Waldenström Macroglobulinemia and Non-IgM-Type Lymphoplasmacytic Lymphoma Are Genetically Similar.

INTRODUCTION: Waldenström macroglobulinemia (WM) represents a subset of lymphoplasmacytic lymphoma (LPL) with the immunoglobulin (Ig)M paraprotein. MYD88 L265P and CXCR4 mutations are common mutations in WM patients, and mutations in ARID1A and KMT2D (MLL2) have also been reported. However, little information has been accumulated on genetic changes in LPL with other paraproteins like IgG. METHODS: We therefore aimed to evaluate genetic differences between WM and LPL with non-IgM paraprotein (non-IgM-type LPL) using targeted next-generation sequencing (NGS) in 20 Japanese patients (10 with WM, 10 with non-IgM-type LPL). RESULTS: Mutations were detected in ARID1A (10%), CXCR4 (20%), MYD88 (90%), and KMT2D (0%) for WM patients and in ARID1A (10%), CXCR4 (20%), MYD88 (70%), and KMT2D (10%) for non-IgM-type LPL patients. No significant differences were identified. No mutations were detected in NOTCH2, PRDM1, CD274 (PD-L1), PDCD1LG2 (PD-L2), RAG2, MYBBP1A, TP53, or CD79B. DISCUSSION: Mutant allele frequency in MYD88 L265P did not differ significantly between WM and non-IgM-type LPL. Most mutations detected by NGS were subclonal following MYD88 L265P, although one non-IgM-type LPL patient harbored only CXCR4 S338X mutation. Our NGS analyses reveal genetic characteristics in LPL patients and suggest genetic similarities between these two subsets of LPL, WM and non-IgM-type.

Reduction of blood group A antigen on erythrocytes in a patient with myelodysplastic syndrome harboring somatic mutations in RUNX1 and GATA2.

BACKGROUND: Reduction of blood group ABO antigens on red blood cells (RBCs) is well known in patients with leukemias, and this reduction of ABO expression is strongly associated with DNA methylation of the ABO promoter. Previously, we reported a two-nucleotide deletion in RUNX1 encoding an abnormally elongated protein lacking the trans-activation domain in a patient with myelodysplastic syndrome (MDS) showing A-antigen loss on RBCs. This prompted us to investigate the underlying mechanism responsible for A-antigen reduction on RBCs in another patient with MDS. STUDY DESIGN AND METHODS: Screening of somatic mutations was carried out using a targeted sequencing panel with genomic DNA from peripheral blood mononuclear cells from the patient and eleven MDS controls without A- or B-antigen loss. DNA methylation of the ABO promoter was examined by bisulfite genomic sequencing. Transient transfection assays were performed for functional evaluation of mutations. RESULTS: Screening of somatic mutations showed missense mutations in RUNX1 and GATA2 in the patient, while no mutation was found in exons of those genes in the controls. There was no significant difference in ABO promoter methylation between the patient and the controls. Transient transfection experiments into COS-7 and K562 cells suggested that the amino acid substitutions encoded by those mutations reduced or lost the trans-activation potential of the ABO expression. CONCLUSION: Considering the discrepancy between the variant frequencies of these mutations and the ratios of the RBCs with A-antigens loss, the antigen reduction might be associated with these somatic mutations and hypermethylation of the ABO promoter.

Allo-anti-M: Detection peaks around 2 years of age, but may be attenuated by red blood cell transfusion.

BACKGROUND: Anti-M is frequently observed as a naturally occurring antibody of little clinical significance. Naturally occurring anti-M is often found in children although the specific triggers of production, persistence, and evanescence of anti-M have yet to be elucidated. METHODS: In a retrospective, multicenter, nationwide cohort survey conducted from 2001 to 2015, alloantibody screening was performed before and after transfusion in 18,944 recipients younger than 20 years. Recipients were categorized into six cohorts based on their age at transfusion; within and among these cohorts, allo-anti-M was analyzed in regard to its production, persistence, and evanescence. RESULTS: In 44 patients, anti-M detected before and/or after transfusion was an age-related phenomenon, with a median age of 2 years and an interquartile range of 1-3 years; anti-M was most frequently detected in a cohort of children 1 to <5 years (0.77%, 31 of 4035). At least five patients were presumed to have concurrent infections. Among 1575 adolescents/young adults (15 to <20 years), no anti-M was detected. Of 29 patients with anti-M prior to transfusion, the antibody fell to undetectable levels in 17 recipients (89.5%, of whom at least 13 received only M-negative red cells) after anywhere from 5 days to 5.8 years; anti-M persisted in 2, and was not tested in 10. Only 15 recipients (0.08%) produced new anti-M after transfusion. CONCLUSION: Naturally occurring anti-M is a phenomenon of younger ages, predominantly between 1 and 3 years. After transfusion, it often falls to undetectable levels.

Transfusion-associated circulatory overload and high blood pressure: A multicentre retrospective study in Japan.

BACKGROUND: Transfusion-associated circulatory overload (TACO) is an adverse reaction associated with a high risk of mortality. The actual incidence of TACO and hypertension associated with transfusion in Japan is unknown. METHODS: A multicentre retrospective observational study was conducted across 23 institutions during the 1-year period of 2016. Patients were included if they developed TACO or their blood pressure (either systolic or diastolic) increased by at least 30 mmHg during the transfusion. TACO was confirmed by the primary physicians and transfusion medicine teams and recorded in the data on passive surveillance, and additional data were extracted from electronic medical records. RESULTS: In our patient cohort of 31 384 patients who underwent transfusion, the incidence of TACO and hypertension was 0·03% and 0·2%, respectively. However, 43% of the participating institutions didn't report any cases. When comparing risk factors between the TACO and hypertension groups, there were significant differences in comorbidities, such as abnormal findings on chest x-ray. Significant differences between the two groups were observed post-transfusion pulse rate, body temperature and oxygen saturation (P < 0·01). In the group of patients with hypertension, the level of BNP increased significantly after transfusion in 45% (5/11) of the patients. We identified 4 patients in the hypertension group who met the new ISBT's TACO criteria. CONCLUSION: Our study suggests that more attention should be given to TACO in Japan, particularly in terms of improving surveillance systems. For the early diagnosis of TACO, it is crucial to carefully monitor vital signs including blood pressure.

RUNX1 mutation in a patient with myelodysplastic syndrome and decreased erythrocyte expression of blood group A antigen.

BACKGROUND: Loss of blood group ABO antigens on red blood cells (RBCs) is well known in patients with leukemias, and such decreased ABO expression has been reported to be strongly associated with hypermethylation of the ABO promoter. We investigated the underlying mechanism responsible for A-antigen reduction on RBCs in a patient with myelodysplastic syndrome. STUDY DESIGN AND METHODS: Genetic analysis of ABO was performed by PCR and sequencing using peripheral blood. RT-PCR were carried out using cDNA prepared from total bone marrow (BM) cells. Bisulfite genomic sequencing was performed using genomic DNA from BM cells. Screening of somatic mutations was carried out using a targeted sequencing panel with genomic DNA from BM cells, followed by transient transfection assays. RESULTS: Genetic analysis of ABO did not reveal any mutation in coding regions, splice sites, or regulatory regions. RT-PCR demonstrated reduction of A-transcripts when the patient's RBCs were not agglutinated by anti-A antibody and did not indicate any significant increase of alternative splicing products in the patient relative to the control. DNA methylation of the ABO promoter was not obvious in erythroid cells. Targeted sequencing identified somatic mutations in ASXL1, EZH2, RUNX1, and WT1. Experiments involving transient transfection into K562 cells showed that the expression of ABO was decreased by expression of the mutated RUNX1. CONCLUSION: Because the RUNX1 mutation encoded an abnormally elongated protein without a transactivation domain which could act as dominant negative inhibitor, this frame-shift mutation in RUNX1 may be a genetic candidate contributing to A-antigen loss on RBCs.

PARP1 V762A polymorphism affects the prognosis of myelodysplastic syndromes.

OBJECTIVE: Myelodysplastic syndromes (MDS), caused by various genetic mutations in hematopoietic stem cells, are associated with highly variable outcomes. Poly (ADP-ribose) polymerase-1 (PARP1) plays an important role in DNA damage repair and contributes to the progression of several types of cancer. Here, we investigated the impact of PARP1 V762A polymorphism on the susceptibility to and prognosis of MDS. METHODS: Samples collected from 105 MDS patients and 202 race-matched healthy controls were subjected to polymerase chain reaction-restriction fragment length polymorphism for genotyping. RESULTS: The allele and genotype frequencies of PARP1 V762A did not differ between MDS patients and the control group. However, MDS patients with the PARP1 V762A non-AA genotype, which is associated with high gene activity, had shorter overall survival rates (P = .01) than those with the AA genotype. Multivariate analysis of overall survival also revealed PARP1 V762A non-AA genotype as a poor prognostic factor (P = .02). When patients were analyzed according to treatment history, the PARP1 V762A non-AA genotype was only associated with poor survival in patients who had received treatment (P = .02). CONCLUSION: PARP1 V762A polymorphism may be an independent prognostic factor for MDS, and a predictive biomarker for MDS treatment.

Comparison of incidence of anaphylaxis between sugammadex and neostigmine: a retrospective multicentre observational study.

BACKGROUND: Although cases of anaphylaxis caused by sugammadex have been reported, its incidence remains uncertain. Conversely, no studies have evaluated the incidence of anaphylaxis to neostigmine. METHODS: This was a retrospective multicentre observational study of patients who underwent surgery under general anaesthesia between 2012 and 2016 to compare the incidence of anaphylaxis with sugammadex with that of neostigmine at four tertiary hospitals in Japan. To ensure the quality of diagnosis, only cases with a clinical history suggestive of anaphylaxis, along with positive results from in vitro or in vivo testing, were assessed. RESULTS: From a total of 49 532 patients who received general anaesthesia included in this study, 18 cases of anaphylaxis were reported, of which six were attributable to sugammadex and none to neostigmine. There were no fatalities attributable to anaphylaxis. The incidence of anaphylaxis caused by all drugs or by sugammadex was calculated as 0.036% (95% confidence interval [CI]: 0.022-0.057%) and 0.02% (of the number of sugammadex cases) (95% CI: 0.007-0.044%), respectively. CONCLUSIONS: The results suggest that neostigmine might be safer than sugammadex when assessing only the incidence of anaphylaxis. We believe that there is room for reconsideration of the choice of reversal agent for neuromuscular blocking agents by all anaesthetists. CLINICAL TRIAL REGISTRATION: UMIN000022365; UMIN000033561.

Prognostic impact of trisomy 21 in follicular lymphoma.

The chromosomal abnormalities associated with follicular lymphoma (FL) prognosis are not fully elucidated. Here, we evaluated the pattern of chromosomal abnormalities in FL, and clarified the correlations between the cytogenetic features and clinical outcome. Cytogenetic analysis was performed using standard methods of Giemsa-banding at diagnosis for 201 FL patients admitted to our hospitals between 2001 and 2013. The identified chromosomal abnormalities were: t(14;18)(q32;q21) (59·2%), +X (17·9%), del(6)(q)/-6 (16·9%), +7 (14·4%), abnormality of 1q12-21/1q (12·9%), del(13)(q)/-13 (11·9%), abnormality of 3q27 (10·4%), abnormality of 10q22-24 (10·0%), +12/dup(12)(q) (10·0%), abnormality of 1p21-22/1p (9·0%), +18 (9·0%), del(17)(p)/-17 (5·0%), and a complex karyotype (54·7%). Patients with trisomy 21 had a significantly shorter progression-free survival (P = 0·00171) and overall survival (OS) (P < 0·001) than those without trisomy 21; additionally, patients with trisomy 21 in the rituximab-treated cohort also had a significantly shorter OS (P = 0·000428). Multivariate analysis identified trisomy 21 as an independent risk factor in our cohorts with or without t(14;18) (P = 0·015). In conclusion, the presence of trisomy 21 was an independent risk factor for in FL. Chromosomal analysis of FL patients at diagnosis can provide useful information about their expected survival.

[Thyroid storm and exacerbation of autoimmune hemolytic anemia following childbirth].

A 32-year-old woman was diagnosed with autoimmune hemolytic anemia (AIHA) at 12 weeks of a pregnancy examination and followed up closely without treatment. At 40 weeks of gestation, she underwent emergency caesarean section because of premature rupture. On postoperative day one, the patient exhibited worsening hemolysis and tachycardia and developed high-output heart failure; she was diagnosed with Basedow disease based on the tachycardia pattern and thyroid storm based on the presence of hyperthyroidism, fever, tachycardia, and heart failure. She was administered thiamazole and potassium iodide, which improved her thyroid function, hemolytic anemia, and heart failure. AIHA is rarely associated with Basedow disease, and hemolytic anemia can be aggravated by hyperthyroidism. In pregnant women with AIHA, management of hyperthyroidism is crucial as delivery can lead to thyroid storm.

PDCD1 and CTLA4 polymorphisms affect the susceptibility to, and clinical features of, chronic immune thrombocytopenia.

Programmed death-1 (PD-1, PDCD1) and cytotoxic T lymphocyte-associated antigen-4 (CTLA-4, CTLA4) play central roles in immune checkpoint pathways. Single nucleotide polymorphisms (SNPs) of PDCD1 and CTLA4 have been reported to be associated with susceptibility to some autoimmune diseases. However, the potential association between SNPs in these immune checkpoint genes and risk of chronic immune thrombocytopenia (cITP) remain controversial and obscure. The aims of this study were to clarify the influence of PDCD1 and CTLA4 SNPs on the risk of developing cITP and its clinical features. We obtained genomic DNA from 119 patients with cITP and 223 healthy controls; their genotypes were determined by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Patients with cITP had a significantly higher frequency of the PDCD1 +7209 TT genotype compared with healthy controls. The CTLA4 -1577 GG genotype and CT60 GG genotype showed higher frequencies of platelet count <5 × 109 /l at diagnosis, minimum platelet count <5 × 109 /l, and bleeding symptoms. Moreover, the PDCD1 -606 AA genotype and +63379 TT genotype were significantly associated with a lower number of patients who achieved a complete response to prednisolone treatment. Our results suggest that the immune checkpoint polymorphisms may affect the susceptibility to the clinical features of cITP, and treatment response of the affected patients.

Clonal evolution detected with conventional cytogenetic analysis is a potent prognostic factor in adult patients with relapsed AML.

We retrospectively investigated 144 patients with relapsed acute myeloid leukemia (AML) to clarify predisposing factors and the prognostic impact of acquisition of additional cytogenetic abnormalities (ACA) at the first relapse. Additional cytogenetic abnormalities are recognized as clonal evolution at the cytogenetic level. Fifty-nine patients (41%) acquired ACA at the first relapse. The incidences of ACA acquisition varied depending on cytogenetic abnormalities at initial diagnosis. Multivariate analysis identified t(8;21), complex karyotype, and a duration of fewer than 12 months of complete remission as independent predisposing factors for ACA acquisition. Notably, patients with ACA acquisition showed a significantly lower second complete remission rate compared with those without ACA acquisition (20.0% vs 72.5%, respectively, P < .001). Furthermore, the 3-year overall survival rates after the first relapse were significantly different between patients with and without ACA acquisition (8.5% vs 36.8%, respectively, P < .001). This prognostic significance was confirmed with multivariate analysis. The hazard ratio of ACA acquisition was similar or higher than reported prognostic factors for relapsed AML patients. These findings suggested that clonal evolution detected with conventional cytogenetic analysis at the first relapse induces severe chemo-refractory characteristics in AML cells and should be considered as a potent prognostic factor when evaluating accurate prognosis in relapsed AML patients.

IL17A and IL23R gene polymorphisms affect the clinical features and prognosis of patients with multiple myeloma.

Single nucleotide polymorphisms (SNPs) in interleukin 17 (IL17A) and IL-23 receptor (IL23R) are involved in the pathogenesis of many cancers and autoimmune diseases. We investigated the influence of IL17A and IL23R SNPs on the risk of developing multiple myeloma (MM) and its clinical features. We obtained genomic DNA from 120 patients with MM and 201 healthy controls and detected IL17A -197 G/A (rs2275913) and IL23R H3Q (rs1884444) genotypes using the polymerase chain reaction-restriction fragment length polymorphism method. There were no significant differences in the genotype and allele frequencies of IL17A -197 G/A and IL23R H3Q between the controls and patients with MM. Compared with the GG and GA genotypes, the IL17A AA genotype was significantly associated with lower hemoglobin levels. The IL23R HH genotype was significantly associated with higher frequency of bone lesions and plasmacytoma than the HQ and QQ genotypes. We observed significant differences in overall survival (OS) between patients treated with thalidomide and/or bortezomib and those treated conventionally. Therefore, we also examined the effect of IL17A and IL23R polymorphisms on the clinical variables and OS in patients treated with thalidomide and/or bortezomib. We observed that the IL23R HH genotype was significantly associated with poor survival compared with the QH and HH genotypes in these patients. Our findings indicate that IL17A -197 G/A and IL23R H3Q are not associated with susceptibility to MM. However, IL-17 and IL-23R polymorphisms may affect severity, bone lesions, and extra-medullary disease in patients with MM. Moreover, IL23R polymorphisms may contribute to poor prognosis in patients with MM treated with thalidomide and/or bortezomib.

A Rare Case of Chronic Active Epstein-Barr Virus (EBV) Infection Accompanied by the Infiltration of EBV-infected CD8+ T Cells into the Muscle.

We describe a rare case of chronic active Epstein-Barr virus (CAEBV) infection, with infiltration of the skeletal muscle. A 19-year-old woman with swollen cervical lymph nodes and a fever was referred to our hospital. Swelling of the trapezium muscle and elevation of creatinine kinase level were observed. Biopsy results of the brachialis muscle revealed infiltration of Epstein-Barr virus (EBV)-encoded RNA-positive CD8 T lymphocytes. The EBV virus load in the peripheral blood was high, and EBV monoclonality was determined by Southern blot analysis. Owing to the rarity of CAEBV with skeletal muscle infiltration, this case alerts physicians to the potential diagnostic pitfalls of CAEBV.

Apheresis on aged patients/donors with complicated backgrounds like ischemic heart disease, arrhythmia, and others.

Peripheral blood stem cells (PBSCs) are currently one of the most important stem cell sources for hematopoietic stem cell transplantation as well as cell therapy for ischemic heart disease or critical limb ischemia. Thus, it is sometimes necessary to collect autologous PBSCs from donors who have comorbidities. In terms yield, a sufficient number of PBSCs can be collected from donors with comorbidities for performing cell therapy if their age is < 60 years or up to a maximum of 70 years, although the number of PBSCs collected from older donors would probably be lower than that obtained from younger donors. On the other hand, granulocyte colony-stimulating factor (G-CSF) administration sometimes results in severe adverse events (AEs), such as ischemic heart disease and vascular thrombosis. Therefore, it is very important to perform strict medical check-ups according to the standards for donor operations in each country before apheresis. The apheresis procedure and G-CSF administration should be performed after administering the appropriate treatment. There is very less information available regarding AEs related to citrate administration during apheresis in aged donors with complicated medical histories. Medical staff should have knowledge of the electrocardiogram (ECG) QTc prolongation that occurs during apheresis owing to hypocalcemia caused by citrate administration, necessitating electrocardiographic monitoring of patients. Calcium should be administered during apheresis to prevent citrate related symptoms.

Short-term administration of recombinant human erythropoietin decreases B cell number in human peripheral blood.

OBJECTIVES: There are conflicting results on the influence of recombinant human erythropoietin (rHuEPO) administration to lymphocytes, especially to B cells. METHODS: We analyzed peripheral white blood cell (WBC) subsets in patients who received one bolus administration of rHuEPO. 119 autologous blood donors were enrolled in this study. Fourty-nine out of them were treated with rHuEPO. Blood samples were obtained before the first phlebotomy and one week later before the second one. By flow cytometry, we measured the numbers of WBC, lymphocytes, dendritic cells, CD4+ T cells, CD8+ T cells, natural killer (NK) cells, B cells, monocytes, and neutrophils, further details of B cell subsets. RESULTS: In the EPO-treatment group, absolute numbers of lymphocytes, especially CD8+ T cells, NK cells, and B cells, significantly decreased after rHuEPO administration. In B cell subsets, absolute numbers of naïve B cells and IgD-CD27- B cells significantly decreased. Other B cell subsets, such as transitional B cells, memory B cells, and marginal zone B cells, also showed a decreasing trend. CONCLUSION: These findings suggest that a single administration of rHuEPO can influence human immune system via reduction of B cell number in peripheral blood.

Released washed platelet concentrates are effective and safe in patients with a history of transfusion reactions.

BACKGROUND: Plasma removal by washing is an effective approach to prevent transfusion reactions by platelet concentrates (PCs). Recently, washed PCs were released by the Japanese Red Cross Society (JRCS). MATERIALS AND METHODS: This retrospective multicenter study evaluated the efficacy and safety of released washed PCs (RWPCs) between September 2016 and January 2017 in Japan. The RWPCs were prepared by washing leukoreduced apheresis PCs with the platelet additive solution, BRS-A, using automated cell processors. RESULTS: Clinical data were obtained from 91 patients and 1210 RWPC transfusions at 50 institutions. The median number of RWPC transfusions per patient was 8 (range, 1-91). RWPCs were used in 94.5% of the patients with a history of recurrent or severe transfusion reactions for preventing such reactions. Responses of RWPCs were evaluated as complete response (91.6%), partial response (8.2%), no-change (0.2%), and progression (0%) and overall response was equal across subgroups divided by patients' profiles. The median corrected count increment (CCI) at 1 and 24 h post-transfusion were 13.5 (range, 1.9-35.4) × 109/L and 3.5 (range, -13 to 53.6) × 109/L, respectively, and median CCI at 24 h was 5.5 (range, -13 to 53.6) × 109/L in patients without risk factors associated with platelet transfusion refractoriness. Transfusion reactions to RWPCs were observed in only nine transfusions (0.7%), all of which were mild allergic reactions. CONCLUSION: This study demonstrated that RWPCs were effective and safe in patients with a history of transfusion reactions. Further prospective studies on efficacy together with cost-benefit analysis in RWPCs are needed.

Usefulness of Basophil Activation Tests for Diagnosis of Sugammadex-Induced Anaphylaxis.

BACKGROUND: Sugammadex is used to reverse the effects of neuromuscular blocking agents in many cases of general anesthesia. However, there are several reports of anaphylaxis after its use. Skin testing is the gold standard for detecting the causative agent of anaphylaxis. However, due to the lack of validated protocols for skin testing with sugammadex, the diagnostic accuracy might be inadequate. Recently, the basophil activation test (BAT) has been established as a tool to detect the causative agent of anaphylaxis with high sensitivity and specificity. However, few studies have investigated the utility of the BAT for sugammadex-induced anaphylaxis. METHODS: Eight patients who presented with immediate hypersensitivity to sugammadex during general anesthesia were included in this study. We conducted skin tests to confirm the diagnosis of sugammadex-induced anaphylaxis. Twenty-one sugammadex-naive individuals who had a negative skin test for allergy to this drug were enrolled as controls. Basophils were selected on a CD3/CRTH2 gate and labeled with CD63 and CD203c. RESULTS: The ratios of activated basophils in the patients were much higher than those in controls: the median values of areas under the curves in the patients and controls for CD203c were 1,265,985 (95% confidence interval [CI], 77,580-5,040,270) and 116,325 (95% CI, -268,605 to 232,690), respectively (Mann-Whitney U test, P < .01), and the areas under the curves in the patients and controls for CD63 were 788,647 (95% CI, 120,285-3,523,410) and 220,005 (95% CI, -50,346 to 404,680), respectively (Mann-Whitney U test, P < .01). The patients, but not controls, demonstrated clear dose-dependent CD203c upregulation. This was also true for CD63. In the case of CD203c, the sensitivity of the BAT for sugammadex was 88% (95% CI, 47%-100%), and specificity was 100% (95% CI, 84%-100%), while sensitivity and specificity for CD63 were 75% (95% CI, 35%-97%) and 100% (95% CI, 84%-100%), respectively. CONCLUSIONS: The BAT seems to have comparable accuracy to skin tests for the diagnosis of sugammadex-induced anaphylaxis. For this purpose, both CD203c and CD63 can be used to detect activated basophils.

Required cefazolin concentration to maximize diagnostic accuracy of the basophil activation test for cefazolin-induced anaphylaxis.

PURPOSE: Identifying the causative agent of perioperative anaphylaxis is key to preventing its recurrence. Besides skin testing, the basophil activation test (BAT) is increasingly being accepted as an additional and reliable method. Cefazolin seems to be a major cause of perioperative anaphylaxis. However, few studies have described use of the BAT for cefazolin-induced anaphylaxis. In this study, we aimed to determine the optimum cefazolin concentration required in the BAT for an accurate diagnosis. METHODS: Seven patients who presented with immediate hypersensitivity to cefazolin and 21 control subjects were studied. We conducted skin tests and performed BATs using both CD203c and CD63 as markers of activated basophils. We measured the ratio of activated basophils after stimulation with serial dilutions of cefazolin and investigated the cefazolin concentration that resulted in better sensitivity and specificity. RESULTS: All patients demonstrated positive reactions to cefazolin, while all control subjects showed negative reactions on skin tests. The net percentage of both CD203c- and CD63-labeled activated basophils was greater when higher concentrations of cefazolin than previously reported were used. In control subjects, however, the number of activated basophils by cefazolin stimulation was negligible regardless of its concentration. In the case of CD203c, the sensitivity was 86% with a cefazolin concentration of 3 mg/ml, while in the case of CD63, the sensitivity was 100% with a cefazolin concentration of 10 mg/ml. CONCLUSION: Using a higher concentration of cefazolin than previously reported for the BAT might increase the accuracy of diagnosis of cefazolin-induced anaphylaxis.

Overexpression of B-cell lymphoma 6 alters gene expression profile in a myeloma cell line and is associated with decreased DNA damage response.

B-cell lymphoma 6 (BCL6) attenuates DNA damage response (DDR) through gene repression and facilitates tolerance to genomic instability during immunoglobulin affinity maturation in germinal center (GC) B cells. Although BCL6 expression is repressed through normal differentiation of GC B cells into plasma cells, a recent study showed the ectopic expression of BCL6 in primary multiple myeloma (MM) cells. However, the functional roles of BCL6 in MM cells are largely unknown. Here, we report that overexpression of BCL6 in a MM cell line, KMS12PE, induced transcriptional repression of ataxia telangiectasia mutated (ATM), a DDR signaling kinase, which was associated with a reduction in γH2AX formation after DNA damage. In contrast, transcription of known targets of BCL6 in GC B cells was not affected, suggesting a cell type-specific function of BCL6. To further investigate the effects of BCL6 overexpression on the MM cell line, we undertook mRNA sequence analysis and found an upregulation in the genomic mutator activation-induced cytidine deaminase (AID) with alteration in the gene expression profile, which is suggestive of de-differentiation from plasma cells. Moreover, interleukin-6 exposure to KMS12PE led to upregulation of BCL6 and AID, downregulation of ATM, and attenuation of DDR, which were consistent with the effects of BCL6 overexpression in this MM cell line. Taken together, these results indicated that overexpression of BCL6 alters gene expression profile and confers decreased DDR in MM cells. This phenotypic change could be reproduced by interleukin-6 stimulation, suggesting an important role of external stimuli in inducing genomic instability, which is a hallmark of MM cells.

The cytokine polymorphisms affecting Th1/Th2 increase the susceptibility to, and severity of, chronic ITP.

BACKGROUND: T-helper cell type 1 (Th1) polarization in chronic immune thrombocytopenia (cITP) has been reported at the protein and mRNA levels. We evaluated the impact of Th1/Th2 cytokine and cytokine receptor functional polymorphisms on both susceptibility to, and severity of, cITP. We analysed IFN-γ + 874 T/A, IFN-γR -611G/A, IL-4 -590C/T, and IL-4Rα Q576R polymorphisms in 126 cITP patients (male/female: 34/92; median age: 47.7 years) and 202 healthy control donors. Genotyping was determined by PCR and direct sequencing. The Th1/Th2 ratio was detected in peripheral blood mononuclear cells via flow cytometry. RESULTS: cITP patients had a higher frequency of the IL-4Rα 576 non-QQ genotype compared to healthy subjects (P = 0.04). cITP patients with the IFN-γ +874 non-AA genotype (high expression type) showed more severe thrombocytopenia than those with the AA genotype (P < 0.05). cITP patients had a significantly higher Th1/Th2 ratio than control patients (P < 0.01); this ratio was inversely correlated with platelet counts. Furthermore, patients with both IFN-γ +874 non-AA genotype (high expression type) and IFN-γR -611 non-AA genotype (high-function type) had a significantly higher Th1/Th2 ratio (P < 0.05). CONCLUSIONS: The cytokine polymorphisms affecting Th1/Th2 increase the susceptibility to, and severity of, chronic ITP.