Clinical and molecular significance of flow cytometric analysis for reactive oxygen species production and residual p67phox expression in p67phox-deficient chronic granulomatous disease.

Chronic granulomatous disease (CGD) is a primary immunodeficiency disease caused by molecular defects in nicotinamide adenine dinucleotide phosphate (NADPH) oxidase. p67phox-CGD is an autosomal recessive CGD, which is caused by a defect in the cytosolic components of NADPH oxidase, p67phox, encoded by NCF2. We previously established a flow cytometric analysis for p67phox expression, which allows accurate assessment of residual protein expression in p67phox-CGD. We evaluated the correlation between oxidase function and p67phox expression, and assessed the relevancy to genotypes and clinical phenotypes in 11 patients with p67phox-CGD. Reactive oxygen species (ROS) production by granulocytes was evaluated using dihydrorhodamine-1,2,3 (DHR) assays. p67phox expression was evaluated in the monocyte population. DHR activity and p67phox expression were significantly correlated (r = 0.718, p < 0.0162). Additionally, DHR activity and p67phox expression were significantly higher in patients carrying one missense variant in combination with one nonsense or frameshift variant in the NCF2 gene than in patients with only null variants. The available clinical parameters of our patients (i.e., age at disease onset, number of infectious episodes, and each infection complication) were not linked with DHR activity or p67phox expression levels. In summary, our flow cytometric analysis revealed a significant correlation between residual ROS production and p67phox expression. More deleterious NCF2 genotypes were associated with lower levels of DHR activity and p67phox expression. DHR assays and protein expression analysis by using flow cytometry may be relevant strategies for predicting the genotypes of p67phox-CGD.

Regulation of HHLA2 expression in kidney cancer and myeloid cells.

BACKGROUND: The immune checkpoint HERV-H LTR-associating 2 (HHLA2) is expressed in kidney cancer and various other tumor types. Therapeutics targeting HHLA2 or its inhibitory receptor KIR3DL3 are being developed for solid tumors, including renal cell carcinoma (RCC). However, the regulation of HHLA2 expression remains poorly understood. A better understanding of HHLA2 regulation in tumor cells and the tumor microenvironment is crucial for the successful translation of these therapeutic agents into clinical applications. METHODS: Flow cytometry and quantitative real-time PCR were used to analyze HHLA2 expression in primary kidney tumors ex vivo and during in vitro culture. HHLA2 expression in A498 and 786-O ccRCC cell lines was examined in vitro and in subcutaneous tumor xenografts in NSG mice. Monocytes and dendritic cells were analyzed for HHLA2 expression. We tested a range of cytokines and culture conditions, including hypoxia, to induce HHLA2 expression. RESULTS: Analysis of HHLA2 expression revealed that HHLA2 is expressed on tumor cells in primary kidney tumors ex vivo; however, its expression gradually diminishes during a 4-week in vitro culture period. A498 and 786-O ccRCC tumor cell lines do not express HHLA2 in vitro, but HHLA2 expression was observed when grown as subcutaneous xenografts in NSG immunodeficient mice. Induction experiments using various cytokines and culture conditions failed to induce HHLA2 expression in A498 and 786-O tumor cell lines in vitro. Analysis of HHLA2 expression in monocytes and dendritic cells demonstrated that only IL-10 and BMP4, along with IL-1ß and IL-6 to a lesser extent, modestly enhanced HHLA2 protein and mRNA expression. CONCLUSIONS: HHLA2 expression is induced on kidney cancer cells in vivo by a tumor microenvironmental signal that is not present in vitro. HHLA2 expression is differentially regulated in kidney cancer epithelial cells and monocytes. Cytokines, particularly IL10, that induce HHLA2 expression in monocytes fail to upregulate HHLA2 expression in tumor cell lines in vitro. These findings underscore the importance of the interplay between tumor cell and tumor microenvironmental signals in the regulation of HHLA2. Further investigation is warranted to elucidate the mechanisms involved in HHLA2 regulation and its implications for therapeutic development.

Hematopoietic Cell Transplantation for Severe Combined Immunodeficiency Patients: a Japanese Retrospective Study.

PURPOSE: Hematopoietic cell transplantation (HCT) is a curative therapy for patients with severe combined immunodeficiency (SCID). Here, we conducted a nationwide study to assess the outcome of SCID patients after HCT in Japan. METHODS: A cohort of 181 SCID patients undergoing their first allogeneic HCT in 1974-2016 was studied by using the Japanese national database (Transplant Registry Unified Management Program, TRUMP). RESULTS: The 10-year overall survival (OS) of the patients who received HCT in 2006-2016 was 67%. Umbilical cord blood (UCB) transplantation was performed in 81 patients (45%). The outcomes of HCT from HLA-matched UCB (n = 21) and matched sibling donors (n = 22) were comparable, including 10-year OS (91% vs. 91%), neutrophil recovery (cumulative incidence at 30 days, 89% vs. 100%), and platelet recovery (cumulative incidence at 60 days, 89% vs. 100%). Multivariate analysis of the patients who received HCT in 2006-2016 demonstrated that the following factors were associated with poor OS: bacterial or fungal infection at HCT (hazard ratio (HR): 3.8, P = 0.006), cytomegalovirus infection prior to HCT (HR: 9.4, P = 0.03), ≥ 4 months of age at HCT (HR: 25.5, P = 0.009), and mismatched UCB (HR: 19.8, P = 0.01). CONCLUSION: We showed the potential of HLA-matched UCB as a donor source with higher priority for SCID patients. We also demonstrated that early age at HCT without active infection is critical for a better prognosis, highlighting the importance of newborn screening for SCID.

Investigation of risk factors associated with erythrocyte engraftment after ABO-incompatible hematopoietic stem cell transplantation.

ABO-incompatible hematopoietic stem cell transplantations (HSCTs) are widely practiced; however, the delay in erythrocyte engraftment can be problematic. While erythrocyte engraftment is usually indicated by an increase in reticulocyte levels without the need for erythrocyte transfusions, the disappearance of recipient-derived anti-A/B isoagglutinin and detection of donor-derived A/B antigens can also be used as other parameters. We conducted a retrospective analysis of 68 ABO-incompatible HSCTs, focusing on major and bidirectional mismatch. We analyzed known clinical risk factors associated with delayed erythrocyte engraftment using the three parameters (disappearance of anti-A/B isoagglutinin in recipient, detection of donor-derived A/B antigen, and reticulocyte levels >1%). Although the three parameters were well correlated, the results showed heterogeneity when analyzing the associated risk factors for delayed erythrocyte engraftment. In the analysis of all cases, the requirement for an HLA-matched platelet transfusion was a common risk factor. Furthermore, erythrocyte engraftment was slower in adults than in children. In adults, cytomegalovirus antigenemia was a risk factor for two parameters; however, in children, underlying disease was a common risk factor for all parameters. There is a complex relationship between erythrocyte engraftment and various factors related to HSCTs. Our results suggest that greater accuracy is possible by using analysis methods other than the measurement of reticulocyte levels.

Orbital Epstein-Barr virus-related post-transplant lymphoproliferative disorder in a 13-year-old girl with cord blood transplantation.

Epstein-Barr virus-associated post-transplant lymphoproliferative disorder (EBV-PTLD) is increasingly recognized as a life-threatening complication after transplantation. Most areas affected by EBV-PTLD are lymph nodes, with occasional reports of extranodal lesions such as the gastrointestinal tract and central nervous system; however, orbital regions are extremely rare. We report a case of EBV-PTLD in a cord blood transplant recipient with a tumor in the upper right eyelid. Ultimately, eye symptoms were the first signs of PTLD. Transplant physicians should consider the possibility of PTLD when encountering an orbital lesion.

Immunophenotyping of A20 haploinsufficiency by multicolor flow cytometry.

Haploinsufficiency of A20 (HA20) causes inflammatory disease resembling Behçet's disease; many cases have been reported, including some that are complicated with autoimmune diseases. This study aims to clarify the immunophenotype of patients with HA20 by analyzing lymphocyte subsets using multicolor flow cytometry. The patients with HA20 previously diagnosed in a nationwide survey were compared by their cell subpopulations. In total, 27 parameters including regulatory T cells (Tregs), double-negative T cells (DNTs), and follicular helper T cells (TFHs) were analyzed and compared with the reference values in four age groups: 0-1, 2-6, 7-19, and ≥20 years. The Tregs of patients with HA20 tended to increase in tandem with age-matched controls at all ages. In addition, patients ≥20 years had increased DNTs compared with controls, whereas TFHs significantly increased in younger patients. In HA20 patients, the increase in DNTs and TFHs may contribute to the development of autoimmune diseases.

Essential role of PTPN11 mutation in enhanced haematopoietic differentiation potential of induced pluripotent stem cells of juvenile myelomonocytic leukaemia.

We established mutated and non-mutated induced pluripotent stem cell (iPSC) clones from a patient with PTPN11 (c.226G>A)-mutated juvenile myelomonocytic leukaemia (JMML). Both types of iPSCs fulfilled the quality criteria. Mutated iPSC colonies generated significantly more CD34+ and CD34+ CD45+ cells compared to non-mutated iPSC colonies in a culture coated with irradiated AGM-S3 cells to which four growth factors were added sequentially or simultaneously. The haematopoietic differentiation potential of non-mutated JMML iPSC colonies was similar to or lower than that of iPSC colonies from a healthy individual. The PTPN11 mutation coexisted with the OSBP2 c.389C>T mutation. Zinc-finger nuclease-mediated homologous recombination revealed that correction of PTPN11 mutation in iPSCs with PTPN11 and OSBP2 mutations resulted in reduced CD34+ cell generation to a level similar to that obtained with JMML iPSC colonies with the wild-type of both genes, and interestingly, to that obtained with normal iPSC colonies. Transduction of the PTPN11 mutation into JMML iPSCs with the wild-type of both genes increased CD34+ cell production to a level comparable to that obtained with JMML iPSC colonies harbouring the two genetic mutations. Thus, PTPN11 mutation may be the most essential abnormality to confer an aberrant haematopoietic differentiation potential in this disorder.

Mosaicism of an ELANE Mutation in an Asymptomatic Mother.

PURPOSE: We report normal neutrophil count in a mother, who carries the same ELANE mutation as her daughter with severe congenital neutropenia. We hypothesized that the mother possessed wild- and mutant-type clones and the wild-type clones could generate neutrophils, whereas the mutant clones could not. METHODS: We confirmed mutant variant ratio by sequence signals and measured the frequency of the mutant allele by subcloning in various cell types. We established the ELANE-mutated and non-mutated induced pluripotent stem cells (iPSCs) from the mother's T cells and compared granulopoiesis between these iPSCs. RESULTS: In the sequence analysis of isolated peripheral blood (PB), nail and hair, the mutant variant was detected in approximately 40-60% of lymphocytes, monocytes, hematopoietic progenitor cells, and hair as well as in a small percentage of nail, but in none of the neutrophils. In the subcloning analysis of extracted DNA from CD3+ and CD34+ cells, the mutant allele was identified in 37.5% and 38.1%, respectively. We reprogrammed the mother's PB cells and established the ELANE-mutated and non-mutated iPSCs. Granulopoiesis from mutated iPSCs revealed little sensitivity to granulocyte colony-stimulating factor in comparison with non-mutated iPSCs. CONCLUSIONS: These observations strongly suggest that mutant-carrying neutrophils did not appear in the mother's PB because mutated clones could not differentiate into neutrophils. The mother's normal hematological phenotype could be explained by the perseverance of normal, non-mutated granulopoiesis.

DOCK8 mutation diagnosed using whole-exome sequencing of the dried blood spot-derived DNA: a case report of an Iraqi girl diagnosed in Japan.

BACKGROUND: Dedicator of cytokinesis 8 (DOCK8) deficiency (MIM #243700) is a rare disease, leads to a combined primary immunodeficiency (PID), and accounts for the autosomal recessive-hyper immunoglobulin E syndrome (AR-HIES). DOCK8 deficiency status characterizes by recurrent infections, atopy, and risk of cancer. Lymphoproliferative disease complicating PID, is difficult to diagnose. Our aim is to present a rare case of PID, and to the best of our knowledge, she is the first case of DOCK8 deficiency from Iraq. The genetic diagnosis was carried out in Japan using dried blood spot-based DNA transfer and whole-exome sequencing. CASE PRESENTATION: An 11-year-old Iraqi girl, of double first-cousin-parents, had a history of severe eczema, food allergy, and repeated infections. She presented with a jaw mass, bilateral cervical and axillary lymphadenopathy, and immunoglobulin (Ig) assays of 20, 3.3 and 1.7-fold above maximum normal level for age of IgE, IgA and IgG, respectively, along with a low IgM, eosinophilia and lymphopenia. Based on the jaw mass biopsy, non-Hodgkin lymphoma was suggested in Iraq, whereas histopathological re-evaluation in Japan revealed the diagnosis of a polyclonal reactive proliferation spectrum of lymphoproliferative disorders/plasmacytic hyperplasia, complicating PID. Whole-exome sequencing supported the diagnosis of PID by identifying a homozygous DOCK8 mutation with previously reported pathogenicity (NM_203447:c.3332delT, p.Phe1113Leufs*2), that may be attributed to consanguinity. CONCLUSIONS: International collaboration using an effective DNA transportation technique and next-generation sequencing was the key to pinpoint the diagnosis of DOCK8 deficiency. Our case asserted that careful pathogenetic evaluation, in an advanced setting, was crucial for ruling out the neoplastic process. Pediatricians in areas with a high prevalence of consanguinity marriage should have a high index of suspicion of DOCK8 deficiency in patients with recalcitrant eczema, and frequent respiratory and skin infectious episodes.

Prevention of transfusion-transmitted cytomegalovirus infection using leukoreduced blood components in patients receiving seronegative umbilical cord blood transplantation.

BACKGROUND: Leukoreduced blood components have been widely implemented to prevent transfusion-transmitted cytomegalovirus (TT-CMV) in transplantation. Recent progress in leukoreduction technology has helped reduce the risk of TT-CMV in hematopoietic stem cell transplantation; however, its efficacy in umbilical cord blood transplantation (CBT) has not been systematically studied. STUDY DESIGN AND METHODS: We retrospectively analyzed the incidence of CMV infection in patients treated with CBT who received prestorage leukoreduced, CMV-unselected blood components between 2007 and 2017 in a single Japanese pediatric center. Patients were monitored for CMV antigenemia at least once weekly. RESULTS: In total, 71 patients treated with CBT were identified. Two patients were excluded because of unknown CMV serostatus or early death after CBT. Of the remaining 69 patients, 24 developed CMV antigenemia. Among them, 3 received granulocyte transfusions (3 of 3; 100%), 2 were infants with severe combined immunodeficiency who had been infected with CMV before CBT (2 of 2; 100%), and 19 were CMV-seropositive patients (19 of 23, 82.6%). Conversely, of the remaining 45 patients in whom CMV antigenemia did not develop, 41 were seronegative (0 of 41; 0%) and were transfused with a total of 925 leukoreduced, CMV-unselected blood components. Among the 41 patients, 9 (22%) received in vivo T-cell depletion with antithymocyte globulin. None of the patients in the seronegative group has subsequently shown evidence of CMV infection or developed CMV disease. CONCLUSION: Using prestorage leukoreduction, no cases of CMV infection were detected in seronegative CBT patients. Our findings showed the safety of leukoreduction in preventing TT-CMV in this patient group.

Clinical and Immunological Characterization of ICF Syndrome in Japan.

OBJECTIVE: Immunodeficiency, centromeric instability, and facial anomalies (ICF) syndrome is a rare autosomal recessive primary immunodeficiency. Hypogammaglobulinemia is a major manifestation of ICF syndrome, but immunoglobulin replacement therapy does not seem to be effective for some ICF patients. Therefore, we aimed to reassess the immunological characteristics of this syndrome. METHODS: Eleven Japanese patients with ICF syndrome were enrolled. We performed whole-exome sequencing in four cases and homozygosity mapping using SNP analysis in two. We evaluated their clinical manifestations and immunological status. RESULTS: We newly diagnosed six ICF patients who had tentatively been diagnosed with common variable immunodeficiency. We identified two novel mutations in the DNMT3B gene and one novel mutation in the ZBTB24 gene. All patients showed low serum IgG and/or IgG2 levels and were treated by periodic immunoglobulin replacement therapy. Three of the six patients showed worse results of the mitogen-induced lymphocyte proliferation test. Analyses of lymphocyte subpopulations revealed that CD19+CD27+ memory B cells were low in seven of nine patients, CD3+ T cells were low in three patients, CD4/8 ratio was inverted in five patients, CD31+ recent thymic emigrant cells were low in two patients, and CD19+ B cells were low in four patients compared with those in the normal controls. ICF2 patients showed lower proportions of CD19+ B cells and CD16+56+ NK cells and significantly higher proportions of CD3+ T cells than ICF1 patients. T cell receptor excision circles were undetectable in two patients. Despite being treated by immunoglobulin replacement therapy, three patients died of influenza virus, fatal viral infection with persistent Epstein-Barr virus infection, or JC virus infection. One of three dead patients showed normal intelligence with mild facial anomaly. Two patients presented with autoimmune or inflammatory manifestations. Infectious episodes decreased in three patients who were started on trimethoprim-sulfamethoxazole and/or antifungal drugs in addition to immunoglobulin replacement therapy. These patients might have suffered from T cell immunodeficiency. CONCLUSION: These results indicate that patients with ICF syndrome have a phenotype of combined immunodeficiency. Thus, to achieve a better prognosis, these patients should be treated as having combined immunodeficiency in addition to receiving immunoglobulin replacement therapy.

Panobinostat inhibits the proliferation of CD34+ CD38- cells under stimulation of hematopoietic growth factors on AGM-S3 cells in juvenile myelomonocytic leukemia.

BACKGROUND: Encouraging responses to histone deacetylase inhibitors have been reported for hematologic malignancies. Here, we report effects of panobinostat and 5-azacytidine on the proliferation of juvenile myelomonocytic leukemia (JMML) CD34+ cells. PROCEDURE: We previously reported that stimulation of JMML CD34+ cells with stem cell factor and thrombopoietin on irradiated murine AGM-S3 cells led to substantial expansion of JMML CD34+ cells that contained leukemic stem cells capable of transplantation into immunodeficient mice. Using this culture system, we evaluated effects of panobinostat and 5-azacytidine on the proliferation of JMML CD34+ cells. RESULTS: Panobinostat dose dependently reduced the numbers of day 7 CD34+ cells generated under stimulation of hematopoietic growth factors on AGM-S3 cells in all eight patients with JMML. These patients possessed various genetic and/or karyotypic abnormalities. CD34+ CD38- cells were substantially more sensitive to panobinostat at 10 and 20 nM than CD34+ CD38+ cells. Panobinostat, however, failed to influence the ability of AGM-S3 cells to stimulate JMML CD34+ cell production. In contrast to HL60 cells, apoptosis and cell cycle arrest in panobinostat-mediated inhibition were at low levels in JMML. The inhibitor also suppressed the factor-dependent proliferation of normal CD34+ cells on AGM-S3 cells. Meanwhile, no substantial inhibitory effects of 5-azacytidine on the growth of JMML CD34+ cells were observed. CONCLUSIONS: These results demonstrate that panobinostat directly suppresses the growth of JMML CD34+ cells, in particular CD34+ CD38- cells, regardless of the genetic abnormality type, suggesting that it is a useful antileukemic drug to target JMML stem cells at a pretransplant stage.

Successful induction of therapeutic urinary concentration by intravenous ganciclovir and oral valganciclovir with remission of adenoviral hemorrhagic cystitis after cord blood transplantation.

AdV11-HC is one of the major complications after allogeneic HSCT in Japan. We previously reported that the intravenous infusion of ganciclovir was effective against AdV11-HC in a post-transplant patient. We here report a case of a 10-year-old boy who underwent cord blood transplantation for the treatment of relapsed lymphoblastic lymphoma. He developed AdV11-HC with an elevated AdV load in his urine and blood on day 14 after HSCT. He was immediately treated with intravenous ganciclovir; he rapidly achieved a remission of AdV11-HC with a decreased AdV load in his urine and blood. He remained in remission of AdV11-HC, even after we switched ganciclovir to oral valganciclovir on day 63. A pharmacokinetics study of his urine revealed that therapeutic concentrations of ganciclovir could be achieved by both intravenous ganciclovir and oral valganciclovir. These findings suggested that both intravenous ganciclovir and oral valganciclovir could be promising alternatives for the treatment of AdV11-HC in post-transplant patients.

Acute Myeloid Leukemia in a Patient With X-linked Severe Combined Immunodeficiency.

Severe combined immunodeficiency (SCID) is a defect in the differentiation and function of T cells. An increased malignancy risk, mainly lymphatic malignancy, has been described in patients with SCID. We report a patient with X-linked SCID who developed acute myeloid leukemia, derived from the recipient with somatic NRAS mutation 4 months after cord blood transplantation (CBT). Loss of heterozygosity phenomenon of the recipient at 6q14 locus was observed at 2 months post-CBT and progressed to 6q deletion (6q-) chromosome abnormality. Somatic NRAS mutation was detected at 3 months post-CBT. Thus, 6q- and NRAS mutation were strongly associated with the leukemic transformation in our patient.

Superoxide-Generating Nox5α Is Functionally Required for the Human T-Cell Leukemia Virus Type 1-Induced Cell Transformation Phenotype.

UNLABELLED: Human T-cell leukemia virus type 1 (HTLV-1) is associated with adult T-cell leukemia (ATL) and transforms T cells in vitro. To our knowledge, the functional role of reactive oxygen species (ROS)-generating NADPH oxidase 5 (Nox5) in HTLV-1 transformation remains undefined. Here, we found that Nox5α expression was upregulated in 88% of 17 ATL patient samples but not in normal peripheral blood T cells. Upregulation of the Nox5α variant was transcriptionally sustained by the constitutive Janus family tyrosine kinase (Jak)-STAT5 signaling pathway in interleukin-2 (IL-2)-independent HTLV-1-transformed cell lines, including MT1 and MT2, whereas it was transiently induced by the IL-2-triggered Jak-STAT5 axis in uninfected T cells. A Nox inhibitor, diphenylene iodonium, and antioxidants such as N-acetyl cysteine blocked proliferation of MT1 and MT2 cells. Ablation of Nox5α by small interfering RNAs abrogated ROS production, inhibited cellular activities, including proliferation, migration, and survival, and suppressed tumorigenicity in immunodeficient NOG mice. The findings suggest that Nox5α is a key molecule for redox-signal-mediated maintenance of the HTLV-1 transformation phenotype and could be a potential molecular target for therapeutic intervention in cancer development. IMPORTANCE: HTLV-1 is the first human oncogenic retrovirus shown to be associated with ATL. Despite the extensive study over the years, the mechanism underlying HTLV-1-induced cell transformation is not fully understood. In this study, we addressed the expression and function of ROS-generating Nox family genes in HTLV-1-transformed cells. Our report provides the first evidence that the upregulated expression of Nox5α is associated with the pathological state of ATL peripheral blood mononuclear cells and that Nox5α is an integral component of the Jak-STAT5 signaling pathway in HTLV-1-transformed T cells. Nox5α-derived ROS are critically involved in the regulation of cellular activities, including proliferation, migration, survival, and tumorigenicity, in HTLV-1-transformed cells. These results indicate that Nox5α-derived ROS are functionally required for maintenance of the HTLV-1 transformation phenotype. The finding provides new insight into the redox-dependent mechanism of HTLV-1 transformation and raises an intriguing possibility that Nox5α serves as a potential molecular target to treat HTLV-1-related leukemia.

Clinical and laboratory outcomes after umbilical cord blood transplantation in a patient with mucolipidosis II alpha/beta.

Mucolipidosis (ML) II alpha/beta is an autosomal recessive disease caused by reduced enzyme activity of N-acetylglucosamine-1-phosphotransferase. Clinical symptoms of ML II are severe psychomotor delay and dysostosis multiplex; death usually occurs by 5-8 years of age from cardiopulmonary complications. Allogeneic hematopoietic stem cell transplantation (HSCT) has been attempted for ML; however, few reports have documented the detailed outcomes of HSCT for ML. A 26-month-old girl received a human leukocyte antigen 3/6-allele-matched transplant from cord blood. The preparative regimen consisted of fludarabine, cyclophosphamide, 6-Gy total body irradiation, and rabbit antithymocyte globulin. Although comparing before and after cord blood transplantation results, we observed that lysosomal enzyme activities in the plasma decreased by approximately 20-40%. Low serum levels of immunoglobulin A, G2, and G4 were also observed before HSCT; however, these values normalized after transplantation. Despite undergoing HSCT, she was treated twice for bacterial pneumonia with acute respiratory distress syndrome at ages 37 and 38 months. Although HSCT effects on the clinical manifestations were limited, laboratory data including plasma lysosomal enzyme activities and serum levels of immunoglobulin showed improvement.

Markedly elevated CD64 expression on neutrophils and monocytes as a biomarker for diagnosis and therapy assessment in Kawasaki disease.

OBJECTIVE: Kawasaki disease (KD) is the most commonly encountered inflammatory disease in children. However, its pathogenesis and diagnostic biomarkers have not been fully investigated. We examined the activation of neutrophils and monocytes in KD. METHODS: We studied the expression of the Fcγ-receptors CD64 and CD16 on neutrophils and monocytes in KD before and after the treatment with intravenous infusion of high dose immunoglobulin (IVIG). Bacterial infections were addressed as well. RESULTS: CD64 expression on neutrophils and monocytes was dramatically increased at the onset of KD flare-ups, but later decreased just after IVIG. Similarly, CD16-positive monocytes were observed at the onset and were less apparent after therapy. The addition of immunoglobulin did not block the expression of CD64 or CD16 in vitro. Serum G-CSF in the majority of patients, and IFN-γ in some patients, were elevated during flares but decreased after treatment. CONCLUSION: Our findings demonstrate that remarkable CD64 expression during KD flare-ups may serve as a biomarker for diagnosis. Evaluation of CD64 is also potentially useful for the determination of treatment efficacy in KD.

Loss of Mismatched HLA on the Leukemic Blasts of Patients With Relapsed Lymphoid Malignancies Following Bone Marrow Transplantation From Related Donors With HLA Class II Mismatches in the Graft Versus Host Direction.

Mechanisms of relapse of acute lymphoblastic leukemia (ALL) after human leukocyte antigen (HLA) class II mismatched hematopoietic stem cell transplantation (HSCT) remain unclear. We report two children with relapsed ALL after HSCT from related donors with HLA-DRB1 and -DQB1 mismatches in the graft versus host direction. One lost HLA-DRB1, DQB1, and DPB1 alleles, and the other lost one HLA haplotype of the leukemic blasts at relapse. HLA class II loss may be a triggering event for ALL relapse after partially HLA-mismatched-related HSCT. In addition, HLA typing of relapsed leukemic blasts could be vital in the selection of retransplant donors.

Dramatic Improvement in the Multifocal Positron Emission Tomography Findings of a Young Adult with Chronic Granulomatous Disease Following Allogeneic Hematopoietic Stem Cell Transplantation.

Chronic granulomatous disease (CGD) is a primary immunodeficiency caused by defects of nicotinamide adenine dinucleotide phosphate oxidase. Catalase-positive bacteria and fungi are phagocytosed, but persist within phagocytes, resulting in granulomatous inflammation. Although allogeneic hematopoietic stem cell transplantation (HSCT) is a curative treatment for CGD, HSCT sometimes leads to fatal outcomes related to the exacerbation of persistent infectious or post-infectious inflammatory diseases, particularly in adolescent and young adult patients with a history of recurrent infections and/or multiple granulomas in organs. Here, we present the case of a young adult with X-linked CGD in whom multiple lesions were found in lungs and lymph nodes on both computed tomography and positron emission tomography (PET) scans before allogeneic HSCT, but all the lesions disappeared only on PET scan 5 months after HSCT. Monitoring the activity of multiple pre-existing lesions with PET scan may be beneficial to adolescent and young adult CGD-patients undergoing allogeneic HSCT.