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Pretransplant immunological assessment of a transplant donor has evolved significantly over the last few decades with the advent of testing platforms with enhanced sensitivity and varying formats. The single antigen bead assay (SAB) assay, a virtual crossmatch (vXM) is used extensively and considered the gold standard for defining donorspecific antibodies (DSA) in many parts of the World. A country like India, is however challenged by the lack of adequate representation of locally frequent HLA alleles and hence in our institution, we continue to perform a physical crossmatch (pXM) on the Complement Dependent Cytotoxicity and flow cytometry platforms alongside the SAB. We report here a case report where the discrepancy between platforms of testing have raised certain pertinent questions in our interpretation of the vXM. [ABSTRACT FROM AUTHOR]

Background: The main objective of this study was to determine the results of the cell-based assay (CDC-XM and FC-XM), and correlate with the results of solid phase assay (L-SAB). Methods. In this retrospective study, 350 prospective renal transplant recipients were tested for the presence of HLA antibodies by CDC-XM, FC-XM and L-SAB screening with their corresponding donor. Results: T-cell-FC-XM showed a sensitivity of 71.43% and a specificity of 91.50% for detecting class I L-SAB (+), while B-cell-FCXM showed a sensitivity of 94.94% and a specificity of 61.99% for detecting class II L-SAB (t). On the other hand, T-CDC-XM showed a sensitivity of 32.14% and a specificity of 98.64% for detecting class I L-SAB (-4-), while B-CDC-XM showed a sensitivity of 44.30% and a specificity of 94.83% for detecting class H L-SAB (-). In this study, the results indicated that DSA class I MFI value of 2845 and above significantly (p 50.001) correlated with T-cell-FC-XM positivity, while MFI value of 4585 and above (p 50.001) showed strong predictive accuracy of a positive T-cell-CDC-XM. However, DSA class II MFI cut-off of 1988 and above significantly (p 50.001) correlated with B-cell-FC-XM positivity, while MFI value of 5986 and above (p %0.001) showed strong predictive accuracy of a positive B-cell-CDC-XM. Conclusions: Our study showed that CDC-XM has poor sensitivity, while FC-XM has poor specificity to detect DSA. L-SAB has good correlation with T-cell-FC-XM (p < 0.0001) but not with B-cell-FC-XM (P = 0.31). DSA strength >2845 and > 1988 significantly correlated with T-cell-FC-XM positivity and B-cell-FC-XM positivity, respectively. While, a MFI value of >4585 and > 5986 significantly correlated with T-tell-CDC-XM posilivity and Bcell- CDC-XM positivity, respectively. These MFI cut-off values could serve as a surrogate marker for CDC-XMl and FC-XM tests and may help in resolving the limitations of cell-based techniques. Iii conclusion, we found that LSAB is more sensitive and specific than CDC-XM and FC-XM and therefore may be used as a test of choice. [ABSTRACT FROM AUTHOR]

Background Patients awaiting solid organ transplantation may develop anti-HLA antibodies after sensitization events such as transfusions, pregnancies, or previous transplantations. However, the effects of a particular sensitization event on HLA alloimmunization have not been well studied in parallel using cell-based assays and solid-phase assays. In this study, we evaluated and compare how different sensitization events affect the HLA antibody screening (HLA-Ab) and donor specific antibody (DSA) status in solid renal organ transplantation patients. Methods HLA antibody (HLA-Ab) screening tests like complement-dependent cytotoxicity crossmatch (CDC-XM), flow cytometry crossmatch (FC-XM) and Luminex panel-reactive antibody (L-PRA) were performed in all 1066 patients (635 males and 431 females). If any of these tests turned out to be positive, a Luminex single antigen bead (L-SAB) assay was performed for DSA identification. Test positive rates and antibody strengths were analyzed according to the different sensitization events and gender. Results In this study, HLA-Ab screening tests positive rates (L-PRA, FC-XM and CDC-XM) were significantly higher in patients with previous transplantation (73.91%, 100% and 56.52% p < 0.001), previous pregnancy (57.46%, 70.14% and 18.85% p < 0.001) or blood transfusion (27.33%, 35.55% and 7.33% p < 0.001) compared with patients without a sensitizing event (6.17%, 13.58% and 1.09). In this study, re-transplantation group showed significantly stronger antibody strength (DSA) than non sensitized group (class I and II MFI 11418.04, 17,837.78 vs class I and II MFI 2659, 3329; P < 0.001) and those with single sensitization events of transfusion (class I and II MFI 11418.04, 17,837.78 vs class I and II MFI 5790.26, 6004.16; P < 0.001) or pregnancy (class I & II MFI 11418, 17,837 vs class I and II MFI 8631.71, 7253.29; P < 0.001). Conclusions Pregnancy and blood transfused had high allo-immunization rate for class I HLA antigens. While re-transplantation patients had high allo-immunization rate for both the HLA classes (HLA- class I and HLA- class II). Re-transplantation group showed significantly stronger antibody strength, followed by pregnancy and then transfusion. [ABSTRACT FROM AUTHOR]

It is still not fully elucidated which pretransplant donor‐specific HLA antibodies (DSA) are harmful after kidney transplantation. In particular, it needs to be clarified whether cumulative mean fluorescence intensities (MFI) against multiple HLA specificities have a predictive value for allograft function. Our retrospective single centre study analyzed preformed HLA antibodies determined by Luminex™ Single Antigen Bead (SAB) assay, including C1q addition, in relation to rejection and clinical outcome in 255 cross match negative kidney allograft recipients. Only 33 recipients (13%) of the total cohort showed early AMR during the first year posttransplant, but in patients with pre‐transplant DSA the rate was increased to 15 out of 40 (38%). Three year graft survival was significantly shorter in patients with histological signs of AMR compared with patients without AMR or with no biopsy (74%, 92%, and 97%, respectively, p < 0.0001). In patients with HLA‐DSA, a cumulative MFI value of all HLA antibodies of more than 103.000 indicated the highest risk for AMR posttransplant (p = 0.01). In conclusion, in patients with HLA‐DSA, the cumulative MFI value may help to further stratify the risk of AMR after kidney transplantation. [ABSTRACT FROM AUTHOR]

Introduction: Cell-based complement-dependent cytotoxicity crossmatch (CDC-XM) and solid phase assays were introduced for assessing HLA antibodies. However, the complexity of data from cell-based and solid phase assays have led to potential confusion about how to use the results for clinical decision making. Aim: Aim of this study was to compare results of cell-based assay and solid phase assay, to evaluate the usefulness of L-XM for pretransplant detection of HLA class I and II donor-specific IgG antibodies, correlate the mean fluorescence intensity (MFI) values of class I and class II L-XM assay and with CDC-XM and L-PRA (panel reactive antibodies) results. Methods: In this retrospective study, 380 prospective renal transplant recipients were tested for the presence of HLA antibodies by CDC-XM, IgG-L-XM, IgG-L-PRA & L-SAB screening with their corresponding donor. Results: Fifty-one recipients (13.42%) had a positive CDC-XM. L-XM was positive in 125 recipients (32.89%); class I-L-XM was positive in 46 (36.80%) cases, and class II-L-XM was positive in 58 (46.4%) cases and 21 (16.8%) samples were positive for class I and class II. High background was present in 22 (5.87%) samples, the results of which were confirmed by retesting or by correlation with L-PRA and L-SAB assays. Conclusion: The introduction of more sensitive approaches for the detection of anti-HLA-IgG-antibodies, such as L-XM and L-PRA assay, has allowed the identification of anti-HLA-antibodies in recipient serum which is not usually identified by CDC-XM alone. However, L-XM has some limitations; they can be overcome if we combine this assay with L-PRA. [ABSTRACT FROM AUTHOR]

We demonstrate the prognostic utility of antigen quantitation in chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) and monoclonal B-cell lymphocytosis (MBL). Median antibody-bound-per-cell (ABC) of CD20, CD22, CD25, CD19, and %CD38(+) was determined in CLL (185/208), SLL (8/208) and MBL (15/208) cases by flow cytometry, then compared to Dohner-classification, immunoglobulin status (mutated, IGHV-M; unmutated, IGHV-U), CLL-IPI risk and time to first treatment (TTFT). Trisomy 12 cases showed increased %CD38-expression (p =.0379). Higher %CD38 was observed in IGHV-U versus IGHV-M (p =.0003). CD20ABC was increased in IGHV-U versus IGHV-M (p =.006). Del13q cases demonstrated lower CD22ABC (p =.0198). Cases without cytogenetic abnormality exhibited higher CD19ABC (p =.0295) and CD22ABC (p =.0078). Del17p cases demonstrated lower CD25ABC (p =.0097). High and very-high CLL-IPI risk groups were associated with high CD38-expression (p =.02) and low CD25ABC (p =.0004). Shortened TTFT was associated with high CD38-expression (p <.0001). Interestingly, high CD25ABC trended toward shortened TTFT (p =.07). Quantitative antigen expression reflects CLL-IPI risk groups and Dohner-classification. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare the results of solid phase assay and cell-based assay, and explore the near-accurate DSA-MFI-cutoff value detected on solid phase assay above which the cell-based assay would show a positive result. In this retrospective study, 102 prospective renal transplant recipients were tested for the presence of donor-specific antibodies (DSAs) by cell-based assay (T-cell-CDC-AHG-XM and T-cell-IgG-FC-XM) and solid phase assay (class-I-IgG-L-SAB) with their corresponding donor. Among the 40 patients in the group first (L-SAB-DSA-MFI<1000), one case was positive in IgG-T-cell-FC-XM while T-cell-CDC-AHG-XM was negative in all the cases. In the second group having L-SAB-DSA-MFI values between 1000 and 3000, 19 cases were positive and the remaining 11 cases were negative in IgG-T-cell-FC-XM. T-cell-CDC-AHG-XM showed a negative reaction in all 30 cases. In the third group having L-SAB-DSA-MFI values between 3000 and 5000, IgG-T-cell-FC-XM was positive in 18 cases while, two were negative. T-cell-CDC-AHG-XM demonstrated a negative result in 14 cases while reaming six cases demonstrated a positive result. In the fourth group having L-SAB-DSA-MFI values >5000, all 12 cases showed a positive result in both IgG-T-cell FC-XM and T-cell-CDC-AHG-XM. Our results indicated that the L-SAB-DSA-MFI values >2215 were significantly (P <.001) correlated with positive IgG-T-cell-FC-XM while L-SAB-DSA-MFI values >4689 were significantly (P <.001) correlated with positive CDC-XM. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the mean fluorescence intensity (MFI) values of class II Luminex single antigen bead (L-SAB) assay and compare these MFI values with cell-based complement-dependent cytotoxicity crossmatch with anti-human globulin (CDC-AHG-XM) and IgG-B-cell flow cytometry crossmatch (FC-XM) results and explore the near-accurate MFI-cutoff values of positive cell-based crossmatch results. This retrospective study was an analysis in 97 renal transplant recipients, who were tested for the presence of DSA by CDC-AHG-XM and IgG-B-cell-FC-XM methods with their corresponding donor as well as for anti-human leukocyte antigen (HLA) antibody detection using a sensitive L-SAB assay. In the group having DSA MFI values <1000, none of the patients showed positivity for FC-XM and CDC-AHG-XM; in the group having MFI values between 1000 and 3000, 35.48% showed positivity for FC-XM but none by the CDC-AHG-XM method. However, in the group having MFI values >3000, 83.33% of cases were positive for FC-XM. Further, in those groups with MFI values between 3000 and 6000, 38.09% were positive for CDC-AHG-XM, while 86.66% showed positivity in the group with MFI >6000. Our results indicated that Luminex-DSA MFI value >1995 (P <.0001) significantly correlated with IgG-B-cell-FC-XM positivity while Luminex-DSA MFI value of >4247 (P <.0006) was significantly correlated with positive CDC-AHG-XM. MFI cutoff of 1995 exhibited a diagnostic sensitivity of 97.56% and specificity of 89.29% for predicting positive IgG B-cell FC-XM and MFI cutoff of 4247 exhibited a diagnostic sensitivity of 90.48% and specificity of 97.37% for predicting positive CDC-AHG-XM. However, a cutoff MFI of >5000 and >7000 for SAB assay had a sensitivity and specificity of 100% in detecting a positive IgG B-cell FC-XM and CDC-AHG-XM, respectively. [ABSTRACT FROM AUTHOR]

In diffuse large B-cell lymphoma, bone marrow involvement is rarely diagnosed. We compared the properties of bone marrow stromal progenitor cells and the concentration of fibroblast CFU in patients with diffuse large B-cell lymphoma without bone marrow involvement and in healthy donors. It was found that the properties of multipotent mesenchymal stromal cells in patients in the debut of the disease differed considerably from those in healthy donors. In particular, the total cell production in patients was significantly higher than in donors. In multipotent mesenchymal stromal cells of patients, some cell parameters were changes; the mean fluorescence intensity of the adhesion molecule ICAM1 on the cell surface was increased. The mean fluorescence intensity of mesenchymal stromal cell markers (HLA-ABC, CD73 and CD90) was significantly elevated. The relative expression of BMP4, MMP2, FGFR1, and ICAM1 genes in mesenchymal stromal cell was reduced, while the expression of FGFR2 gene was enhanced. Despite the absence of proven involvement of the bone marrow, the properties of mesenchymal stromal cells, the components in the stromal microenvironment niche regulating hemopoiesis are altered in patients with diffuse large B-cell lymphoma. [ABSTRACT FROM AUTHOR]

In diffuse large B-cell lymphoma, bone marrow involvement is rarely diagnosed. We compared the properties of bone marrow stromal progenitor cells and the concentration of fibroblast CFU in patients with diffuse large B-cell lymphoma without bone marrow involvement and in healthy donors. It was found that the properties of multipotent mesenchymal stromal cells in patients in the debut of the disease differed considerably from those in healthy donors. In particular, the total cell production in patients was significantly higher than in donors. In multipotent mesenchymal stromal cells of patients, some cell parameters were changes; the mean fluorescence intensity of the adhesion molecule ICAM1 on the cell surface was increased. The mean fluorescence intensity of mesenchymal stromal cell markers (HLA-ABC, CD73 and CD90) was significantly elevated. The relative expression of BMP4, MMP2, FGFR1, and ICAM1 genes in mesenchymal stromal cell was reduced, while the expression of FGFR2 gene was enhanced. Despite the absence of proven involvement of the bone marrow, the properties of mesenchymal stromal cells, the components in the stromal microenvironment niche regulating hemopoiesis are altered in patients with diffuse large B-cell lymphoma. [ABSTRACT FROM AUTHOR]

In this retrospective study, our aim was to find the effect of leucodepleted (LD) blood transfusions on the formation of anti-HLA-antibodies when compared to non-leucodepleted (non-LD) transfusions using Luminex-based method. In this study, Luminex single antigen bead assay (L-SAB) and HLA typing were performed on 310 patients. Test positivity rates (as MFI - Mean florescence intensity) were analyzed according to the different sensitization events and gender. Of the 310 patients included in the study, 58.06% (180) patients were male and 41.93% (130) were female. The average age of the patients was 42.86 (±12.37) years. In this study, test positivity rates were significantly lower in the patients who received LD RBC units than in those who received non-LD RBC units (28.43% = 29 of 102 Vs 55.22% = 74 of 134, p < 0.05). In our study, transfusion combined with a history of pregnancy had higher number of significant HLA antibodies compared to cases where transfusion was the only sensitization event (81.81% = 18/22 Vs 39.71% = 85/214, p < 0.05). In addition, anti-HLA-antibodies-MFI were significantly (p < 0.01) higher in non-LD patients compared to LD patients. Patients who received LD RBC units had a significantly lower rate of transfusion-associated alloimmunization compared to those who received non-LD RBC units. Multiparous women had a high risk for transfusion-related alloimmunization compared to both nulliparous women and male patient. Furthermore, class I-anti-HLA-antibodies (HLA-B and HLA-A + B) were significantly associated with pregnancy sensitization and/or blood transfusion as a single sensitization. [ABSTRACT FROM AUTHOR]

Background: Tumor proliferation often occurs from pathologic receptor upregulation. These receptors provide unique targets for near-infrared (NIR) probes that have fluorescence-guided surgery (FGS) applications. We demonstrate the use of three smart-targeted probes in a model of head and neck squamous cell carcinoma. Methods: A dose escalation study was performed using IntegriSense750, ProSense750EX, and ProSense750FAST in mice (n = 5) bearing luciferase-positive SCC-1 flank xenograft tumors. Whole body fluorescence imaging was performed serially after intravenous injection using commercially available open-field (LUNA, Novadaq, Canada) and closed-field NIR systems (Pearl, LI-COR, Lincoln, NE). An ex vivo, whole-body biodistribution was conducted. Lastly, FGS was performed with IntegriSense750 to demonstrate orthotopic and metastatic disease localization. Results: Disease fluorescence delineation was assessed by tumor-to-background fluorescence ratios (TBR). Peak TBR values were 3.3 for 1 nmol ProSense750EX, 5.5 for 6 nmol ProSense750FAST, and 10.8 for 4 nmol IntegriSense750 at 5.5, 3, and 4 d post administration, respectively. Agent utility is unique: ProSense750FAST provides sufficient contrast quickly (TBR: 1.5, 3 h) while IntegriSense750 produces strong (TBR: 10.8) contrast with extended administration-to-resection time (96 h). IntegriSense750 correctly identified all diseased nodes in situ during exploratory surgeries. Ex vivo, whole-body biodistribution was assessed by tumor-to-tissue fluorescence ratios (TTR). Agents provided sufficient fluorescence contrast to discriminate disease from background, TTR>1. IntegriSense750 was most robust in neural tissue (TTR: 64) while ProSense750EX was superior localizing disease against lung tissue (TBR: 13). Conclusion: All three agents appear effective for FGS. [ABSTRACT FROM AUTHOR]

Objective: The aim of our study was the optimization and standardization of intracellular dedicator of cytokinesis 8 (DOCK8), LPS-responsive beige-like anchor protein (LRBA), SH2D1A/SLAMassociated protein (SAP) and X-linked inhibitor of apoptosis protein (XIAP) protein expressions in healthy controls with a single flow cytometer protocol and to concomitantly evaluate the possible use of this method for diagnosis. Materials and Methods: Peripheral blood mononuclear cells were isolated from heparinized blood samples. Protein expressions were analyzed as mean fluorescein intensity difference (ΔMFI) according to the isotype. Results: ΔMFI values obtained by DOCK8 antibody staining were 21.3±4 in CD3+ T cells and 25±3.3 in CD20+ T cells in healthy controls. These values in patients with DOCK8 deficiency were either very low or completely absent. ΔMFI values obtained by LRBA protein antibody staining were 36±7.7 in healthy controls, while they were at the very low levels of 5.9±1.8 in the LRBA protein deficiency patients. The values obtained by SAP and XIAP antibody staining were 30.2±3 in CD8+ T cells for SAP, 13.9±3.2 in CD3+ T and 14.6±3.5 in CD20+ B cells for XIAP. Since the SAP and XIAP results were not confirmed by gene sequencing, the results were not compared to healthy controls. Conclusion: Due to its rapid and reliable results in clinically relevant cases for DOCK8 and LRBA deficiencies, analysis of protein expression is primarily suitable to evaluate intracellular staining protocol by flow cytometer. In addition, this particular method could be suitable for patients considered to be SAP and XIAP deficient. [ABSTRACT FROM AUTHOR]

The significance of pretransplant anti-human leukocyte antigen antibody levels that are detectable by more sensitive platforms (including the Luminex platform) yet undetected by complement-dependent cytotoxicity (CDC) assay remains unclear. The aim of this study was to determine the clinical significance of the donor-specific antibody (DSA) assay Luminex crossmatch and its impact on short-term renal graft outcome such as acute rejections, graft survival, and graft function. The results of pretransplant DSA-lymphocyte crossmatching (LCXM) assay in 126 renal allograft recipients whose CDCs crossmatches were negative were retrospectively analyzed for correlation with posttransplant outcomes. Of the 126 recipients, 32 (25.4%) had pretransplant DSA positive. Statistically significant association was found between DSA-LCXM positivity with 14th day estimated glomerular filtration rate (eGFR) (P = 0.05), DSA Class I with 3rd (P = 0.014) and 6th month (P = 0.02) eGFR, DSA Class II with 14th day (P = 0.06) and 1st month (P = 0.10) eGFR, mean fluorescent intensity (MFI) DSA with 7th day (P = 0.08) and 14th day (P = 0.09) eGFR, and maximum MFI DSA with 7th day eGFR (P = 0.09). The posttransplant eGFR was higher at various time intervals in DSA-LCXM-negative patients as compared to DSA-positive patients. However, pretransplant DSA-LCXM results did not predict the rejection episodes, graft loss, and 1-year posttransplant 24 h urine protein. Pretransplant DSA detected by LCXM in patients with a negative CDC does not predict adverse short-term outcomes. However, the difference in posttransplant eGFR supports further investigation in long-term effects. [ABSTRACT FROM AUTHOR]

Background & objectives: Antibodies specific to donor human leucocyte antigen (HLA) play a critical role in graft rejection and graft loss. In recent years, techniques for their detection have evolved significantly providing an ever-increasing degree of sensitivity and specificity, from the conventional cell-based assays to the advanced solid-phase system based on the Luminex platform. Consensus is still evolving on the routine employment of all these methods, either stand alone or in combination. The objective of this study was to explore the near-accurate mean fluorescence intensity (MFI) cut-off values detected on Luminex platform predicting the strength of cell-based crossmatch results. Methods: Serum samples from 116 primary renal transplant recipients awaiting transplantation were tested for the presence of antidonor antibodies by the complement-dependent cytotoxicity (CDC) and flow crossmatch (FCXM) methods with their corresponding donors as well as for HLA-donor-specific antibodies (DSA) detection using a sensitive single antigen bead (SAB) assay. Results: None of the patients having HLA Class I DSA with MFI values <1000 showed positivity for T-cell FCXM or CDC crossmatch, while in the group having MFI values between 1000 and 3000, 54 per cent showed positivity for the FCXM but none by the CDC method. However, in the group having MFI values >3000, 95 per cent of cases were positive for FCXM. Further, those groups with MFI values between 3000 and 5000, only 36 per cent were positive for CDC crossmatch, while 90 per cent showed positivity in the group with MFI >7000. Interpretation & conclusions: A cut-off MFI value of 3000 for Luminex SAB-based assay was found to significantly correlate with the FCXM positivity while a MFI value of 7000 and above predicted a positive CDC crossmatch. MFI cut-off value obtained as a surrogate marker for CDC and FCXM tests will help in resolving the limitations of different cell-based techniques. [ABSTRACT FROM AUTHOR]

Green fluorescent protein produces significant fluorescence and is extremely stable, however its excitation maximum is close to the ultraviolet range and thus can damage living cells. Hence, Leishmania donovani stably expressing DsRed were developed and their suitability for flow cytometry-based antileishmanial screening was assessed by evaluating the efficacies of standard drugs as well as newly synthesised chalcone thiazolyl-hydrazone compounds. The DsRed gene was successfully integrated at the 18S rRNA locus of L. donovani and transfectants (LdDsRed) were selected using hygromycin B. Enhanced expression of DsRed and a high level of infectivity to J774A.1 macrophages were achieved, which was confirmed by fluorescence microscopy and flow cytometry. Furthermore, these LdDsRed transfectants were utilised for development of an in vitro screening assay using the standard antileishmanial drugs miltefosine, amphotericin B, pentamidine and paromomycin. The response of transfectants to standard drugs correlated well with previous reports. Subsequently, the suitability of this system was further assessed by screening a series of 18 newly synthesised chalcone thiazolyl-hydrazone compounds in vitro for their antileishmanial activity, wherein 8 compounds showed moderate antileishmanial activity. The most active compound 5g , with ca. 73% splenic parasite reduction, exerted its activity via generating nitric oxide and reactive oxygen species and inducing apoptosis in LdDsRed - infected macrophages. Thus, these observations established the applicability of LdDsRed transfectants for flow cytometry-based antileishmanial screening. Further efforts aimed at establishing a high-throughput screening assay and determining the in vivo screening of potential antileishmanial leads are required. [ABSTRACT FROM AUTHOR]

Background: Chronic rhinosinusitis with nasal polyps (CRSwNP) is associated with Th2-dominant inflammation. However, effective treatments for CRSwNP have not yet been found. This study aimed to investigate the expression of Orai1 in nasal polyps (NP) and the influence on them of the intervention of Ca2+ release-activated Ca2+ (CRAC) channels. Materials and Methods: Nasal samples were obtained from normal subjects or subjects with CRSwNP. We studied the distribution of Orai1 protein in NP and normal mucosa (normal group) using immunohistochemistry. These tissues in cultures were then maintained in the absence (control group) or presence of 2-aminoethoxydiphenyl borate (2-APB) for 24 h. Orai1 was examined by means of enzyme-linked immunosorbent assay (ELISA) and real-time reverse transcription-polymerase chain reaction (RT-PCR). The Ca2+ mean fluorescence intensity (MFI) was evaluated by flow cytometry, and the inflammatory mediators, including interleukin (IL)-4, IL-5, IL-13, Dermatophagoides pteronyssinus-specific IgE, leukotriene C4 and eosinophil cation protein in cultures, were analyzed with ELISA and real-time RT-PCR. Results: The expression of Orai1 was localized to the cytoplasmic membrane of inflammatory cells, and upregulated in NP compared to that in the normal group. However, Orai1 protein was decreased in polyp tissues after the 2-APB treatment. The levels of Ca2+ MFI and above inflammatory mediators were also elevated in NP, and reduced after the 2-APB administration compared to those in the control group. Conclusions: Orai1 and CRAC channels may play a crucial role in NP formation and development, and the 2-APB intervention of Orai1 protein may alleviate inflammatory responses in NP. © 2015 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Objectives: The prognostic impact of immunophenotypic markers in acute myeloid leukemia (AML) is controversial. Methods: We retrospectively analyzed the value of CD34, CD117, CD7, and CD123 expression in a consecutive series of 592 adult patients with de novo AML. Results: CD34+ measured as a percentage (≥2.88%) and CD34 mean fluorescence intensity (MFI) (≥146.79, arbitrary units [AU]) expression had a prognostic impact in terms of overall survival (OS; P = .005, P = .003), leukemia-free survival (LFS; P = .011, P < .001), and cumulative incidence of relapse (CIR; P = .014, P =. 001). The percentage of CD117+ cells (61.29%) was associated with shorter LFS (P =. 043), and CD117 MFI (≥284.01 AU) was associated with a shorter OS (P =. 033) and LFS (P =. 028). In the multivariate analysis, high CD34 MFI retained the independent value as predictor of LFS and CIR (P =. 012; hazard ratio [HR], 1.59; 95% confidence interval [CI], 1.11- 2.28 and P =. 045; HR, 1.58; 95% CI, 1.01-2.46). Conclusions: CD34 positivity threshold with prognostic relevance is low (3% positive cells). Immunophenotypic findings in AML probably could only be fully exploited after a complex analysis that takes into account unconventional thresholds and the MFI. [ABSTRACT FROM AUTHOR]

Recently, management of patients awaiting solid organ transplantation has taken advantages after the development of more sensitive and accurate solid phase assays which have supported the historic complement dependent cytotoxicity. This approach has allowed the detection of antibodies in patients previously considered negative. The use of the single antigen beads resulted in a more accurate anti-human leukocyte antigen (HLA) antibody characterization. The detection of anti-HLA antibodies specific for C, DQ and DP loci that were not so well characterized has been possible through the implementation of the single antigen assay. The assessment of HLA compatibility has been expanded through the introduction of “epitope matching” concept and the definition of the unacceptable antigens for a more adequate evaluation of donor-recipient compatibility. However, the clinical impact of pre-formed and de novo anti-HLA antibodies detected by solid phase assays is still controversial due to the drawback related to result interpretation. Until today, the unresolved issues concern if all antibodies affect the medium and long term clinical outcome. An open debate on the clinical relevance of anti-HLA antibodies detected by single-antigen beads highlights needing to further investigations. Here, we describe the novel applications and the improvements of the solid-phase assay use. [ABSTRACT FROM AUTHOR]

Problem Dendritic cells ( DCs) play an important role in maintaining pregnancy by inducing tolerance toward the fetus. Such an immunologic change in the mother should be restored to normal after delivery, but few studies have reported postpartum maternal immune recovery, in terms of the types circulating DCs. Method of study The level of each DC subtype and HLA- DR-positive immunoreactivity of the blood from 29 pregnant women with uncomplicated labor was serially analyzed by flowcytometry at delivery and at 1.5, 6, and 12 months after delivery. DC subtypes were characterized as myeloid, lymphoid, and less differentiated (ld DC). Mean fluorescence intensity ( MFI) was evaluated for HLA- DR expression for each DC subtype. Results The total number and the percentage of DCs at delivery were lower than those at 12 months postpartum. The ld DC fractions were significantly higher at delivery and at 1.5 months than at 12 months postpartum. The MFI of HLA- DR expression on ld DCs at delivery was lower than that at 12 months postpartum. The myeloid-to-lymphoid DC ratio did not differ over the 1-year postpartum period. Conclusion The maternal alteration in DCs rapidly normalized within 1.5 months, except for the ld DC fraction, which persisted between 1.5 and 6 months after delivery. [ABSTRACT FROM AUTHOR]

The aim of this study was to optimise a collagenase perfusion protocol for the isolation of a liver non-parenchymal cell (NPC) suspension enriched for Kupffer cells that reduced damage to F4/80 antigen cell surface expression to allow analysis by flow cytometry. Kupffer cell-enriched liver NPCs were isolated from C57BL/6 mice using different protocols. Flow cytometry was used to examine the effect of collagenase digestion on F4/80 expression on Kupffer cells, and results were represented by the percentage of F4/80 positive cells and by the F4/80 mean fluorescence intensity (MFI). The perfusion temperature, concentration of collagenase solution and total dosage of collagenase for liver perfusion influenced the effect of collagenase perfusion on the expression of F4/80 antigen on Kupffer cells. Collagenase perfusion at 28°C resulted in an increased percentage of F4/80 positive cells ( P = 0.001) and MFI ( P = 0.005) compared with 37°C. Perfusion with a total dose of 1.0 g/kg BW collagenase (using a 0.75 mg/mL solution) resulted in the highest percentage of F4/80 positive cells ( P = 0.001) compared with 0.8 g/kg BW and 1.2 g/kg BW collagenase. Isolation of cells using the modified protocol resulted in a higher percentage of Kupffer cells ( P < 0.001) and a higher MFI of F4/80 antigen ( P < 0.001) compared with the common protocol. [ABSTRACT FROM AUTHOR]

Purpose: P-selectin receptor is expressed in platelets and endothelial cells in a cell-activation-dependent manner. Platelet P-selectin (CD62) levels may become elevated in a number of vasoocclusive diseases, including arteriosclerosis, atherothrombosis, and diabetes mellitus (DM). Nonarteritic anterior ischemic optic neuropathy (NAION) is associated with a sudden loss of vision due to the vascular insufficiency of ciliary arteries supplying the optic nerve. In this study, our aim was to investigate the presence of increased platelet reactivity in the development of NAION. Methods: Twenty-one NAION patients, 39 healthy control subjects, and 44 patients suffering from diabetes mellitus (DM) were examined in our case-control, pilot study. Platelet activation was investigated by flow cytometric analysis of the mean fluorescence intensity (MFI) of CD62 on platelets. These results were compared among the different study groups. Results: NAION patients showed considerably although not signifactly ( p = 0.2017) higher P-selectin MFI values (71.98 ± 40.30) versus healthy subjects (55.48 ± 20.95), insulin-dependent DM patients (50.02 ± 13.08), and non-insulin-dependent DM subjects (54.72 ± 24.74). However, logistic regression analysis resulted in a statistically significant adjusted effect on the odds of NAION when CD62 MFI values were logarithmically transformed (OR: 3.86, 95 % CI: 1.10 to 13.53, p = 0.0346). Conclusion: Elevated platelet CD62 positivity may be related to NAION, suggesting a possible role of enlarged platelet activity in the generation of this type of ischemic optic neuropathy. [ABSTRACT FROM AUTHOR]

Abstract: Phosphorodiamidate morpholino oligomers (PMO) are synthetic antisense molecules that interfere with translation, pre-mRNA splicing and RNA synthesis. Like other gene-silencing technologies, PMO are poorly taken up by primary leukocytes without the use of physical or chemical delivery techniques. We sought an alternative delivery mechanism of PMO into immune cells that eliminates the need for such manipulations. Here we demonstrate the first use of arginine-rich cell-penetrating peptides (CPPs) to deliver PMO (P-PMO) directly into primary murine leukocytes for inhibition of gene expression and promotion of altered pre-mRNA splicing. We compared the P-PMO delivery efficacy of four arginine-rich CPPs including HIV Tat and penetratin, and one histidine rich CPP, and found that the (RXR)4 peptide was the most efficacious for PMO delivery and targeted antisense effect. The delivery and antisense effects of P-PMO are time- and dose-dependent and influenced by the activation and maturation states of T cells and dendritic cells, respectively. Targeted expression of several genes using P-PMO is shown including surface signaling proteins (CD45 and OX-40), a cytokine (interleukin-2), and a nuclear transcription factor (Foxp3). Considering the abundance of naturally occurring alternatively spliced gene products involved in immune regulation, P-PMO offer an effective method for modulating gene activity for immunological research and applications beyond traditional antisense approaches. [Copyright &y& Elsevier]

Abstract: The optimisation of a flow cytometric protocol for the determination of the estrogen receptor β (ERβ) expression in bovine blood neutrophils is described. The following final incubation conditions were obtained: fixation with 0.25% formaldehyde and 70% methanol, both for 1 h; permeabilisation with 0.05% Triton X-100, overnight labelling at 4 °C with the primary antibody diluted at 10 μg/ml and subsequent labelling for 30 min on ice with the fluorescein isothiocyanate-conjugated secondary antibody at 8 μg/ml. Of the three anti-human or anti-rat ERβ primary antibodies evaluated, only PA1-311 was found to cross-react with bovine cells. Immunoblot analysis supports the obtained results. The flow cytometric technique allows reproducible quantitative determination of the ERβ protein in neutrophils and may be a valuable tool for future expression studies in these cells of the innate immune system. [Copyright &y& Elsevier]

Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired disorder of the pluripotent stem cell resulting from the somatic mutation of the X-linked PIG-A gene, involved in the synthesis of the glycosylphosphatidyl-inositol anchor of membrane proteins such as CD55, CD59 and CD14. In the past decade, flow cytometry has become a valuable diagnostic tool in the detection of deficient expression of the GPI-anchored proteins. We report the diagnosis of PNH in four patients confirmed by flow cytometry. Red blood cells, granulocytes and monocytes were classified as PNH types I, II and III according to the mean fluorescence intensities (MFI) of membrane proteins. MFI rate is a numerical data reflecting the severity of decreased antigen expression, and it is obtained by dividing the MFI of the type II or type III cells by the MFI of the respective cells obtained for a normal sample. We found that the investigation of granulocytes and monocytes was more informative than red blood cells when percent negativity was evaluated. In addition, the lowest MFI rate (mean 0.011) was obtained for CD14 on monocytes while CD59 and CD55 gave higher values on all three investigated cell types (0.021–0.34). Thus, CD14 on monocytes seems to be the most reliable marker for establishing the PNH clone size and the severity of antigen deficiency. [ABSTRACT FROM AUTHOR]

: ObjectivesTo address the potential role of the endothelial lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) in the thrombotic system, in this study we first examined whether platelet interaction with LOX-1 generated reactive oxygen species (ROS) and superoxide (O2·−) and then investigated the relationship between the intracellular production of O2·− and the availability of nitric oxide (NO).: BackgroundOxidative inactivation of NO is regarded as an important cause of its decreased biologic activity which may favor platelet-dependent arterial thrombosis.: MethodsBovine aortic endothelial cells (BAECs) and Chinese hamster ovary-K1 cells stably expressing bovine LOX-1 (BLOX-1-CHO) were incubated at different times with human platelets. The ROS, O2·−, and NO were measured in cells by flow cytometry.: ResultsThe incubation of BAECs and BLOX-1-CHO cells with human platelets induced a sharp and dose-dependent increase in intracellular concentration of ROS and O2·− (p from <0.01 to <0.001). The increase in intracellular concentration of O2·− was followed by a dose-dependent reduction in basal and bradykinin-induced intracellular NO concentration (p from <0.01 to <0.001). The increase in O2·− and the reduction of NO were inhibited by the presence of vitamin C and anti-LOX-1 monoclonal antibody (p < 0.001).: ConclusionsThe results of this study show that one of the pathophysiologic consequences of platelet binding to LOX-1 may be the inactivation of NO through an increased cellular production of O2·−. [Copyright &y& Elsevier]

Despite growing interest about the impact of donor‐specific HLA antibodies (DSA) in LT limited data are available for pediatric recipients. Our aim was to perform a retrospective single‐center chart review of children (0‐16 years) having undergone LT between January 1, 2005 and December 31, 2017, to characterize DSA, to identify factors associated with the development of de novo DSA, and to analyze potential associations with the diagnosis of TCMR. Information on patient‐ and donor‐characteristics and LB reports were analyzed retrospectively. Serum obtained before LT and at LB was analyzed for presence of recipient HLA antibody using Luminex® technology. MFI > 1000 was considered positive. In 63 pediatric LT recipients with a median follow‐up of 72 months, the overall prevalence of de novo DSA was 60.3%. Most were directed against class II antigens (33/38, 86.8%). Preformed DSA were present in 30% of patients. Twenty‐eight (28/63) patients (44.4%) presented at least one episode of TCMR, mostly (12/28, 43%) moderate (Banff 6‐7). De novo DSA were significantly more frequent in patients with TCMR than in patients without (75% vs 48.6%, P =.03), and patients with preformed and de novo DSA had a significantly higher rate of TCMR than patients without any DSA (66.7% vs 20%, P =.02). Neither preformed DSA nor de novo DSA were associated with frequency or severity of TCMR. Recipients with lower weight at LT developed de novo DSA more frequently (P =.04). De novo DSA were highly prevalent in pediatric LT recipients. Although associated with the development of TCMR, they did not appear to impact the frequency or severity of TCMR or graft survival. Instead, de novo DSA may suggest a state of insufficient IS. [ABSTRACT FROM AUTHOR]

Aim: Primary immunodeficiency diseases are serious public health problems in Turkey. Accurate and early diagnosis is critical for these patients for appropriate therapeutic options. In this study, optimization and standardization of intracellular DOCK8, LRBA, SAP and XIAP protein expressions in heathy controls with a single flow cytometer protocol were provided. In addition, the protocol was also used in the diagnosis of clinically relevant patients. Methods: Heparinized blood samples from patients and healthy controls were drawn. Peripheral blood mononuclear cells (PBMC) were immediately isolated. Then, DOCK8, LRBA, SAP and XIAP protein expressions were determined in PBMCs by flow cytometer. The data were analyzed as mean fluorescein intensity difference (ΔMFI) according to the isotype. Results: ΔMFI values obtained by DOCK8 antibody staining were determined as 21.3±4 in CD3+T cells and 25±3.3 in CD20+T cells in healthy controls. Patients with DOCK8 deficiency showed values either very low or completely absent. ΔMFI values obtained by LRBA antibody staining were observed as 36±7.7 in healthy controls, while those values in the LRBA deficiency patients were identified at very low levels of 5.9±1.8. These values obtained by SAP and XIAP antibody staining were determined as 30.2±3 in CD8+T cells for SAP, 13.9±3.2 in CD3+T and 14.6±3.5 in CD20+B cells for XIAP. Conclusion: Due to its rapid and reliable results in clinically relevant cases for DOCK8, LRBA, SAP and XIAP, analysis of intracellular protein expression by flow cytometry can be used as a diagnostic procedure. Patients with remarkably decreased protein expressions or ΔMFI values compared to simultaneous healthy controls and isotype controls should be confirmed with gene sequencing. [ABSTRACT FROM AUTHOR]