibodies, respectively. DSA were detected in 91.7% of the anti-HLA class I patients. Class II DSA were detected all of the patients with anti-HLA class II antibodies. The average (mean ± SD) PRA levels in our patients after transplantectomy was 60 ± 34% in class I and 63 ± 36% in class II. CONCLUSION: Anti-HLA antibodies can be detected well after transplantectomy. Even if the kidney allograft had been transplanted for only a short time, when the intensity of immunosuppression was the highest, many patients developed anti-HLA antibodies. The patients who continued with immunosuppression after transplantectomy did not develop anti-HLA antibodies.

Immune Activation of Platelets in Response to Serial Phlebotomy in Pigtailed Macaques (Macaca nemestrina).

Serial phlebotomy is a common sampling practice for repeated-measures studies in biomedical research. In NHP, the effect of serial blood collection on RBC parameters has been characterized, but the effects on platelet parameters and other aspects of the hemogram have not been well studied. We sought to characterize the circulating platelet phenotype throughout the course of 7 serial phlebotomies spanning 30 d in pigtailed macaques (Macaca nemestrina). Phlebotomy was performed on 23 animals at days 0, 2, 4, 7, 10, 21, and 30 to quantify the circulating platelet count and markers of both hemostatic and immune platelet activation. Platelet immune activation was characterized by increases in surface MHC class I and II expression and increases in circulating platelet-leukocyte aggregates. These changes occurred in the absence of increases in the prohemostatic markers P-selectin and CD40L and without evidence of adverse clinical effects. Mild increases in platelet count, mean platelet volume, and immune activation occurred early in the study. After day 21, mean platelet volume and other hematologic parameters returned to baseline while changes in platelet count and immune activation were greater than during the first 10 d of the study. These data demonstrate that serial phlebotomy in NHP has delayed effects on platelet parameters, which may be a source of clinically silent, immunologic and physiologic variability within repeated measures studies. The impact of these effects on research aims should be considered when designing protocols requiring serial phlebotomy in NHP.

Macrophage Migration Inhibitory Factor Induces Inflammation and Predicts Spinal Progression in Ankylosing Spondylitis.

OBJECTIVE: To investigate the role of macrophage migration inhibitory factor (MIF) in the pathogenesis of ankylosing spondylitis (AS). METHODS: Patients who met the modified New York criteria for AS were recruited for the study. Healthy volunteers, rheumatoid arthritis patients, and osteoarthritis patients were included as controls. Based on the annual rate of increase in modified Stoke AS Spine Score (mSASSS), AS patients were classified as progressors or nonprogressors. MIF levels in serum and synovial fluid were quantitated by enzyme-linked immunosorbent assay. Predictors of AS progression were evaluated using logistic regression analysis. Immunohistochemical analysis of ileal tissue was performed to identify MIF-producing cells. Flow cytometry was used to identify MIF-producing subsets, expression patterns of the MIF receptor (CD74), and MIF-induced tumor necrosis factor (TNF) production in the peripheral blood. MIF-induced mineralization of osteoblast cells (SaOS-2) was analyzed by alizarin red S staining, and Western blotting was used to quantify active ß-catenin levels. RESULTS: Baseline serum MIF levels were significantly elevated in AS patients compared to healthy controls and were found to independently predict AS progression. MIF levels were higher in the synovial fluid of AS patients, and MIF-producing macrophages and Paneth cells were enriched in their gut. MIF induced TNF production in monocytes, activated ß-catenin in osteoblasts, and promoted the mineralization of osteoblasts. CONCLUSION: Our findings indicate an unexplored pathogenic role of MIF in AS and a link between inflammation and new bone formation.

Imunohematologia veterinária: antígenos eritrocitários caninos / Veterinary immunohematology: canine erythrocyte antigen / Inmunohematología veterinaria: antígenos eritrocitarios caninos

A imunohematologia veterinária vem ganhando interesse nos últimos anos devido a maior acessibilidade a tecnologias de detecção de antígenos e anticorpos, interesse dos donos e médicos veterinários em buscar uma melhor qualidade de vida para os animais e as necessidades de transfusões com o menor índice possível de reações indesejadas. Os cães possuem antígenos presentes na membrana de suas células vermelhas, podendo causar reações durante e após transfusões. Diferentemente de humanos e felinos, cães não possuem anticorpos naturais para os principais antígenos, a priori podendo ser transfundidos com qualquer tipo sanguíneo sem consequências posteriores, porém, se submetidos a uma segunda transfusão, sendo essa de um tipo sanguíneo incompatível e previamente sensibilizados, as chances de ocorrer reações transfusionais graves aumentam drasticamente, ocasionando danos ao animal, podendo levá-lo à morte. Por conta desses riscos se faz necessário uma maior atenção aos tipos sanguíneos desses animais onde 8 sistemas são reconhecidos internacionalmente classificados como sistema DEA, sendo eles DEA 1 e seus subtipos (DEA 1.1; DEA1.2; DEA 1.3); DEA 3; DEA 4; DEA 5; DEA 6; DEA 7 e DEA 8, e recentemente um novo sistema denominado Dal. Não há disponível ainda soros para os sistemas DEA 6 e DEA 8, tornando a pesquisa sobre esses antígenos dificultosa.(AU)

Veterinary immunohematology is gaining interest in recent years due to greater accessibility to antigen and antibody detection technologies, the interests of pet owners and veterinarians in seeking a better quality of life for animals, and requirement of transfusions with the lowest possible rate of collateral reactions. Dogs have antigens present in the membrane of their red blood cells that can cause reactions during and after transfusions. Unlike humans and cats, dogs do not have natural antibodies to the key antigens, and a priori they can be transfused with any type of blood without any further consequences. However, if they are ever subjected to a second transfusion, if using incompatible blood types and being previously sensitized, the likelihood of having serious transfusion reactions drastically increase, causing damage to the animal, which may even lead it to death. Due to those risks, greater attention is required to the blood type of those animals, which present 8 systems, internationally recognized and classified as the DEA system, namely DEA 1 and its subtypes (DEA 1.1; DEA 1.2; DEA 1.3); DEA 3; DEA 4; DEA 5; DEA 6; DEA 7 and DEA 8, and recently a new system referred to as Dal. No serum is yet available for DEA 6 and DEA 8 systems, hindering the research on those antigens.(AU)

La inmunohematología veterinaria ha ganado atención en los últimos años debido mayor accesibilidad a tecnologías de detección de antígenos y anticuerpos, interés de dueños y médicos veterinarios en buscar mejor calidad de vida para los animales y las necesidades de transfusiones con menor índice posible de reacciones indeseadas. Los perros poseen antígenos presentes en la membrana de sus células rojas, pudiendo causar reacciones durante y después de transfusiones. Diferentemente de humanos y felinos, perros no tienen anticuerpos naturales para los principales antígenos, a priori, pudiendo ser transfundidos con cualquier tipo de sangre sin consecuencias posteriores, todavía, si sometidos a una segunda transfusión, siendo esa de un tipo sanguíneo incompatible y previamente sensibilizados, la posibilidad de ocurrir reacciones transfusional grave aumenta drásticamente, ocasionando daños al animal, pudiendo llevarlo a la muerte. Por esos riesgos se hace necesario más atención a los tipos sanguíneos de esos animales, donde 8 sistemas son reconocidos internacionalmente y clasificados como sistema DEA, siendo ellos DEA 1 y sus subtipos (DEA 1.1; DEA 1.2; DEA 1.3); DEA 3; DEA 4; DEA 5; DEA 6; DEA 7 y DEA 8, y recién un nuevo sistema denominado Dal. No hay aún disponible sueros para los sistemas DEA 6 y DEA 8, haciendo dificultosa la investigación sobre esos antígenos.(AU)

Antibody-Mediated Rejection in Kidney Transplantation Without Evidence of Anti-HLA Antibodies?

INTRODUCTION: The definition of antibody-mediated rejection (AMR) is based on serologic (presence and/or development of donor-specific anti-HLA antibodies [DSAs]) and histologic (C4d deposition and endothelial damage) criteria. However, several cases of AMR have been described without C4d deposition, and other cases of histologic AMR without DSAs, which could be driven by other non-HLA alloantibodies such as anti-MICA or anti-angiotensin II type I receptor (AT1R). Here we studied clinical and histologic humoral rejection in kidney transplant recipients without evidence of anti-HLA antibodies. MATERIALS AND METHODS: Fifteen kidney transplant recipients with AMR defined as C4d+ and/or histologic g+ptc without anti-HLA antibodies in screening test were studied. Sera at the moment of biopsy and 2 months earlier were studied for anti-HLA antibodies by Luminex, in neat, diluted 1/160, and sera after treatment with dithiothreitol (DTT) and confirmed by single-antigen test. The anti-AT1R was measured by enzyme-linked immunosorbent assay. RESULTS: A lack of anti-HLA and MICA antibodies was confirmed after anti-HLA screening test in all conditions (neat, diluted, and DTT-treated) and de novo development of AT1R antibodies was ruled out. Nevertheless, after single-antigen test, 3 patients were identified with a weak reaction against class I antigen and another 4 patients against class II antigen. Due to the lack of locus-C typing in the donors, the DSA assignment cannot be confirmed, whereas anti-HLA class II antigens were DSA. CONCLUSIONS: A low sensitivity in the screening of anti-HLA antibody testing was observed. Our results suggest performing single-antigen test in seronegative patients with clinical humoral rejection after screening to confirm the presence of DSA.

Lack of association between alopecia areata and HLA class I and II in a southeastern Brazilian population

Abstract: Background: Alopecia areata (AA) is a common disorder of unknown etiology that affects approximately 0.7% to 3.8% of patients among the general population. Currently, genetic and autoimmune factors are emphasized as etiopathogenic. Studies linking Human Leukocyte Antigens (HLA) to AA have suggested that immunogenetic factors may play a role in the disease's onset/development. Objectives: To investigate an association between AA and HLA class I/II in white Brazilians. Methods: Patients and control groups comprised 33 and 112 individuals, respectively. DNA extraction was performed by column method with BioPur kit. Allele's classification was undertaken using the PCR-SSO technique. HLA frequencies were obtained through direct counting and subjected to comparison by means of the chi-square test. Results: Most patients were aged over 16, with no familial history, and developed partial AA, with no recurrent episodes. Patients showed a higher frequency of HLA-B*40, HLA-B*45, HLA-B*53 and HLA-C*04 compared with controls, although P was not significant after Bonferroni correction. Regarding HLA class II, only HLA-DRB1*07 revealed statistical significance; nevertheless, it featured more prominently in controls than patients (P=0.04; Pc=0.52; OR=0.29; 95%; CI=0.07 to 1.25). P was not significant after Bonferroni correction. Conclusions: The development of AA does not seem to be associated with HLA in white Brazilians, nor with susceptibility or resistance. The studies were carried out in populations with little or no miscegenation, unlike the Brazilian population in general, which could explain the inconsistency found.

[Relationship Levels of Brain Natriuretic Peptide in the Blood and the Immune Response in Humans.]

Revealed elevated Nt-pro-BNP concentration in 11% of healthy people aged 19-24 years and 22% of middle-aged (34-55 years); in the case of the metabolic syndrome increasing Nt-pro-BNP concentration in blood is set to 90%. Elevated levels of Nt-pro-BNP in peripheral blood occurs with increasing age; set higher peptide concentration in women. Inhibition of lymphoproliferation and differentiation of lymphocytes with increasing content of Nt-pro-BNP in blood is associated with deficiency of IL-2 content due to increased concentration and IL-10. Immunosuppressive effect of IL-10 appears more at innate immune reactions decrease blood levels of naive T-lymphocytes CD45RA+, natural killer cells, T cell adhesion receptor (CD56+) and adhesion receptor ligand (CD62L+). To prevent loss of cell-cell pool, the effect is activated Nt-pro-BNP. No statistically significant correlation between increased Nt-pro-BNP concentration in blood and the content of serum IgM, IgG, IgA, IgE, IL-6, TNF-α, IFN-γ, CEC Clq and C3d, as well as glucose, hemoglobin, transferrin, iron and free fatty acids in healthy people.

Interaction of MIF Family Proteins in Myocardial Ischemia/Reperfusion Damage and Their Influence on Clinical Outcome of Cardiac Surgery Patients.

AIMS: Cardiac surgery involves myocardial ischemia/reperfusion (I/R) with potentially deleterious consequences. Macrophage migration inhibitory factor (MIF) is a stress-regulating chemokine-like cytokine that protects against I/R damage, but functional links with its homolog, d-dopachrome tautomerase (MIF-2), and the circulating soluble receptor CD74 (sCD74) are unknown. In this study, we investigate the role of MIF, MIF-2, sCD74, and MIF genotypes in patients scheduled for elective single or complex surgical procedures such as coronary artery bypass grafting or valve replacement. RESULTS: MIF and MIF-2 levels significantly increased intraoperatively, whereas measured sCD74 decreased correspondingly. Circulating sCD74/MIF complexes were detectable in 50% of patients and enhanced MIF antioxidant activity. Intraoperative MIF levels were independently associated with a reduced risk for the development of atrial fibrillation (AF) (odds ratio 0.99 [0.98-1.00]; p=0.007). Circulating levels of MIF-2, but not MIF, were associated with an increased frequency of organ dysfunction and predicted the occurrence of AF (area under the curve [AUC]=0.663; p=0.041) and pneumonia (AUC=0.708; p=0.040). Patients with a high-expression MIF genotype exhibited a reduced incidence of organ dysfunction compared with patients with low-expression MIF genotypes (3 vs. 25; p=0.042). INNOVATION: The current study comprehensively highlights the kinetics and clinical relevance of MIF family proteins and the MIF genotype in cardiac surgery patients. CONCLUSION: Our findings suggest that increased MIF levels during cardiac surgery feature organ-protective properties during myocardial I/R, while the soluble MIF receptor, sCD74, may enhance MIF antioxidant activity. In contrast, high MIF-2 levels are predictive of the development of organ dysfunction. Importantly, we provide first evidence for a gene-phenotype relationship between variant MIF alleles and clinical outcome in cardiac surgery patients.

Immune and Epstein-Barr virus gene expression in cerebrospinal fluid and peripheral blood mononuclear cells from patients with relapsing-remitting multiple sclerosis.

BACKGROUND: Gene expression analyses in paired cerebrospinal fluid (CSF) and peripheral blood mononuclear cells (PBMC) from patients with multiple sclerosis (MS) are restrained by the low RNA amounts from CSF cells and low expression levels of certain genes. Here, we applied a Taqman-based pre-amplification real-time reverse-transcription polymerase chain reaction (RT-PCR) (PreAmp RT-PCR) to cDNA from CSF cells and PBMC of MS patients and analyzed multiple genes related to immune system function and genes expressed by Epstein-Barr virus (EBV), a herpesvirus showing strong association with MS. Using this enhanced RT-PCR method, we aimed at the following: (1) identifying gene signatures potentially useful for patient stratification, (2) understanding whether EBV infection is perturbed in CSF and/or blood, and (3) finding a link between immune and EBV infection status. METHODS: Thirty-one therapy-free patients with relapsing-remitting MS were included in the study. Paired CSF cells and PBMC were collected and expression of 41 immune-related cellular genes and 7 EBV genes associated with latent or lytic viral infection were determined by PreAmp RT-PCR. Clinical, radiological, CSF, and gene expression data were analyzed using univariate and multivariate (cluster analysis, factor analysis) statistical approaches. RESULTS: Several immune-related genes were differentially expressed between CSF cells and PBMC from the whole MS cohort. By univariate analysis, no or only minor differences in gene expression were found associated with sex, clinical, or radiological condition. Cluster analysis on CSF gene expression data grouped patients into three clusters; clusters 1 and 2 differed by expression of genes that are related mainly to innate immunity, irrespective of sex and disease characteristics. By factor analysis, two factors grouping genes involved in antiviral immunity and immune regulation, respectively, accurately discriminated cluster 1 and cluster 2 patients. Despite the use of an enhanced RT-PCR method, EBV transcripts were detected in a minority of patients (5 of 31), with evidence of viral latency activation in CSF cells or PBMC and of lytic infection in one patient with active disease only. CONCLUSIONS: Analysis of multiple cellular and EBV genes in paired CSF cell and PBMC samples using PreAmp RT-PCR may yield new information on the complex interplay between biological processes underlying MS and help in biomarker identification.

43 kDa and 66 kDa, two blood stage antigens induce immune response in Plasmodium berghei malaria.

The hunt for an effective vaccine against malaria still continues. Several new target antigens as candidates for vaccine design are being explored and tested for their efficacy. In the present study the sera from mice immunized with 24,000 x g fraction of Plasmodium berghei has been used to identify highly immunogenic blood stage antigens. The protective antibodies present in immune sera were covalently immobilized on CNBr activated sepharose 4B and used for affinity chromatography purification of antigens present in blood stages of P. berghei. Two polypeptides of 66 and 43 kDa molecular weights proved to be highly immunogenic. They exhibited a strong humoral immune response in mice as evident by high titres in ELISA and IFA. Protective immunity by these two antigens was apparent by in vivo and in vitro studies. These two proteins could further be analysed and used as antigens in malaria vaccine design.

Accumulation of functionally immature myeloid dendritic cells in lymph nodes of rhesus macaques with acute pathogenic simian immunodeficiency virus infection.

Myeloid dendritic cells (mDC) are key mediators of innate and adaptive immunity to virus infection, but the impact of HIV infection on the mDC response, particularly early in acute infection, is ill-defined. We studied acute pathogenic simian immunodeficiency virus (SIV) infection of rhesus macaques to address this question. The mDC in blood and bone marrow were depleted within 12 days of intravenous infection with SIVmac251, associated with a marked proliferative response. In lymph nodes, mDC were apoptotic, activated and proliferating, despite normal mDC numbers, reflecting a regenerative response that compensated for mDC loss. Blood mDC had increased expression of MHC class II, CCR7 and CD40, whereas in lymph nodes these markers were significantly decreased, indicating that acute infection induced maturation of mDC in blood but resulted in accumulation of immature mDC in lymph nodes. Following SIV infection, lymph node mDC had an increased capacity to secrete tumour necrosis factor-α upon engagement with a Toll-like receptor 7/8 ligand that mimics exposure to viral RNA, and this was inversely correlated with MHC class II and CCR7 expression. Lymph node mDC had an increased ability to capture and cleave soluble antigen, confirming their functionally immature state. These data indicate that acute SIV infection results in increased mDC turnover, leading to accumulation in lymph nodes of immature mDC with an increased responsiveness to virus stimulation.

Combination therapy with thymosin alpha1 and dexamethasone helps mice survive sepsis.

Immune dysfunction is a major cause of mortality in septic patients. Current evidence indicates an important role for dendritic cells (DCs) in the pathophysiology of immune dysfunction, and these cells are potential targets of immunomodulation therapies. In the present study, our aim was to enhance the resistance of endotoxemic mice to bacterial translocation and secondary infection and to improve the outcome of these infections using a combination therapy consisting of thymosin alpha1 and dexamethasone in a timely manner according to the changes of DCs' number. The effect of treatment with dexamethasone (DXM) and thymosin alpha1 (Tα1) on DCs was investigated by examining their number, MHCII and CD86 expression and their capacity to induce T cell activation. Endotoxemic mice were randomly divided into five treatment groups. The survival rates, the levels of TNF-α and IL-10, the occurrence of bacterial translocation, and the ability to clear secondary infections were determined. Additionally, the behavior of DCs over time was also evaluated. Tα1 induced significant increases in DC numbers in vivo, whereas DXM reduced cell numbers both in vitro and in vivo. However, neither drug induced significant changes in the capacity of DCs to induce T cell activation or their expression of MHCII or CD86. Among the five treatment groups, the mice treated with a combination of DXM and Tα1 had the highest survival rate; this increased survival was associated with a decrease in bacterial translocation to extra-intestinal organs and an enhanced ability to eradicate secondary infections by reversing the change in DC numbers during endotoxemia. Immunomodulatory therapy that combines Tα1 and DXM in a timely manner and was based on changes in DCs enhanced the resistance of endotoxemic mice to bacterial translocation and secondary infections, improving the outcome of the infection.

Peripheral blood CD8αα+CD11c+MHC-II+CD3- cells attenuate autoimmune glomerulonephritis in rats.

In an anti-glomerular basement membrane (GBM) glomerulonephritis (GN) model, GN-resistant Lewis rats naturally recover from early glomerular inflammation. Here we investigated recovery mechanisms for development of a potential immunotherapy for autoimmune GN. Our previous studies suggested that glomeruli-infiltrating leukocytes with a phenotype of CD8αα+CD11c+MHC-II+CD3- (GIL CD8αα+ cells) were responsible for recovery through induction of T-cell apoptosis. Now, we identified peripheral blood CD8αα+CD11c+MHC-II+CD3- cells (PBMC CD8αα+CD3- cells), which shared 9 markers with GIL CD8αα+ cells. Upon incubation, PBMC CD8αα+CD3- cells displayed a morphology resembling that of dendritic cells. Similar to GIL CD8αα+ cells, PBMC CD8αα+CD3- cells were capable of inducing T-cell apoptosis in vitro. Hence, PBMC CD8αα+CD3- cells were likely the precursor of GIL CD8αα+ cells. We next tested their potential in vivo function. PBMC CD8αα+CD3- cells were able to infiltrate inflamed but not normal glomeruli. Isolated PBMC CD8αα+CD3- cells of Lewis rats were transferred into GN-prone Wistar-Kyoto rats at early inflammatory stage (days 17-25). When examined at day 45, both histopathology and blood urea nitrogen/serum creatinine level showed significantly attenuated GN in 80% of cell recipient Wistar-Kyoto rats. Separate experiments verified infiltration of transferred Lewis PBMC CD8αα+CD3- into the glomeruli, accompanied with apoptotic CD4+ T cells in the glomeruli of the recipient Wistar-Kyoto rats. Thus, PBMC CD8αα+CD3- cells of Lewis rats were able to terminate ongoing autoimmune inflammation in the glomeruli.

Circulating mucosal-associated invariant T cell levels and their cytokine levels in healthy adults.

Mucosal-associated invariant T (MAIT) cells have been reported to play an antimicrobial role in infectious diseases. However, little is known about age- and gender-related changes in circulating MAIT cell level and function in healthy population. The purposes of this study were to examine the level and cytokine production of circulating MAIT cells and their subsets in healthy adults and to investigate potential relationships between clinical parameters and MAIT cell levels or their subset levels. One hundred thirty-three healthy subjects were enrolled in this study. MAIT cells, their subset, and cytokine levels were measured by flow cytometry. Circulating MAIT cell levels were found to vary widely (0.19% to 21.7%) in the study subjects and to be significantly lower in elderly subjects (age, 61-92 years) than in young subjects (age, 21-40 years) (p<0.0005). No significant difference was found in the circulating MAIT cell levels between male and female subjects. A linear regression analysis revealed that circulating MAIT cell levels declined annually by 3.2% among men and 1.8% among women, respectively. Notably, the proportion of CD4+ MAIT cells increased with age, whereas that of CD8+ MAIT cells decreased with age. In addition, the production of interleukin (IL)-4 by MAIT cells was found to be significantly increased in elderly subjects and the ratio of interferon (IFN)-γ/IL-4 was lower as compared with young subjects, showing a Th1 to Th2 shift in cytokine profile in elderly subjects. Our data suggest that aging is associated with a reduction in circulating MAIT cells, accompanied with alterations in subset composition and cytokine profile.

High CD74 expression correlates with ZAP70 expression in B cell chronic lymphocytic leukemia patients.

Chronic lymphocytic leukemia (CLL) is the most common leukemia in adults in Western countries. It is characterized by heterogeneous clinical course of the disease and new prognostic factors are still needed. CD74 plays an important role in signal transduction in B cell proliferation and survival pathway. CD74 expression has been shown in solid tumors and has been connected with poor prognosis and tumor progression. The aim of the study was to evaluate the expression of CD74 in chronic lymphocytic leukemia patients with combination with other known prognostic factors. Expression of CD74 was determined in 90 patients and 28 healthy controls. CD74 expression was significantly higher in CLL group than in controls. There was positive correlation between CD74 and ZAP70 expression (p = 0.008). High expression of CD74 was positively correlated with more advanced stage of the disease (p = 0.02). No correlation was shown between CD74 and sex, mutational status IgVH and time to first treatment.

Anti-inflammatory haemoglobin scavenging monocytes are induced following coronary artery bypass surgery.

OBJECTIVE: Circulating monocytes may counter systemic pro-inflammatory and haemolytic insults through the expression and shedding of the haemoglobin scavenger receptor (CD163). This prospective study aims to assess the effects of coronary artery bypass grafting with and without cardiopulmonary bypass (CPB) on haemoglobin scavenging and anti-inflammatory monocyte behaviour. METHODS: Forty consecutive patients underwent coronary surgery using CPB (n=20) and off-pump (n=20) techniques. Peri-operative blood samples were taken until the fifth day following surgery and statistical comparison performed to baseline using group- and subject-based analysis. Monocyte receptor expression and plasma concentrations of anti-inflammatory molecules were measured by flow cytometry and enzyme-linked immunosorbent assay, respectively. RESULTS: Monocyte CD163 expression was significantly elevated post-operatively in both surgical groups with (p=0.001) and without CPB (p=0.000) at 24-48h. By contrast, shed CD163 (p=0.02) and haemoglobin-haptoglobin complexes (p=0.000) in plasma were only significantly elevated in the on-pump group at 2-4h. Subject-based analysis demonstrated that CPB is an independent predictor of monocyte CD163 (p=0.002) and plasma sCD163 (p=0.01) concentration adjusting for the measurement timing. Significant downregulation of the monocyte major histocompatibility complex II receptor was observed in both surgical groups, whereas lipopolysaccharide receptor (CD14) expression only declined following on-pump surgery. The anti-inflammatory cytokine interleukin (IL)-10 was elevated post-operatively in both surgical groups peaking earlier in the on-pump group (2h) versus off-pump group (4h). The immunoregulatory IL-6 cytokine was significantly upregulated at 4h in both groups. CONCLUSION: Coronary artery bypass surgery induces monocyte-associated anti-inflammatory and immunoregulatory responses. There was no significant difference in haemolysis although the effect on monocyte CD163 and plasma sCD163 concentration was significantly different between the two groups. Compensation for varying pro-inflammatory and haemolytic insults may explain the differences observed. Therapeutic strategies for inducing such desirable circulating monocytes may potentially improve surgical outcome and patient recovery.