Effect of serum panel reactive antibodies on allogeneic hematopoietic stem cell transplantation in pediatric thalassemia patients: A single-center experience.

BACKGROUND: The aim of this study was to assess the impact of serum panel reactive antibodies (PRA) on the outcomes of allogeneic hematopoietic stem cell transplantation (HSCT) in pediatric thalassemia patients. METHODS: A total of 73 pediatric patients with thalassemia were included in this single-center study. Pre-transplant PRA levels were evaluated, and the patients were divided into two groups: PRA-negative (group 1; n = 44) and PRA-positive (group 2; n = 29). Patient characteristics, including age, gender, donor type, stem cell source, and HLA compatibility, were analyzed. Transplant outcomes, including engraftment, transfusion requirements, and transplant-related complications, were compared between the two groups. Further subgroup analysis was performed based on MFI values. RESULTS: At the time of transplantation, patients in group 1 were younger than those in group 2 (p = .008). The number of fully matched donors within the family (MSD and MFD) was significantly higher in group 1 (p = .049). Additionally, Rh blood group incompatibility was higher in group 2 (p = .03). There was no statistically significant difference in the engraftment days of neutrophils, platelets, and erythrocytes between the two groups. The frequency of poor graft function and graft failure was higher in the group 2, but there was no statistically significant difference. Post-transplant transfusion requirements for platelets and red blood cells were significantly higher in the group 2 (p < .001). Transplant-related complications such as VOD, PRES, and aGvHD were more common in the group 2, but no statistical significance was detected. CONCLUSIONS: Serum PRA in pediatric thalassemia patients may impact the outcomes of HSCT. PRA-positive patients had higher rates of blood product transfusion requirements. Although poor graft function, graft failure, and post-transplant complications were more common in the group 2, statistical significance was not observed. Identifying patients with high PRA levels can assist in optimizing transplant strategies and post-transplant care, leading to improved outcomes for the patients.

Comparison of Bretschneider HTK and Blood Cardioplegia (4:1): A Prospective Randomized Study.

BACKGROUND: We compared the effect of intermittent blood and histidine-tryptophan-ketoglutarate (HTK) solution of Bretschneider on myocardial histopathology and perioperative outcome. METHODS: Forty adult cardiac surgery patients were grouped into two (n = 20 for each): (1) Intermittent blood cardioplegia (IBC): had repeated cold 4:1 blood cardioplegia and (2) HTK: had a single dose of cold HTK for cardioprotection. Creatine kinase (CK)-MB, Troponin-I (cTn-I), pH, and lactate were studied in coronary sinus blood before and after aortic cross-clamping (AXC) and systemic blood at postoperative 6th, 24th, and 48th hours. Myocardial biopsy was performed before and after AXC for light microscopy. Vacuolation, inflammation, edema, and glycogen were graded semiquantitatively (from 0 to 3). The myocardial apoptotic index was evaluated via the terminal deoxynucleotidyl transferase dUTP nick end labeling. RESULTS: There were no differences in perioperative clinical outcomes between the groups. The coronary sinus samples after AXC were more acidotic (7.15 ± 0.14 vs. 7.32 ± 0.07, p = 0.001) and revealed higher CK-MB (21.0 ± 12.81 vs. 12.60 ± 11.80, p = 0.008) in HTK compared with IBC. The HTK had significantly a higher amount of erythrocyte suspension intraoperatively compared with IBC (0.21 ± 0.53 vs. 1.68 ± 0.93 U, p = 0.001). Microscopically, myocardial edema was more pronounced in HTK compared with IBC after AXC (2.25 ± 0.91 vs. 1.50 ± 0.04, p = 0.013). While a significant increase in the apoptotic index was seen after AXC in both groups (p = 0.001), no difference was detected between the groups (p = 0.417). CONCLUSION: IBC and HTK have a similar clinical outcome and protective effect, except for more pronounced myocardial edema and increased need for intraoperative transfusion with HTK.

Autologous bone marrow-derived nucleated cell (aBMNC) transplantation improves endometrial function in patients with refractory Asherman's syndrome or with thin and dysfunctional endometrium.

PURPOSE: The purpose was to evaluate the effect of intrauterine injection of aBMNC on the endometrial function in patients with refractory Asherman's syndrome (AS) and/or thin and dysfunctional endometrium (TE). STUDY DESIGN: This is a prospective, experimental, non-controlled study MATERIAL AND METHODS: The study was carried out between December 2018 and December 2020 on 20 patients, who were of age < 45 years and had oligo/amenorrhea and primary infertility due to refractory AS and/or TE. One hundred ml BM was extracted. aBMNC cells were separated according to generic volume reduction protocol by using the Cell Separation System SEPAX S-100 table top centrifuge system. We have evaluated CD34+, mononuclear cell (MNC), and total nucleated cell (TNC) counts. The transplantation aBMNC was performed by two intrauterine injections at an interval of one week, transvaginally into the endometrial-myometrial junction by an ovum aspiration needle. Midcyclic endometrial thickness (ET) and gestations after transplantation were evaluated. RESULTS: The mean TNC, MNC, and CD34+ cells were 11.55 ± 4.7 × 108, 3.85 ± 2.01 × 108, and 7.00 ± 2.88 × 106 at first injection, respectively, and 6.85 ± 2.67 × 108, 2.04 ± 1.11 × 108, and 3.44 ± 1.31 × 106 at second injection, respectively. The maximum posttransplantation ET was significantly higher than the maximum pretransplantation ET: 2.97 ± 0.48 vs. 5.76 ± 1.19 (mean ± standard deviation, p < 0.01). Twelve patients had frozen-thaw embryo transfers after the study. In 42% (n = 5 of 12) of the patients, pregnancy was achieved. One of the five patients delivered a healthy baby at term. CONCLUSIONS: Autologous BMNC transplantation may contribute to endometrial function in patients with AS and/or TE.

Regulation and function of the cytosolic viral RNA sensor RIG-I in pancreatic beta cells.

Enteroviral infections are associated with type I diabetes. The mechanisms by which viruses or viral products such as double-stranded RNA (dsRNA) affect pancreatic beta cell function and survival remain unclear. We have shown that extracellular dsRNA induces beta cell death via Toll-like receptor-3 (TLR3) signaling whereas cytosolic dsRNA triggers the production of type I interferons and apoptosis via a TLR3-independent process. We presently examined expression of the intracellular viral RNA sensors, the RNA helicases RIG-I and MDA5, and documented the functionality of RIG-I in pancreatic beta cells. FACS-purified rat beta cells and islet cells from wild-type or TLR3(-/-) mice were cultured with or without the RIG-I-specific ligand 5'-triphosphate single-stranded RNA (5'triP-ssRNA), the synthetic dsRNA polyI:C (PIC) or 5'OH-ssRNA (negative control); the RNA compounds were added in the medium or transfected in the cells using lipofectamine. RIG-I and MDA5 expression were determined by real-time RT-PCR. NF-kappaB and IFN-beta promoter activation were studied in the presence or absence of a dominant-negative form of RIG-I (DN-RIG-I). Both extracellular (PICex) and intracellular (PICin) PIC increased expression of RIG-I and MDA5 in pancreatic beta cells. TLR3 deletion abolished PICex-induced up-regulation of the helicases in beta cells but not in dendritic cells. PICin-induced NF-kappaB and IFN-beta promoter activation were prevented by the DN-RIG-I. The RIG-I-specific ligand 5'triP-ssRNA induced IFN-beta promoter activation and beta cell apoptosis. Our results suggest that the RIG-I pathway is present and active in beta cells and could contribute to the induction of insulitis by viral RNA intermediates.

Free fatty acids and cytokines induce pancreatic beta-cell apoptosis by different mechanisms: role of nuclear factor-kappaB and endoplasmic reticulum stress.

Apoptosis is probably the main form of beta-cell death in both type 1 diabetes mellitus (T1DM) and T2DM. In T1DM, cytokines contribute to beta-cell destruction through nuclear factor-kappaB (NF-kappaB) activation. Previous studies suggested that in T2DM high glucose and free fatty acids (FFAs) are beta-cell toxic also via NF-kappaB activation. The aims of this study were to clarify whether common mechanisms are involved in FFA- and cytokine-induced beta-cell apoptosis and determine whether TNFalpha, an adipocyte-derived cytokine, potentiates FFA toxicity through enhanced NF-kappaB activation. Apoptosis was induced in insulinoma (INS)-1E cells, rat islets, and fluorescence-activated cell sorting-purified beta-cells by oleate, palmitate, and/or cytokines (IL-1beta, interferon-gamma, TNFalpha). Palmitate and IL-1beta induced a similar percentage of apoptosis in INS-1E cells, whereas oleate was less toxic. TNFalpha did not potentiate FFA toxicity in primary beta-cells. The NF-kappaB-dependent genes inducible nitric oxide synthase and monocyte chemoattractant protein-1 were induced by IL-1beta but not by FFAs. Cytokines activated NF-kappaB in INS-1E and beta-cells, but FFAs did not. Moreover, FFAs did not enhance NF-kappaB activation by TNFalpha. Palmitate and oleate induced C/EBP homologous protein, activating transcription factor-4, and immunoglobulin heavy chain binding protein mRNAs, X-box binding protein-1 alternative splicing, and activation of the activating transcription factor-6 promoter in INS-1E cells, suggesting that FFAs trigger an endoplasmic reticulum (ER) stress response. We conclude that apoptosis is the main mode of FFA- and cytokine-induced beta-cell death but the mechanisms involved are different. Whereas cytokines induce NF-kappaB activation and ER stress (secondary to nitric oxide formation), FFAs activate an ER stress response via an NF-kappaB- and nitric oxide-independent mechanism. Our results argue against a unifying hypothesis for the mechanisms of beta-cell death in T1DM and T2DM.

Double-stranded RNA induces pancreatic beta-cell apoptosis by activation of the toll-like receptor 3 and interferon regulatory factor 3 pathways.

OBJECTIVE: Viral infections contribute to the pathogenesis of type 1 diabetes. Viruses, or viral products such as double-stranded RNA (dsRNA), affect pancreatic beta-cell survival and trigger autoimmunity by unknown mechanisms. We presently investigated the mediators and downstream effectors of dsRNA-induced beta-cell death. RESEARCH DESIGN AND METHODS: Primary rat beta-cells and islet cells from wild-type, toll-like receptor (TLR) 3, type I interferon receptor (IFNAR1), or interferon regulatory factor (IRF)-3 knockout mice were exposed to external dsRNA (external polyinosinic-polycytidylic acid [PICex]) or were transfected with dsRNA ([PICin]). RESULTS: TLR3 signaling mediated PICex-induced nuclear factor-kappaB (NF-kappaB) and IRF-3 activation and beta-cell apoptosis. PICin activated NF-kappaB and IRF-3 in a TLR3-independent manner, induced eukaryotic initiation factor 2 alpha phosphorylation, and triggered a massive production of interferon (IFN)-beta. This contributed to beta-cell death, as islet cells from IFNAR1(-/-) or IRF-3(-/-) mice were protected against PICin-induced apoptosis. CONCLUSIONS: PICex and PICin trigger beta-cell apoptosis via the TLR3 pathway or IRF-3 signaling, respectively. Execution of PICin-mediated apoptosis depends on autocrine effects of type I IFNs.

Selective inhibition of eukaryotic translation initiation factor 2 alpha dephosphorylation potentiates fatty acid-induced endoplasmic reticulum stress and causes pancreatic beta-cell dysfunction and apoptosis.

Free fatty acids cause pancreatic beta-cell apoptosis and may contribute to beta-cell loss in type 2 diabetes via the induction of endoplasmic reticulum stress. Reductions in eukaryotic translation initiation factor (eIF) 2alpha phosphorylation trigger beta-cell failure and diabetes. Salubrinal selectively inhibits eIF2alpha dephosphorylation, protects other cells against endoplasmic reticulum stress-mediated apoptosis, and has been proposed as a beta-cell protector. Unexpectedly, salubrinal induced apoptosis in primary beta-cells, and it potentiated the deleterious effects of oleate and palmitate. Salubrinal induced a marked eIF2alpha phosphorylation and potentiated the inhibitory effects of free fatty acids on protein synthesis and insulin release. The synergistic activation of the PERK-eIF2alpha branch of the endoplasmic reticulum stress response, but not of the IRE1 and activating transcription factor-6 pathways, led to a marked induction of activating transcription factor-4 and the pro-apoptotic transcription factor CHOP. Our findings demonstrate that excessive eIF2alpha phosphorylation is poorly tolerated by beta-cells and exacerbates free fatty acid-induced apoptosis. This modifies the present paradigm regarding the beneficial role of eIF2alpha phosphorylation in beta-cells and must be taken into consideration when designing therapies to protect beta-cells in type 2 diabetes.

Toll-like receptor 3 and STAT-1 contribute to double-stranded RNA+ interferon-gamma-induced apoptosis in primary pancreatic beta-cells.

Viral infections and local production of cytokines probably contribute to the pathogenesis of Type 1 diabetes. The viral replicative intermediate double-stranded RNA (dsRNA, tested in the form of polyinosinic-polycytidylic acid, PIC), in combination with the cytokine interferon-gamma (IFN-gamma), triggers beta-cell apoptosis. We have previously observed by microarray analysis that PIC induces expression of several mRNAs encoding for genes downstream of Toll-like receptor 3 (TLR3) signaling pathway. In this report, we show that exposure of beta-cells to dsRNA in combination with IFN-alpha, -beta, or -gamma significantly increases apoptosis. Moreover, dsRNA induces TLR3 mRNA expression and activates NF-kappaB and the IFN-beta promoter in a TRIF-dependent manner. dsRNA also induces an early (1 h) and sustained increase in IFN-beta mRNA expression, and blocking IFN-beta with a specific antibody partially prevents PIC plus IFN-gamma-induced beta-cell death. On the other hand, dsRNA plus IFN-gamma does not induce apoptosis in INS-1E cells, and expression of TLR3 and type I IFNs mRNAs is not detected in these cells. Of note, disruption of the STAT-1 signaling pathway protects beta-cells against dsRNA plus IFN-gamma-induced beta-cell apoptosis. This study suggests that dsRNA plus IFN-gamma triggers beta-cell apoptosis by two complementary pathways, namely TLR3-TRIF-NF-kappaB and STAT-1.

Macrophages and stromal cells phagocytose apoptotic bone marrow-derived B lineage cells.

It has been hypothesized that B cell precursors that undergo programmed cell death due to nonproductive Ig gene rearrangements are cleared from the bone marrow by macrophages. However, a role for macrophages in this process is supported only by micrographs showing their association with apoptotic-appearing, B lineage cells. Functional data demonstrating phagocytosis of apoptotic, bone marrow lymphocytes by macrophages have not been presented, nor have receptors potentially involved in that process been identified. The data in this report demonstrate that macrophages isolated from murine bone marrow efficiently phagocytose apoptotic murine B lineage cells using multiple receptors that include CD14, integrins, class A scavenger receptor, and CD31 (PECAM-1). In addition, the results further reveal a new role for the hemopoietic microenvironment in B cell development in view of data demonstrating that murine bone marrow stromal cells are also capable of clearing apoptotic cells via an integrin-dependent mechanism.

Effects of prolactin on cloned human T-lymphocytes.

To evaluate the possible role of prolactin (PRL) in T-lymphocytes, we monitored gene induction in one cytotoxic T-lymphocyte (CTL) clone derived from a patient with hemochromatosis and in several T-helper clones generated from a normal donor and a patient with multiple sclerosis. The CTL clone expressed conventional PRL receptor (PRLR), and PRL induced the expression of suppressor of cytokine signaling-3 (SOCS-3) and increased the expression of SOCS-2 and cytokine-inducible src homology-2 containing protein (CIS, another member of the SOCS family). As is the case in granulocytes, expression of a conventional receptor for PRL could not be shown by polymerase chain reaction analysis on three helper clones. In addition, as in granulocytes, PRL modulated the expression of genes such as the interferon-regulatory factor-1, inducible nitric oxide synthase, CIS, and SOCS-2. These effects were also elicited with ovine PRL and could be prevented by anti-PRL antibodies. Thus, the use of clones allowed the detection of direct effects of PRL on T-cells, even when these have few or no detectable PRLR, confirming that human T-lymphocytes are targets for PRL.