Proteomics reveals disturbances in the immune response and energy metabolism of monocytes from patients with septic shock.

Sepsis results from a dyshomeostatic response to infection, which may lead to hyper or hypoimmune states. Monocytes are central regulators of the inflammatory response, but our understanding of their role in the genesis and resolution of sepsis is still limited. Here, we report a comprehensive exploration of monocyte molecular responses in a cohort of patients with septic shock via proteomic profiling. The acute stage of septic shock was associated with an impaired inflammatory phenotype, indicated by the down-regulation of MHC class II molecules and proinflammatory cytokine pathways. Simultaneously, there was an up-regulation of glycolysis enzymes and a decrease in proteins related to the citric acid cycle and oxidative phosphorylation. On the other hand, the restoration of immunocompetence was the hallmark of recovering patients, in which an upregulation of interferon signaling pathways was a notable feature. Our results provide insights into the immunopathology of sepsis and propose that, pending future studies, immunometabolism pathway components could serve as therapeutic targets in septic patients.

The utility of second single antigen bead assay: Clearing the water or stirring up mud?

Though solid-phase single antigen bead (SAB) testing has provided major advances to the HLA community and organ allocation, it has not been without limitations. In particular, false-positive reactions lead to interpretative challenges and the potential to preclude a transplant if the corresponding antigens are deemed unacceptable. Two different vendor platforms are commercially available for SAB testing, one more recent than the other. The aim herein was to assess the benefit of using the newer SAB platform in situations where the primary platform yielded suspicious (specifically, false positive) reactions. Therefore, 42 serum samples with commonly encountered false-positive patterns observed in our laboratory were tested with the newer platform. Cases were classified as resolved, equivalent, or divergent based on whether the second platform produced no reactivity, the same pattern, or a distinctly different pattern compared to the primary platform, respectively. Approximately 33% of cases were resolved, 46% were equivalent, and 21% were divergent. The project revealed advantages of adding a second SAB platform to the laboratory's test menu including resolving challenging samples and including broader coverage of different alleles and unique class II alpha/beta subunit combinations. However, the challenges of validating, maintaining, and billing for another test method in the laboratory may be barriers to routine use.

CD4 and MHCII phenotypic variability of peripheral blood monocytes in dogs.

In humans and mice, the detailed phenotypic and functional characterization of peripheral blood monocytes allows for identification of three monocyte subsets. There are also evidences of monocyte phenotypic heterogeneity in other species, including cattle, sheep, pig and horse. However, little is known about such variability in dogs. The aim of the study was to determine whether and how peripheral blood monocytes of healthy dogs differ in the presence of MHCII and CD4 and in the basal production of reactive oxygen species (ROS). Three distinct subsets of CD11b+CD14+ monocytes were found in peripheral blood samples of healthy dogs, based on the variations in the density of MHCII and CD4 surface molecules: MHCII+CD4- (Mo1), MHCII+CD4+ (Mo2) and MHCII-CD4+ (Mo3). The Mo2 and Mo3 were significantly lower in percentage than Mo1 but their basal ROS production was higher. Within the Mo2 and Mo3 subsets, the percentage of cells producing ROS was significantly higher comparing to cells lacking this activity. Canine peripheral blood monocytes vary in the expression of MHCII and CD4 and in the activity suggesting that cells within the three identified subsets carry out different functions. The higher production of ROS in non-activated cells within small subsets of Mo2 and Mo3 monocytes might indicate their immunomodulatory potential.

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.

Getting on target: Development of the novel, prozone-resistant, dual antibody rapid test (DART) for the LABScreen single antigen bead (SAB) assay.

A major limitation of the single antigen bead (SAB) assay is the so called prozone effect, whereby the detection of high titer complement fixing HLA antibodies is compromised due to complement split product (from C3 and C4 components) deposition and interference with the reporter anti-IgG-PE antibody binding. Strategies to minimize prozone include serum titration or treatment with heat, dithiotreitol (DTT), or ethylenediaminetetraacetic acid (EDTA). While effective, these treatments may compromise HLA antibody binding and detection. Here we describe the Dual Antibody Rapid Test (DART), a modified version of the rapid optimized SAB (ROB) protocol, in which we use an IgG-PE/C3d-PE antibody cocktail to simultaneously detect bead bound IgG and C3d, which allows for detection of HLA antibodies independent of the prozone effect. Twenty prozone positive sera (10 class I and 10 class II), identified by titration, were tested by the ROB protocol, with or without EDTA pre-treatment, using three reporter antibody cocktails: (1) IgG-PE, (2) C3d-PE, or (3) IgG-PE/C3d-PE (DART). Mean fluorescence intensity (MFI) values were then compared. IgG negative (n = 735) vs IgG positive (n = 1185) reactions were identified using a 1000 MFI IgG EDTA cutoff. IgG positive reactions were classified based on ΔMFI (IgG EDTA - IgG) as follows: (1) prozone negative (ΔMFI < 3000; n = 737), (2) slight prozone (ΔMFI 3001-5000; n = 49), (3) moderate prozone (ΔMFI 5001-10,000; n = 93), and (4) marked prozone (ΔMFI > 10,001; n = 306). No C3d deposition was present on IgG negative beads, and the majority of prozone positive specificities (438/448; 98%) fixed complement and were detected with the C3d-PE reporter. Interestingly, C3d-PE MFI was directly proportional to the degree of prozone (mean C3d-PE MFI = 4419.5 ±â€¯1606.3 for slight, 5991.0 ±â€¯2302.7 for moderate, and 12,417.4 ±â€¯2969.9 for marked prozone specificities). Interestingly, EDTA treatment was found to have a negative impact on MFI of up to 15% of prozone negative specificities. Importantly, the DART protocol detected all prozone positive specificities while MFI for prozone negative specificities correlated well with those seen with the IgG-PE reporter alone (R2 = 0.97). In conclusion, the DART protocol accurately detects HLA antibodies independent of the prozone effect. Implementation of DART is an easy way to overcome the prozone effect without compromising HLA antibody detection.

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.

Invariant chain p41 mediates production of soluble MHC class II molecules.

Major histocompatibility complex class II (MHC II) molecules are mainly expressed on antigen presentation cells and play an important role in immune response. It has been reported that MHC II molecules are also detected in serum as a soluble form (sMHC II molecules), and they are considered to be involved in the maintenance of self-tolerance. However, the mechanism by which sMHC II molecules are produced remains unclear. Invariant chain (Ii), also called CD74, plays an important role in antigen presentation of MHC II molecules. In the present study, we analyzed the role of Ii on the production of sMHC II molecules. We found that the amount of sMHC II molecules in serum was decreased in Ii-deficient mice compared to wild-type mice. sMHC II molecules were secreted from cells transfected with MHC II molecules and Ii but not from cells transfected with MHC II molecules alone. Moreover, isoform p41 of Ii-transfected cells induced more sMHC II molecules compared to isoform p31-transfected cells. The molecular weight of sMHC II molecules from MHC II and Ii p41-transfected cells was approximately 60 kDa, indicating that sMHC II molecules are a single heterodimer of α and ß chains that is not associated with micro-vesicles. From the analysis of Ii-deletion mutants, we found that the luminal domain of Ii p41 is crucial for the production of sMHC II molecules. These results suggested that Ii has an important role in production of sMHC II molecules.

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.

Dynamics of humoral response in naturally-infected cattle after vaccination against leptospirosis.

Vaccination is one of the most important measures for the control of bovine leptospirosis. Despite the broad usage of vaccination against leptospirosis in cattle worldwide, the dynamics of the post-vaccine immune response remain controversial and many aspects are still unclear, particularly in naturally-infected animals. Thus, the objective of this study is to describe the dynamics of humoral response in naturally-infected cattle after vaccination against leptospirosis. A total of 162 cows were studied, consisting of 129 included in the experimental group (G1), and subdivided into two groups, vaccinated with two different brands of bacterins, as well as 33 in the control group (G2). Serology (MAT) was performed in all cows on D0 (vaccination), then 60 and 120 days post-vaccination. Vaccination significantly elicited the production of anti-leptospiral antibodies. Seroreactivity increased rapidly but was of short duration (up to D60). Significantly, that increase was notably higher in the vaccinated group than in the controlled. Both vaccines elicited a similar response with a higher rate of seroreactive animals, but predominately against different serogroups. In this context, our results reinforce that, although of limited duration, vaccination against leptospirosis significantly elicits a specific humoral response in naturally-infected animals. The two studied vaccines presented similar seroconversion levels, but predominantly to different serogroups, being one against Icterohaemorrhagiae and the other against Sejroe.

MIF/CD74 axis is a target for metformin therapy in diabetic podocytopathy - real world evidence.

Introduction：To observe the effects of metformin on urinary excretion of MIF, CD74 and podocalyxin in type 2 diabetics and to explore its possible renoprotective mechanisms. METHODS: 202 uncontrolled type 2 diabetics, who were previously prescribed sulfonylurea monotherapy(n=100) or sulfonylurea in combination with metformin (n=102) were enrolled in the study. The amount of macrophage migration inhibitory factor(MIF) and CD74 in serum, urinary MIF to creatine ratio(UMCR), urinary CD74 to creatine ratio(UCCR), urinary albumin to creatine ratio(UACR) and urinary podocalyxin to creatine ratio (UPCR) were determined. RESULTS: Metabolic parameters including fasting blood glucose, postprandial 2 hours blood glucose, hemoglobin A1c, MIF and CD74 in serum were comparable between the two groups. Moreover, metformin add-on therapy showed significantly better efficacy in reducing UMCR, UCCR, UPCR and UACR in comparison with those in sulfonylurea monotherapy group, respectively. UPCR had positive correlation with UACR, UMCR and UCCR (r＝0.73, r=0.69, r=0.62, P < 0.01), respectively. CONCLUSIONS: Metformin could present its podocyte-protective capacity in type 2 diabetics and the underlying mechanisms may be partly attributed to its effects in suppressing MIF-CD74 axis mediated inflammatory cascade response. < p > < /p >.

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.

Soluble HLA-I and HLA-II Molecules Are Potential Prognostic Markers of Progression of Systemic and Local Inflammation in Patients with COPD.

Soluble molecules of the major histocompatibility complex play an important role in the development of various immune-mediated diseases. However, there is not much information on the participation of these proteins in the pathogenesis of chronic obstructive pulmonary disease (COPD). The aim of our work was to determine the content of soluble molecules of the major histocompatibility complex of classes I and II (sHLA-I and sHLA-II) in the exhaled breath condensate (EBC) and in the blood serum in patients with moderate to severe COPD during the exacerbation and stable phase. We investigated 105 patients (male) with COPD aged 46-67 and 21 healthy nonsmoking volunteers (male) comparable in age. The content of sHLA-I and sHLA-II molecules was studied using ELISA. We found an increase in the level of sHLA-I and sHLA-II molecules in EBC, as well as an enhancement in the serum content of sHLA-II in all the examined COPD patients compared to healthy nonsmoking volunteers. The revealed negative correlation between the serum concentration of sHLA-II and values of FEV1 and FEV1/FVC in all examined patients with COPD gives a possibility to consider the content of these proteins as an additional systemic marker of disease severity. The maximum endobronchial and serum concentrations of sHLA-I and sHLA-II were detected in patients with severe COPD during the exacerbation. The negative associations between the content of these molecules in EBC and serum and the parameters of lung function in patients with severe COPD were established. These findings suggest a pathogenetic role of sHLA-I and sHLA-II molecules in the mechanisms of the development and progression of local and systemic inflammation in COPD.

Nomenclature and Serology of HLA Class I and Class II Alleles.

This overview presents nomenclature and serology information on human leucocyte antigens, or HLA molecules, which are encoded by a cluster of genes linked on the short arm of chromosome 6. This region is known as the major histocompatibility complex and codes for class I and class II molecules, which are distinguished from each other based upon their structure, tissue distribution, and source of peptide antigen, as well as upon their interactions with T cell subsets. © 2017 by John Wiley & Sons, Inc.

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.

Association between mRNA expression of CD74 and IL10 and risk of ICU-acquired infections: a multicenter cohort study.

PURPOSE: Intensive care unit (ICU)-acquired infections (IAI) result in increased hospital and ICU stay, costs and mortality. To date, no biomarker has shown sufficient evidence and ease of application in clinical routine for the identification of patients at risk of IAI. We evaluated the association of the systemic mRNA expression of two host response biomarkers, CD74 and IL10, with IAI occurrence in a large cohort of ICU patients. METHODS: ICU patients were prospectively enrolled in a multicenter cohort study. Whole blood was collected on the day of admission (D1) and on day 3 (D3) and day 6 (D6) after admission. Patients were screened daily for IAI occurrence and data were censored after IAI diagnosis. mRNA expression levels of biomarkers were measured using RT-qPCR. Fine and Gray competing risk models were used to assess the association between gene expression and IAI occurrence. RESULTS: A total of 725 patients were analyzed. At least one IAI episode occurred in 137 patients (19%). After adjustment for shock and sepsis status at admission, CD74 and IL10 levels were found to be significantly associated with IAI occurrence [subdistribution hazard ratio (95% confidence interval) 0.67 (0.46-0.97) for CD74 D3/D1 expression ratio and 2.21 (1.63-3.00) for IL10 at D3]. IAI cumulative incidence was significantly different between groups stratified according to CD74 or IL10 expression (Gray tests p < 0.001). CONCLUSION: Our results suggest that two immune biomarkers, CD74 and IL10, could be relevant tools for the identification of IAI risk in ICU patients.

Upregulation of CD74 and its potential association with disease severity in subjects with ischemic stroke.

Macrophage migration inhibitory factor (MIF) is a key cytokine/chemokine in the activation and recruitment of inflammatory T lymphocytes known to exacerbate experimental stroke severity. MIF effects are mediated through its primary cellular receptor, CD74, the MHC class II invariant chain present on all class II expressing cells, including monocytes, macrophages and dendritic cells (DC). We demonstrated previously that partial MHC class II/peptide constructs (pMHC) can effectively treat mice with experimental stroke, in part through their ability to competitively inhibit MIF/CD74 interactions and downstream signaling. However, the role of MIF and CD74 in human ischemic stroke is not yet well established. To evaluate the therapeutic potential for pMHC, we assessed MIF and CD74 expression levels and their association with disease outcome in subjects with ischemic stroke. MIF levels were assessed in blood plasma by ELISA and CD74 expression was quantified by flow cytometry and qRT-PCR in peripheral blood mononuclear cells (PBMCs) obtained from subjects with ischemic stroke and age and sex-matched healthy controls (HC). MIF levels were increased in plasma and the number of CD74+ cells and CD74 mRNA expression levels were significantly increased in PBMC of subjects with ischemic stroke versus HC, mainly on CD4+ T cells, monocytes and DC. Greater increases of CD74+ cells were seen in subjects with cortical vs. subcortical infarcts and the number of CD74+ cells in blood correlated strongly with infarct size and neurological outcomes. However, differences in MIF and CD74 expression were not affected by age, gender or lesion laterality. Increased CD74 expression levels may serve as a useful biomarker for worse stroke severity and predicted outcomes in subjects with ischemic stroke and provide a rationale for potential future treatment with pMHC constructs.

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.