ABO-incompatible kidney transplantation can be successfully conducted by monitoring IgM isoagglutinin titers during desensitization.

BACKGROUND: Recent advances in desensitization techniques and immunosuppressive therapy have led to improved outcomes after ABO-incompatible (ABO-i) kidney transplantation (KT). However, questions remain unanswered, particularly regarding which type of ABO isoagglutinin-immunoglobulin M (IgM) or immunoglobulin M (IgG)-is significantly involved in antibody-mediated rejection (AMR). STUDY DESIGN AND METHODS: We retrospectively analyzed data from 120 patients who underwent ABO-i KT between 2012 and 2014. Preoperative plasma exchange was performed until the IgM isoagglutinin titer was 4 or less, regardless of the IgG titer. Clinical data were compared between patient groups with pre-KT IgG isoagglutinin titer 16 or greater (high IgG; titer range, 16-256; n = 39) and 8 or less (low IgG; titer range, -8; n = 81). RESULTS: The median follow-up periods were 59 (high IgG) and 55 (low IgG) months. Patient survival at 5 years (p = 0.314) was 100% (high IgG) and 97.4% (low IgG). Graft survival at 5 years (p = 0.480) was 100% (high IgG) and 98.7% (low IgG). AMR by anti-ABO antibody occurred in only one patient in the low-IgG group. CONCLUSION: Patients with high pre-KT IgG isoagglutinin titers had equally successful outcomes as those with low IgG titers. ABO-i KT can be successfully performed by reducing the pre-KT IgM isoagglutinin titer to 4 or less, as determined by the immediate spin tube method.

Reconstitution of T and NK cells after haploidentical hematopoietic cell transplantation using αß T cell-depleted grafts and the clinical implication of γδ T cells.

To investigate reconstitution of T and NK cells after αß T lymphocyte-depleted haploidentical hematopoietic cell transplantation (HHCT) and the clinical implications of γδ T cells, we analyzed 50 pediatric patients who received 55 HHCTs using αß T cell-depleted grafts. The number of CD3+ T cells and CD8+ T cells recovered rapidly and reached donor levels at days 180 and 60, respectively. Recovery of NK cells was rapid, and the median of NK cells at day 14 was comparable to the donor level. At day 14, median percentage of γδ T lymphocytes was 70.5%. After day 14, the percentage of γδ T cells gradually decreased, while the percentage of αß T cells gradually increased. Patients with a low percentage (≤21%) of γδ T cells at day 30 had significantly higher incidence of cytomegalovirus (CMV) reactivation compared to patients with a high percentage (>70%) of γδ T cells (P < .01). In patients with acute leukemia, patients with high percentage of γδ T cells at day 30 showed significantly higher relapse-free survival compared to those with low percentage of γδ T cells (P = .02). Data suggest that early recovery of γδ T cells decreases the risk of CMV reactivation and leukemia relapse.

Effects of therapeutic plasma exchange on early allograft dysfunction after liver transplantation.

BACKGROUND: Early allograft dysfunction (EAD) is a serious complication of liver transplantation (LT) and is associated with graft failure, which can result in patient mortality. Due to the shortage of organs for retransplantation, only a small proportion of EAD patients undergo retransplantation. Thus, liver support is needed for most patients with EAD. METHODS: We evaluated the effects of therapeutic plasma exchange (TPE) in EAD patients. EAD was defined as a sustained hyperbilirubinemia (≥10 mg/dL) within 30 days of LT without concurrent biliary complications. In a 13-year period, 107 EAD patients underwent TPE while 36 EAD patients did not. We investigated the laboratory and clinical outcomes of TPE and non-TPE groups. RESULTS: The TPE group showed 1-month and 1-year survival rates of 82.2% and 53.8%, respectively, whereas the non-TPE group showed 58.3% and 22.2%, respectively. In TPE group, statistically significant decreases (P < 0.05) in total bilirubin (15.2 ± 5.2 to 13.1 ± 5.4 mg/dL), and INR (1.72 ± 1.04 to 1.38 ± 1.14), were seen after the final TPE session. TPE responder groups with age <51 years, total bilirubin <11.1 mg/dL, or INR <1.15 after final TPE showed better prognosis. TPE decreased the hazard risk of death in EAD patients whereas older age, male gender, and higher INR on the day of EAD onset increased the risk. CONCLUSIONS: TPE effectively removed plasma bilirubin and improved coagulation function in EAD patients, with higher survival in the TPE group than in the non-TPE group. TPE may be an effective liver support for EAD patients. J. Clin. Apheresis 32:147-153, 2017. © 2016 Wiley Periodicals, Inc.

Natural killer cells regulate eosinophilic inflammation in chronic rhinosinusitis.

Eosinophils play a major pathologic role in the pathogenesis of diverse inflammatory diseases including chronic rhinosinusitis (CRS). Dysregulated production of prostaglandin (PG), particularly PGD2, is considered to be an important contributing factor to eosinophilic inflammation in CRS primarily through proinflammatory and chemotactic effects on eosinophils. Here, we provide evidence that PGD2 can promote eosinophilic inflammation through a suppression of Natural killer (NK) cell effector function and NK cell-mediated eosinophil regulation. Eosinophil apoptosis mediated by NK cells was significantly decreased in CRS patients compared with healthy controls. This decrease was associated with NK cell dysfunction and eosinophilic inflammation. Tissue eosinophils were positively correlated with blood eosinophils in CRS patients. In a murine model of CRS, NK cell depletion caused an exacerbation of blood eosinophilia and eosinophilic inflammation in the sinonasal tissue. PGD2 and its metabolite, but not PGE2 and a panel of cytokines including TGF-ß, were increased in CRS patients compared with controls. Effector functions of NK cells were potently suppressed by PGD2-dependent, rather than PGE2-dependent, pathway in controls and CRS patients. Thus, our results suggest decreased NK cell-mediated eosinophil regulation, possibly through an increased level of PGD2, as a previously unrecognized link between PG dysregulation and eosinophilic inflammation in CRS.

Red Blood Cell Transfusion in Patients With Autoantibodies: Is It Effective and Safe Without Increasing Hemolysis Risk?

BACKGROUND: The therapeutic efficacy of red blood cell (RBC) transfusions in patients with autoimmune hemolytic anemia (AIHA) is highly debated because of speculations on the increased risk of transfusion reactions; yet it is a suggested adjuvant therapy in anemic patients with life-threatening hypoxemia. In this study, we evaluated the safety and efficacy of RBC transfusions in AIHA patients. METHODS: Daily changes in hemoglobin, total bilirubin, and lactate dehydrogenase (LDH) were assessed in 161 AIHA patients without bleeding history who were transfused once with 1-5 units of the least-incompatible RBCs and monitored over a seven-day period. Post-transfusion patients positive for alloantibodies only or those without RBC-specific antibodies were considered as control groups (N=100 for both groups). RESULTS: The three groups revealed similar increases in hemoglobin of 1.40-1.70 g/dL (autoantibodies), 1.20-1.60 g/dL (alloantibodies only), and 1.40-1.55 g/dL (no antibodies) for seven days following transfusion of 10 mL RBCs/kg. During follow-up, no significant changes in total bilirubin or LDH levels were detected in the AIHA group compared with controls. Influences due to autoantibody type, direct antiglobulin test (DAT) specificity and strength, and steroid therapy status on transfusion reactions were not evident in AIHA patients. In addition, changes in hemoglobin levels were significantly higher (P<0.001) in severe anemia (<5 g/dL) than in other patients. CONCLUSIONS: Transfusion of the least-incompatible RBCs in AIHA patients is effective and safe without any associated increase in hemolysis risk when compared with post-transfusion patients positive for alloantibodies or those lacking RBC-specific antibodies.

NK cell function triggered by multiple activating receptors is negatively regulated by glycogen synthase kinase-3ß.

Activation of NK cells is triggered by combined signals from multiple activating receptors that belong to different families. Several NK cell activating receptors have been identified, but their role in the regulation of effector functions is primarily understood in the context of their individual engagement. Therefore, little is known about the signaling pathways broadly implicated by the multiple NK cell activation cues. Here we provide evidence pointing to glycogen synthase kinase (GSK)-3ß as a negative regulator of multiple NK cell activating signals. Using an activation model that combines NKG2D and 2B4 and tests different signaling molecules, we found that GSK-3 undergoes inhibitory phosphorylation at regulatory serine residues by the engagement of NKG2D and 2B4, either individually or in combination. The extent of such phosphorylation was closely correlated with the degree of NK cell activation. NK cell functions, such as cytokine production and cytotoxicity, were consistently enhanced by the knockdown of GSK-3ß or its inhibition with different pharmacological inhibitors, whereas inhibition of the GSK-3α isoform had no effect. In addition, NK cell function was augmented by the overexpression of a catalytically inactive form of GSK-3ß. Importantly, the regulation of NK cell function by GSK-3ß was common to diverse activating receptors that signal through both ITAM and non-ITAM pathways. Thus, our results suggest that GSK-3ß negatively regulates NK cell activation and that modulation of GSK-3ß function could be used to enhance NK cell activation.

Therapeutic DC vaccination with IL-2 as a consolidation therapy for ovarian cancer patients: a phase I/II trial.

While ovarian cancer (OvCa) responds well to surgery and conventional chemotherapy, a high recurrence rate of advanced OvCa is observed. In this phase I/II study, 10 OvCa patients with minimal residual disease were treated with autologous dendritic cells (DCs) and IL-2 to evaluate the safety and feasibility of this therapeutic strategy and to characterize the antigen-specific immune alterations induced through this treatment. Approximately 4 months after initial debulking and chemotherapy, patients received two subcutaneous doses of autologous monocyte-derived DCs pulsed with autologous tumor lysate and keyhole limpet hemocyanin (KLH) at 4-week intervals. After each DC inoculation, low-dose (200 mIU) IL-2 was introduced for 14 consecutive days as an immune adjuvant. The vaccination was well tolerated. In three out of 10 patients, the inclusion status after the initial therapy showed the maintenance of complete remission (CR) after DC vaccination for 83, 80.9 and 38.2 months without disease relapse. One patient with stable disease (SD) experienced the complete disappearance of tumor after DC vaccination, and this status was maintained for 50.8 months until tumor recurrence. In two patients with partial response (PR) was not responding to DC vaccination and their disease recurred. In the three patients with disease free long-term survival, significant immune alterations were observed, including increased natural killer (NK) activity, IFN-γ-secreting T cells, immune-stimulatory cytokine secretion and reduced immune-suppressive factor secretion after DC vaccination. Thus, in patients with NED status and increased overall survival, DC vaccination induced tumor-related immunity, potentially associated with long-term clinical responses against OvCa.

Attenuation of natural killer cell functions by capsaicin through a direct and TRPV1-independent mechanism.

The assessment of the biological activity of capsaicin, the compound responsible for the spicy flavor of chili pepper, produced controversial results, showing either carcinogenicity or cancer prevention. The innate immune system plays a pivotal role in cancer pathology and prevention; yet, the effect of capsaicin on natural killer (NK) cells, which function in cancer surveillance, is unclear. This study found that capsaicin inhibited NK cell-mediated cytotoxicity and cytokine production (interferon-γ and tumor necrosis factor-α). Capsaicin impaired the cytotoxicity of NK cells, thereby inhibiting lysis of standard target cells and gastric cancer cells by modulating calcium mobilization in NK cells. Capsaicin also induced apoptosis in gastric cancer cells, but that effect required higher concentrations and longer exposure times than those required to trigger NK cell dysfunction. Furthermore, capsaicin inhibited the cytotoxicity of isolated NK cells and of an NK cell line, suggesting a direct effect on NK cells. Antagonists of transient receptor potential vanilloid subfamily member 1 (TRPV1), a cognate capsaicin receptor, or deficiency in TRPV1 expression failed to prevent the defects induced by capsaicin in NK cells expressing functional TRPV1. Thus, the mechanism of action of capsaicin on NK cells is largely independent of TRPV1. Taken together, capsaicin may have chemotherapeutic potential but may impair NK cell function, which plays a central role in tumor surveillance.

Significance of isoagglutinin titer in ABO-incompatible kidney transplantation.

ABO-incompatible (ABO-i) kidney transplantation (KT) has emerged for overcoming the shortage of organ donors. Although this technique initially achieved only low graft survival due to isoagglutinin, recently developed desensitization protocols have improved survival to levels that are comparable to ABO-compatible KT. However, isoagglutinin is still regarded as a major obstacle to ABO-i KT. In this study, we evaluate the impact of isoagglutinin titer on clinical outcomes as well as factors that may influence isoagglutinin titers. In total, data from 95 patients who underwent ABO-i KT were analyzed. Preoperatively, rituximab administration and plasmapheresis were performed until the titer was reduced to ≤1:4. Retrospective analysis included blood group; timing and dosage of rituximab; isoagglutinin titer; number of plasmapheresis; and clinical outcomes including graft survival and serum creatinine. Graft survival was 95.8% (n = 91) and average serum creatinine at 1- and 1.5-year post-ABOi-KT was 1.3. Three patients died of sepsis. The identified predictors of titer-rebound after transplant were short interval (<7 days) between rituximab and first plasmapheresis (P = 0.004); high initial titer (≥256) (P = 0.023); low titer-reduction rate (P < 0.001); and blood group O (P < 0.001). One patient who experienced a rebound developed antibody-mediated rejection. With low-dose (200 mg) rituximab, the change in isoagglutinin titer-rebound was not significant and the infection rate was significantly decreased (P = 0.001). In conclusion, isoagglutinin titer-rebound within the first 2 weeks after KT may be a risk factor for rejection. The factors identified as affecting titer-rebound after KT were high initial isoagglutinin titer, low titer-reduction rate, short interval, and blood group O.

Excellent outcome of haploidentical hematopoietic stem cell transplantation in children and adolescents with acquired severe aplastic anemia.

We evaluated the outcome of children and adolescents with acquired severe aplastic anemia (SAA) who received haploidentical hematopoietic stem cell transplantation (HHCT) with in vitro T cell-depleted peripheral blood stem cells. Twelve patients with acquired SAA received a total of 15 HHCTs with in vitro CD3-depleted grafts between July 2009 and July 2012. Among the 12 patients, 11 achieved neutrophil engraftment at a median of 10 days (range, 9 to 13 days) after HHCT. One patient failed to achieve primary engraftment, and two experienced graft rejection soon after engraftment. All three patients who experienced early graft failure received a second HHCT and achieved sustained engraftment. Thus, the final engraftment rate was 100%. Acute graft-versus-host disease was assessed in 9 patients, excluding the 3 patients with early graft failure. Three of these patients developed acute graft-versus-host disease (two ≥ grade II and one with grade III). All 12 patients survived and were transfusion-independent at a median follow-up of 14.3 months (range, 4.1 to 40.7 months). Hematopoietic stem cell transplantation from haploidentical family donors with in vitro CD3 T cell depletion is a reasonable therapeutic option for children and adolescents with acquired SAA. Our future trial with a uniform protocol will help to solve the problems associated with HHCT and provide a valuable platform for the further development of HHCT as a therapy for SAA.

Automated double red-cell phlebotomy for the treatment of erythrocytosis.

BACKGROUND: Phlebotomy has been used as a primary method for the treatment of erythrocytosis. As a new phlebotomy method, we used an automated component collection system (Alyx, Fenwal), which has been used to obtain two units of leukoreduced red blood cells (RBCs) from donors. We evaluated the effectiveness of "double red-cell" phlebotomy (DRP) and compared it with conventional "whole-blood" phlebotomy (WBP). MATERIALS AND METHODS: We have performed a total of 596 phlebotomies in 158 patients with erythrocytosis between June 2008 and November 2011. Forty patients underwent 84 DRPs and 118 patients underwent 512 WBPs. We removed 360-420 mL of RBCs in DRP and 360-600 mL of whole blood in WBP according to patient's total blood volume (TBV). Changes in hematologic parameters after phlebotomy were compared. RESULTS: DRP removed more RBC volume (399.4 ± 20.2 mL vs. 235.9 ± 29.8 mL, P < 0.05) and lowered more hematocrit than WBP (6.9% ± 2.3% vs. 3.0% ± 1.7%, P < 0.05). Hematocrit reduction per kilogram of body weight was higher by DRP than WBP (0.106% ± 0.043% vs. 0.039% ± 0.025%, P < 0.05). Mild adverse events occurred in 32.5% (13/40) during DRP and 4.2% (5/118) during WBP. CONCLUSION: DRP lowered more RBC mass than WBP by selectively removing more RBC volume with less TBV. DRP can be an effective and safe technique for the treatment of erythrocytosis.

Combination therapy of renal cell carcinoma or breast cancer patients with dendritic cell vaccine and IL-2: results from a phase I/II trial.

BACKGROUND: Ten cancer patients (Six renal cell carcinoma and four breast cancer patients) were treated in a phase I/II study with a vaccine composed of autologous dendritic cells (DCs) and IL-2 to evaluate the DC vaccine-related toxicity and antigen-specific immune alteration. METHODS: Cancer patients were treated twice with autologous CD34+ hematopoietic stem cell-derived, GM-CSF/IFN-γ-differentiated DCs pulsed with autologous tumor lysate and KLH, by 4-week interval. Following each subcutaneous injection of therapeutic DCs, low-dose (200 MIU) IL-2 was introduced for 14 consecutive days as an immune adjuvant. To determine the DC vaccine-induced immunological alterations, the KLH-specific lymphocyte proliferation, number of IFN-γ secreting T cells (ELISPOT assay), NK activity and the cytokine modulation were measured. RESULTS: Cultured-DCs expressing HLA-DR, CD11c, CD83, and B7.1/B7.2 produced IL-12p70. After vaccination, the patients tolerated it. Clinical response was observed in one RCC patient as stable disease. However DC-vaccine related antigen-specific immune responses including peripheral blood lymphocyte proliferation and the number of IFN-r secreting cells were induced in six patients without clear correlation with clinical responses. Also NK activity was induced significantly in six patients after vaccination. DC vaccine-related decrease of TGF-ß level or increase of IL-12p70 level and decline of CD4+CD25+ T cells were observed in three patients. However only in the RCC patient whose disease stabilized, combination of stimulatory as well as inhibitory immune alterations including induction of IFN-γ secreting T cell with reduction of CD4+ CD25+ T cell were correlated with clinical responses. CONCLUSION: Data indicated that DC vaccine combined with IL-2 is well tolerated without major side effects. DC vaccine induced the specific immunity against introduced antigen. Combinatorial alterations of immunological parameters indicating antigen-specific immune induction along with reduction of inhibitory immunity were correlated with clinical responses in DC vaccine treated patients.

Dual living donor liver transplantation with ABO-incompatible and ABO-compatible grafts to overcome small-for-size graft and ABO blood group barrier.

ABO blood group compatibility has been regarded as an essential prerequisite for successful adult living donor liver transplantation (LDLT). Novel strategies for overcoming the ABO blood group barrier, however, have markedly improved the results of ABO-incompatible (ABOi) LDLT. We describe our strategies for dual graft LDLT to cope with ABO-incompatibility and small-for-size graft syndrome in 3 patients who underwent dual graft LDLT with ABOi and ABO-compatible (ABOc) grafts. One patient received a modified right lobe graft from an ABOi living donor and a left lateral section graft from an ABOc deceased donor, whereas the other 2 patients received 2 left lobe or left lateral section grafts from ABOi and ABOc living donors. To overcome the ABO-blood barrier, each patient was treated with preoperative anti-CD20 antibody (rituximab 375 mg/m(2)), perioperative plasma exchange, and hepatic arterial infusion. All 3 patients were males, of mean age 47.7 years (range, 40 approximately 52 years) and mean Model for End-Stage Liver Disease score 12.3 (range, 9 approximately 15). The mean graft-to-recipient weight ratio was 0.99%. All patients remain alive after a mean follow-up period of 9.5 months (range, 8.0 approximately 10.7 months). All 6 grafts have functioned normally. There were no episodes of antibody-mediated rejection or biliary complication. Dual LDLT with ABOi and ABOc grafts can be a feasible solution for simultaneously overcoming both the ABO blood group barrier and small-for-size graft syndrome.

The effect of VEGF on the myogenic differentiation of adipose tissue derived stem cells within thermosensitive hydrogel matrices.

We investigated the combination of human adipose tissue derived stem cells (ADSC) and in vivo gel-forming methoxy poly (ethyleneglycol)-poly (epsilon-caprolactone) (MPEG-PCL) as a muscle regeneration matrix, with and without inclusion of vascular endothelial cell growth factor (VEGF). VEGF(165)-treated stem cell grafts showed significant proliferation and differentiation into muscle tissue in vivo. Importantly, the inclusion of VEGF enhanced vascularization. This scaffold supported preconditioned ADSC, and allowed them to differentiate into mature muscle tissues in vivo, indicating that ADSC of human origin and MPEG-PCL scaffolds provided an appropriate environment for cellular growth and expansion. Our results thus provide a potential solution to the major obstacle encountered in the engineering of thick complex tissues, which require an adequate blood supply to maintain cell viability during tissue growth and to induce appropriate structural organization. Therefore, the combination of ADSC and in vivo gel-forming MPEG-PCL with VEGF(165) might serve as a suitable non-invasive biomaterial for clinical muscle regeneration applications.

Significance of donor-derived isoagglutinins in ABO-Incompatible hematopoietic stem cell transplantation.

Changes in isoagglutinin titers may have implications in the occurrence of hematological complications such as pure red cell aplasia or immune-mediated hemolysis. Furthermore, isoagglutinin titers could reflect immunohematological reconstitution after transplantation. The objective of this study was to examine the relationship between donor-derived isoagglutinins (DDIs) and graft-versus-host disease (GVHD). In total, 114 patients who underwent ABO-incompatible allogeneic hematopoietic stem cell transplantation (HSCT) were analyzed. Among these patients, 27.7% demonstrated increased donor-derived isoagglutinins (IDDIs) against red blood cells (RBCs) of the recipient, and 32.8% of the patients showed DDIs that were not against RBCs of the recipient. Patients with acute GVHD and DDIs against RBCs of the recipient tended to have higher incidences of IDDIs that occurred before posttransplant day 60 compared with patients without acute GVHD (17.3 vs. 3.9%, P=0.058). In patients with acute GVHD, IDDIs occurred significantly earlier (mean, day 32 vs. 181, P=0.046), the period of elevation was shorter (mean, day 36 vs. 134, P=0.033), and the donors were younger (mean, 28 vs. 36 years, P=0.01) than those without GVHD. Moreover, significant correlations were found between IDDIs and acute GVHD. Taken together, these data underscore a possible role for humoral immunity in GVHD after HSCT.

Establishment of a national on-line registry for apheresis in Korea.

National apheresis registries can be used to evaluate changes in technology, clinical indications, and applications over the years. Since the establishment of the Korean Society of Apheresis (KSFA) in 1999, basic data on the status of apheresis have been collected using letters and e-mails on a biennial basis. In February 2006, a KSFA homepage and an on-line apheresis registry were constructed (http://www.apheresis.or.kr/). The registry consists of two sub-registries, one addressing overall aspects, e.g., the numbers and types of apheresis machines, total numbers of apheresis procedures, and the other addressing therapeutic plasmapheresis, e.g., diagnoses, modes of treatment, instrument used, replacement fluids, volumes processed, vascular access, anticoagulants, complications, and clinical responses. Data registered on-line is presumed to represent about 95% of total apheresis procedures performed in Korea. In this report, we introduce our on-line registry system and compared the data obtained by on-line registry with the previous ones.