Prophylactic effect of dietary glutamine supplementation on interleukin 8 and tumour necrosis factor alpha production in trinitrobenzene sulphonic acid induced colitis

BACKGROUND

It is well established that glutamine supplemented elemental diets result in less severe intestinal damage in experimental colitis. However, few studies have examined the mode of action of glutamine in reducing intestinal damage.

AIMS

To examine the effects of glutamine supplemented elemental diets on the potent inflammatory cytokines interleukin 8 (IL-8) and tumour necrosis factor alpha (TNF-alpha) in trinitrobenzene sulphonic acid (TNBS) induced colitis which presents with both acute and chronic features of ulcerative colitis.

METHODS

Sprague-Dawley rats were randomised into three dietary groups and fed 20% casein (controls), or 20% casein supplemented with either 2% glutamine (2% Gln) or 4% glutamine (4% Gln). After two weeks they received intracolonic TNBS to induce colitis.

RESULTS

Both Gln groups of rats gained more weight than the control group (p < 0.05) which had progressive weight loss. Colon weight, macroscopic, and microscopic damage scores for the Gln groups were lower than in the control group (p < 0.05). IL-8 and TNF-alpha concentrations in inflamed colonic tissues were lower in the Gln groups than in the control group (p < 0.05), and correlated well with disease severity. Bacterial translocation was lower both in incidence (p < 0.05) and in the number of colony forming units (p < 0.05) for the Gln groups, than in the control group. With respect to all indices studied, the 4% Gln group performed better than did the 2% Gln group.

CONCLUSION

Prophylactic glutamine supplementation modulates the inflammatory activities of IL-8 and TNF-alpha in TNBS induced colitis.

Cdc42 and Rac1 regulate the interaction of IQGAP1 with beta-catenin

IQGAP1, a target of Cdc42 and Rac1 small GTPases, directly interacts with beta-catenin and negatively regulates E-cadherin-mediated cell-cell adhesion by dissociating alpha-catenin from the cadherin-catenin complex in vivo (Kuroda, S., Fukata, M., Nakagawa, M., Fujii, K., Nakamura, T., Ookubo, T., Izawa, I., Nagase, T., Nomura, N., Tani, H., Shoji, I., Matsuura, Y., Yonehara, S., and Kaibuchi, K. (1998) Science 281, 832-835). Here we investigated how Cdc42 and Rac1 regulate the IQGAP1 function. IQGAP1 interacted with the amino-terminal region (amino acids 1-183) of beta-catenin, which contains the alpha-catenin-binding domain. IQGAP1 dissociated alpha-catenin from the beta-catenin-alpha-catenin complex in a dose-dependent manner in vitro. Guanosine 5'-(3-O-thio)triphosphate (GTPgammaS).glutathione S-transferase (GST)-Cdc42 and GTPgammaS. GST-Rac1 inhibited the binding of IQGAP1 to beta-catenin in a dose-dependent manner in vitro, whereas neither GDP.GST-Cdc42, GDP. GST-Rac1, nor GTPgammaS.GST-RhoA did. The coexpression of dominant active Cdc42 with IQGAP1 suppressed the dissociation of alpha-catenin from the cadherin-catenin complex induced by the overexpression of IQGAP1 in L cells expressing E-cadherin (EL cells). Consistent with this, the overexpression of either dominant negative Cdc42 or Rac1 resulted in the reduction of E-cadherin-mediated cell adhesive activity in EL cells. These results indicate that Cdc42 and Rac1 negatively regulate the IQGAP1 function by inhibiting the interaction of IQGAP1 with beta-catenin, leading to stabilization of the cadherin-catenin complex.

Involvement of IQGAP1, an effector of Rac1 and Cdc42 GTPases, in cell-cell dissociation during cell scattering

We have previously proposed that IQGAP1, an effector of Rac1 and Cdc42, negatively regulates cadherin-mediated cell-cell adhesion by interacting with beta-catenin and by causing the dissociation of alpha-catenin from cadherin-beta-catenin-alpha-catenin complexes and that activated Rac1 and Cdc42 positively regulate cadherin-mediated cell-cell adhesion by inhibiting the interaction of IQGAP1 with beta-catenin. However, it remains to be clarified in which physiological processes the Rac1-Cdc42-IQGAP1 system is involved. We here examined whether the Rac1-IQGAP1 system is involved in the cell-cell dissociation of Madin-Darby canine kidney II cells during 12-O-tetradecanoylphorbol-13-acetate (TPA)- or hepatocyte growth factor (HGF)-induced cell scattering. By using enhanced green fluorescent protein (EGFP)-tagged alpha-catenin, we found that EGFP-alpha-catenin decreased prior to cell-cell dissociation during cell scattering. We also found that the Rac1-GTP level decreased after stimulation with TPA and that the Rac1-IQGAP1 complexes decreased, while the IQGAP1-beta-catenin complexes increased during action of TPA. Constitutively active Rac1 and IQGAP1 carboxyl terminus, a putative dominant-negative mutant of IQGAP1, inhibited the disappearance of alpha-catenin from sites of cell-cell contact induced by TPA. Taken together, these results indicate that alpha-catenin is delocalized from cell-cell contact sites prior to cell-cell dissociation induced by TPA or HGF and suggest that the Rac1-IQGAP1 system is involved in cell-cell dissociation through alpha-catenin relocalization.

Identification of a novel beta-catenin-interacting protein

Cadherin is a well-known cell-cell adhesion molecule, and it binds to beta-catenin, which in turn binds to alpha-catenin. However, little is known about the regulatory mechanism underlying the cadherin-mediated cell-cell adhesion. Here we purified two novel beta-catenin-interacting proteins with molecular masses of 180 kDa (p180) and 150 kDa (p150) from bovine brain cytosol by using glutathione S-transferase (GST)-beta-catenin affinity column chromatography. Mass spectral analysis revealed p180 to be identical to KIAA0313 which has a putative Rap1 guanine nucleotide exchange factor (GEF) domain and p150 to be the same as KIAA0705 which has a high degree of sequence similarity to the synaptic scaffolding molecule (S-SCAM), which binds beta-catenin and KIAA0313 in the yeast two-hybrid system and overlay assay, respectively (Ide et al., Biochem. Biophys. Res. Commun. 256, 456-461, 1999; Ohtsuka et al., Biochem. Biophys. Res. Commun. 265, 38-44, 1999). beta-Catenin was coimmunoprecipitated with KIAA0313 in Madin-Darby canine kidney II (MDCKII) cells, bovine brain cytosol, and EL cells. KIAA0313 and beta-catenin were partly colocalized at sites of cell-cell contact in MDCKII cells. Taken together, our data suggest that KIAA0313 associates with beta-catenin through KIAA0705 in vivo at sites of cell-cell contact.

Association of Cumulative Steroid Dose with Risk of Infection after Treatment for Severe Acute Graft-versus-Host Disease

This study aimed to characterize the incidence and risk factors of invasive fungal disease, cytomegalovirus infection, other viral diseases, and gram-negative rod infection after glucocorticoid treatment for severe acute graft-versus-host disease (GVHD) after allogeneic hematopoietic cell transplantation and to elucidate the associations of cumulative steroid dose with the risks of individual infections. The study cohort included 91 consecutive patients who developed maximum grades III and IV acute GVHD at our center. The mean cumulative prednisolone-equivalent dose was 41 mg/kg during the first 4 weeks. The cumulative incidence rates of fungal disease, cytomegalovirus disease, other viral diseases, and gram-negative rod infection at 6 months after glucocorticoid treatment were remarkably high, at 14%, 21%, 28%, and 20%, respectively. GVHD within 26 days after transplantation and low lymphocyte count at GVHD treatment were associated with increased risks of several infections. Cumulative prednisolone-equivalent steroid doses ≥ 55 mg/kg during the first 4 weeks were associated with an increased risk of fungal disease (hazard ratio, 3.65; P = .03) and cumulative doses ≥ 23 mg/kg were associated with an increased risk of non-cytomegalovirus viral diseases (hazard ratio, 4.14; P = .02). Strategies to reduce the risk of infectious complications are needed, particularly for patients who have risk factors and those who receive high cumulative steroid doses.

Nucleoside-nucleotide free diet protects rat colonic mucosa from damage induced by trinitrobenzene sulphonic acid

BACKGROUND

Growing evidence suggests that intestinal recovery from injury induced by radiation, endotoxin, and protein deficiency is improved by the ingestion of nucleosides and nucleotides.

AIM

This study examined the effect of dietary nucleosides and nucleotides supplementation on trinitrobenzene sulphonic acid induced colonic damage in experimental colitis.

METHODS

Sprague-Dawley rats were randomised into two groups and fed nucleic acid free 20% casein diet (control) or this diet supplemented with 0.5% nucleoside-nucleotide mixture for four weeks. On the second week, colonic inflammation was induced in rats by intracolonic administration of 0.25 ml of 50% ethanol containing 25 mg of trinitrobenzene sulphonic acid. Additionally, other sets of rats were treated with 0.25 ml of 50% ethanol, 25 mg of trinitrobenzene sulphonic acid in 0.25 ml saline, or 0.25 ml of 0.9% saline.

RESULTS

After two weeks, colon weight, macroscopic and microscopic damage scores, were significantly greater (p < 0.05) in the nucleoside-nucleotide supplemented group compared with the non-supplemented control groups. The same variables seen in the trinitrobenzene sulphonic acid-ethanol group fed nucleoside-nucleotide free diet were greater (p < 0.05) than in the rest of the groups fed nucleoside-nucleotide free diet and treated with ethanol, trinitrobenzene sulphonic acid in saline, or saline. Histologically, segmental ulceration and inflammation associated with significantly increased infiltration of polymorphonuclear leucocytes, macrophages, lymphocytes, fibroblasts were observed in the supplemented group compared with the controls. In the nucleoside-nucleotide supplemented group the epithelial damage, mucosal erosion, oedema, and coagulative necrosis of the muscularis propria was more extensive in comparison to the non-supplemented control groups.

CONCLUSIONS

This study suggests that dietary nucleosides and nucleotides may aggravate colonic damage and inflammation in chemically induced experimental colitis in rats; and that nucleoside-nucleotide free diet combined with other pharmacological agents may offer a better response.

Nucleoside-nucleotide-free diet suppresses cytokine production and contact sensitivity responses in rats with trinitrobenzene sulphonic acid-induced colitis

We examined the effects of dietary nucleoside-nucleotide mixture on synthesis of inflammatory cytokines, interleukin-8 and tumor necrosis factor-alpha, in sensitized and nonsensitized colitic rats. Sensitized and nonsensitized colitic rats that were fed a nucleoside-nucleotide mixture had greater colonic weight and macroscopic and microscopic damage scores than nucleoside-nucleotide-free sensitized and nonsensitized colitic rats. Increased colonic tumor necrosis factor-alpha and interleukin-8 concentrations were associated with increased colonic inflammation and ulceration in the nucleoside-nucleotide mixture-fed group. There was also increased ear thickness in the nucleoside-nucleotide mixture-fed sensitized and nonsensitized colitic rats, which correlated highly with increased tumor necrosis factor-alpha and interleukin-8 levels in the ear lobes. Nucleoside-nucleotide-free diets may suppress cytokine secretion, thereby reducing colonic damage and contact sensitivity responses in colitic rats.

Redefining the Foreign Antigen and Self-Driven Memory CD4+ T-Cell Compartments via Transcriptomic, Phenotypic, and Functional Analyses

Under steady-state conditions, conventional CD4⁺ T lymphocytes are classically divided into naïve (CD44^lo CD62L^hi) and memory (CD44^hi CD62L^lo) cell compartments. While the latter population is presumed to comprise a mixture of distinct subpopulations of explicit foreign antigen (Ag)-specific “authentic” memory and foreign Ag-independent memory-phenotype (MP) cells, phenotypic markers differentially expressed in these two cell types have yet to be identified. Moreover, while MP cells themselves have been previously described as heterogeneous, it is unknown whether they consist of distinct subsets defined by marker expression. In this study, we demonstrate using combined single-cell RNA sequencing and flow cytometric approaches that self-driven MP CD4⁺ T lymphocytes are divided into CD127^hi Sca1^lo, CD127^hi Sca1^hi, CD127^lo Sca1^hi, and CD127^lo Sca1^lo subpopulations that are Bcl2^lo, while foreign Ag-specific memory cells are CD127^hi Sca1^hi Bcl2^hi. We further show that among the four MP subsets, CD127^hi Sca1^hi lymphocytes represent the most mature and cell division-experienced subpopulation derived from peripheral naïve precursors. Finally, we provide evidence arguing that this MP subpopulation exerts the highest responsiveness to Th1-differentiating cytokines and can induce colitis. Together, our findings define MP CD4⁺ T lymphocytes as a unique, self-driven population consisting of distinct subsets that differ from conventional foreign Ag-specific memory cells in marker expression and establish functional relevance for the mature subset of CD127^hi Sca1^hi MP cells.

Behavior of 3,4-endiol form of 2,3-diketo-gulono-delta-lactone formed from dehydro-L-ascorbic acid in deoxygenated and neutral solution

The formation of L-ascorbic acid (AsA) was observed when dehydro-L-ascorbic acid (DHA) was dissolved in neutral buffer solutions under N2 bubbling at room temperature. The reduction of DHA was done with the lactonized compound of 2,3-diketo-L-gulonic acid (DKG), that is, the 3,4-endiol form of 2,3-diketo-gulono-delta-lactone (3,4-End DKGL). 3,4-End DKGL was formed from DHA or DKG (yield about 10%) under N2 bubbling in neutral buffer solution (pH 7.2). This material was not stable in neutral or alkaline solutions. 3,4-End DKGL suppressed more strongly the linoleic acid (LA) peroxidation in the medium containing 20% EtOH and 10 mM LA than did AsA. This may suggest the possibility that 3,4-End DKGL reproduces AsA from DHA in physiological status.

Association of CD204+ macrophages with poor outcomes of malignant lymphomas not in remission treated by allogeneic HCT

OBJECTIVE

CD204⁺ tumor-associated macrophages are associated with adverse outcomes of various malignancies. We performed a study to elucidate the role of CD204⁺ macrophages in allogeneic hematopoietic cell transplantation (allogeneic HCT).

METHODS

In a total of 81 patients who received allogeneic HCT for non-remission malignant lymphoma, immunohistochemical staining of CD204 using specimens preserved before allogeneic HCT was performed. According to the average number of CD204⁺ macrophages in a high-power field, patients were categorized into three groups: low (<25th percentile), intermediate (≥25th percentile and <50th percentile), and high (≥50th percentile).

RESULTS

The B-cell lymphoma proportion was higher in the low group, while T-cell lymphoma and adult T-cell leukemia proportions were higher in the high group. The 3-year overall survival (OS) was poorest in the high group; low vs intermediate vs high = 83.3% vs 43.7% vs 20.2% (P < .01). The 3-year cumulative incidences of relapse were significantly higher in the high group than the intermediate and low groups: 67.0% vs 38.1% vs 18.2% (P < .01). In multivariate analyses, the numbers of CD204⁺ macrophages were independent risk factors of poorer OS and cumulative incidences of relapse.

CONCLUSIONS

CD204⁺ macrophages might be associated with poorer prognosis in allogeneic HCT for malignant lymphomas.

Clinical impact of hyperglycemia on days 0-7 after allogeneic stem cell transplantation

In order to clarify the association between hyperglycemia during the early period after allogeneic stem cell transplantation (allo-SCT) and adverse outcomes, we retrospectively analyzed 563 consecutive patients who underwent allo-SCT at our institute between 2008 and 2015. Patients were categorized into three groups according to mean fasting blood glucose levels on days 0-7 (normoglycemia group<110 mg/dL, n=347; mild hyperglycemia group 110-149 mg/dL, n=192 and moderate/severe hyperglycemia group≥150 mg/dL, n=24). The median follow-up was 2.7 years. Patients in the moderate/severe hyperglycemia group had significantly worse characteristics. The cumulative incidences of 2-year non-relapse mortality (NRM) and the probabilities of 2-year overall survival (OS) in the normoglycemia, mild hyperglycemia and moderate/severe hyperglycemia groups were 7.5%, 19% and 29%, respectively (P<0.01), and 69%, 53% and 33%, respectively (P<0.01). In multivariate analyses, hyperglycemia was an independent predictor of high NRM (vs normoglycemia; mild hyperglycemia, hazard ratio (HR) 2.56, 95% confidence interval (CI) 1.56-4.18; moderate/severe hyperglycemia, HR 4.46, 95% CI 1.92-10.3) and poor OS (vs normoglycemia; mild hyperglycemia, HR 1.54, 95% CI 1.14-2.07; moderate/severe hyperglycemia, HR 1.61, 95% CI 0.89-2.91). In conclusion, hyperglycemia on days 0-7 after allo-SCT was associated with inferior outcomes.

Disseminated intravascular coagulation induced by generalized cytomegalic inclusion disease during steroid therapy for polymyositis

A 56-year-old woman came to the hospital with fever and skin eruptions. A rise in myogenic enzyme and the presence of antileucocyte antibody were noticed, along with the gradual appearance of myalgia in both lower extremities, and muscle weakness. Steroid therapy was started under the diagnosis of polymyositis. The steroid was reduced because of mental disturbance but immediately the patient developed high fever. Various forms of treatment were carried out but there was no improvement, and the patient died. At autopsy there were scattered purpura on the skin, and the muscles were atrophic and yellowish-grey in color. Histopathologically, there was inflammatory cell infiltration and muscle fiber degeneration visible in many of the muscles, and the findings showed evidence of polymyositis. There were intranuclear inclusions in the lungs, ovaries, and adrenal glands, and this was diagnosed as generalized cytomegalic inclusion disease. Fibrin thrombi were found in the kidneys, lungs, and adrenal glands and this was pathologically diagnosed as disseminated intravascular coagulation. Endothelial cell damage caused by cytomegalovirus was assumed to be involved to a large extent in triggering the disseminated intravascular coagulation.

BK Virus-Associated Urothelial Carcinoma in a Patient with Peripheral Blood Stem Cell Transplantation for Acute Lymphoblastic Leukemia: A Case Report

Bladder tamponade due to hemorrhagic cystitis caused by BK virus in immunocompetent patients is familiar to urologists. BK virus is an important cause of nephropathy and graft loss in kidney transplant recipients. Although urothelial carcinoma of the bladder in kidney transplant recipients with persistent BK viruria is known, BK virus-associated urothelial carcinoma (BKVUC) in peripheral blood stem cell transplantation recipients is not as well known. A 54-year-old man with acute lymphoblastic leukemia was treated in the Department of Hematology of our hospital. After recurrence 25 months later, he received chemotherapy for half a year and underwent peripheral blood stem cell transplantation. He achieved temporarily complete remission, but he developed hematuria with BK virus-positive result 1 month after peripheral blood stem cell transplantation. One month later, he developed bladder tamponade-diagnosed hemorrhagic cystitis due to BK virus in our Urological Department. We performed transurethral coagulation to manage hemorrhage and removed a bleeding lesion in the bladder wall. Pathological examination of the removed bladder wall revealed pT1 stage BKVUC. We found that bladder tamponade could have led to reactivation of BK virus in this immunocompetent patient. This could be the first report of BKVUC of the bladder found in a peripheral blood stem cell transplantation recipient with close urological follow-up for 24 months. Adequate removal of bleeding lesions from the bladder mucosa with appropriate timing during hemorrhagic cystitis due to BKVUC could be essential to achieve good outcomes.

Characterization of readmission after allogeneic hematopoietic cell transplantation

To elucidate the incidence, causes, and risk factors associated with readmission due to transplant-related complications, we studied 213 consecutive patients who were discharged without progression of primary disease after their first allogeneic hematopoietic cell transplantation at our center between 2013 and 2016. The median patient age was 50 years (range, 18-71 years). Eighty-three patients had AML or MDS, 66 had lymphoma, 28 had ALL, 23 had ATL, and 13 had other diseases. The median duration of hospitalization for transplantation was 56 days (range 27-325 days). The cumulative incidences of readmission due to transplant-related complications were 8% at 30 days, 16% at 100 days, and 25% at 1 year after discharge. The most frequent cause of readmission was infection, followed by graft-versus-host disease throughout the first year. In multivariate analysis, steroid use at discharge was the only risk factor associated with readmission within 30 days, and steroid use at discharge, absolute lymphocyte count < 500/µl at discharge, and documented bacterial infection during admission were risk factors associated with readmission within 1 year. Our results indicated that factors during hospitalization or discharge, but not at transplantation, were associated with readmission. Patients with these risk factors should be monitored carefully after discharge.

IL-12 derived from CD8α+ dendritic cells drives the differentiation of innate-like T-bethigh memory-phenotype CD4+ T lymphocytes in steady state

CD4+ T lymphocytes consist of naïve, antigen-specific memory, and memory-phenotype (MP) cell compartments in steady state. We recently showed that MP cells exert innate-like effector function in host defense. However, it remained to be defined whether MP cell population comprises multiple subsets, and if so, what factors determine their selective differentiation under homeostatic conditions. Here we characterize MP lymphocytes as consisting of T-bethigh, T-betlow, and T-bet− subsets, with innate Th1-like effector activity exclusively associated with T-bethigh cells. We further show that steady-state differentiation of T-bethigh MP cells is promoted by IL-12-producing CD8α+ dendritic cells (DC1). Finally, we present evidence arguing that this tonic IL-12 production requires TLR-MyD88 signaling triggered independently of foreign agonists and is further enhanced by CD40-CD40L interactions with self-dependent MP CD4+ T lymphocytes. Thus, optimal differentiation of T-bethigh MP lymphocytes in steady state requires IL-12 tonically produced by DC1 in an MyD88 and CD40 signaling-dependent fashion.

This work was in part supported by the Intramural Research Program of the NIAID and NCI, NIH.

Excess generation and activation of naturally arising memory-phenotype CD4+ T lymphocytes are inhibited by regulatory T cells in steady state

Conventional CD4+ T lymphocytes consist of naïve, foreign antigen-specific memory, and self-antigen-driven memory-phenotype (MP) cell compartments at homeostasis. We recently showed that MP cells tonically proliferate in response to self-antigens and differentiate into the T-bet+ subset in steady state. How excess proliferation and differentiation of MP cells are inhibited remains unclear. Given immunosuppressive function of regulatory T cells (Tregs), it is possible that they are also involved in inhibition of spontaneous MP cell activation. Here we show using Foxp3-diphtheria toxin receptor-transgenic mice that both MP and naïve CD4+ T cells spontaneously proliferate and differentiate into Th1 cells upon acute Treg depletion. At an early time point post Treg depletion, MP as compared to naïve CD4+ T cells are preferentially activated while at a later stage, the response is dominated by activated cells originated from the naïve pool. Moreover, we argue that MP cell proliferation is driven by TCR and CD28 signaling whereas Th1 differentiation mediated by IL-2. Furthermore, our data indicate that such activation of MP and naïve CD4+ T lymphocytes contribute to development of multi-organ inflammation at early and later time points, respectively, after Treg ablation. Together our findings reveal that Tregs tonically inhibit early, spontaneous proliferation and Th1 differentiation of MP CD4+ T lymphocytes as well as late activation of naïve cells, thereby contributing to maintenance of T cell homeostasis.

Kinetics of neutrophil engraftment in allogeneic stem cell transplantation

Primary graft failure is a lethal complication that occurs after allogeneic stem cell transplantation (allo-SCT) and requires retransplantation. We retrospectively assessed 1,355 patients who underwent allo-SCT at our institute. Following allo-SCT, the cumulative incidence of subsequent neutrophil engraftment was calculated each day after day 5 among patients with white blood cell (WBC) count<100 cells/μL on the respective day. The number of patients with WBC count<100 cells/μL at days 14, 21, and 28 were 372, 55, and 21, respectively. In patients with WBC count<100 cells/μL on day 14, the cumulative incidence of engraftment was lower in recipients of peripheral blood stem cells (PBSCs) and cord blood (CB) compared with recipients of bone marrow (BM) (BM vs. PBSCs vs. CB, 93% vs. 79% vs. 77%, P<0.01). In patients with WBC count<100 cells/μL after day 14, the cumulative incidence of engraftment in recipients of PBSCs became progressively lower (25% at day 21 and 0% at day 28). In patients with WBC count<100 cells/μL on day 28, the cumulative incidence of engraftment was 100% in patients with donor chimerism≥95%, while it was only 13% in those with chimerism<95% (P<0.01). These data provide important information that could be useful in deciding the appropriate time for performing tests in patients with donor chimerism and in those that require retransplantation.

Angioimmunoblastic T-cell lymphoma harboring a t(8;14)(q24;q11.2)/TCR::MYC translocation that presented with intestinal infiltration

Although rearrangement of the MYC oncogene (MYC-R) is frequently observed in aggressive B-cell lymphomas, it is extremely rare in T-cell malignancies. A 64-year-old man who had been under observation for several years because of asymptomatic pulmonary extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALToma) was admitted to our hospital because of poor general condition and hypotension. Blood tests revealed thrombocytopenia and elevated serum lactate dehydrogenase levels, whereas computed tomography revealed systemic lymphadenopathy and splenomegaly. An inguinal lymph node biopsy precipitated a diagnosis of angioimmunoblastic T-cell lymphoma (AITL). Shortly after admission, the patient experienced spontaneous intestinal perforation and hemorrhage caused by multiple intestinal infiltrations of the AITL. Although chemotherapy was administered, the patient died several weeks after admission. A 46,XY,t(8;14)(q24;q11.2) karyotype was identified, and fluorescence in situ hybridization analyses showed split signals for the MYC and T-cell receptor (TCR) alpha genes, by which a TCR::MYC translocation was confirmed. Pathological autopsy analysis revealed systemic infiltration of the AITL and no MALToma lesions. Only a few cases of mature T-cell lymphoma harboring MYC-R have been reported in the literature thus far. To the best of our knowledge, this is the first reported case of AITL with TCR::MYC rearrangement. This condition could be associated with refractoriness to chemotherapy and aggressive clinical course with systemic infiltration that included the intestine.

Successful Cord Blood Transplantation for Myeloid/Natural Killer Precursor Acute Leukemia: A Case Report and Literature Review

A 21-year-old man was diagnosed with myeloid/natural killer precursor leukemia (MNKPL) with bone marrow infiltration of blasts of cyCD3+, CD7+, CD33+, CD34dim, CD56+/-, HLA-DR+, cyMPO+, and TdT- immunophenotypes. Although hyper-CVAD therapy was unsuccessful, induction treatment with idarubicin and cytarabine resulted in complete remission (CR). The patient subsequently underwent cord blood transplantation with a myeloablative conditioning regimen, which resulted in durable CR and complete donor chimerism. He had been in good health without relapse for over nine months since transplantation. Timely allogeneic hematopoietic stem cell transplantation using an available donor source may be a promising treatment strategy for MNKPL.

Naturally arising memory-phenotype CD4+ T lymphocytes contain an undifferentiated population that can generate TH1, TH17, and Treg cells

Memory-phenotype (MP) CD4+ T lymphocytes develop from naïve cells via self-recognition at homeostasis. While previous studies defined MP cells as a heterogeneous population that comprises T helper 1 (TH1)/17-like subsets, functional significance of the T-bet- Rorγt- subpopulation remains unknown. Here we show that MP lymphocytes as a whole population can differentiate into TH1/17/regulatory T (Treg) cells to mediate mild and persistent inflammation in lymphopenic environments, whereas naïve cells exhibit strong, TH1-dominated responses. Moreover, we demonstrate that MP lymphocytes comprise not only TH1/17-differentiated subsets but a polyclonal, transcriptomically immature "undifferentiated" subpopulation at homeostasis. Furthermore, our data argue that while the T-bet+ Rorγt- MP subset is terminally TH1-differentiated, its undifferentiated counterpart retains the capacity to rapidly proliferate to differentiate into TH1/17/Treg cells, with the latter response tonically constrained by preexisting Treg cells. Together, our results identify undifferentiated MP CD4+ T lymphocytes as a unique precursor that has a diverse differentiation potential to generate TH1/17/Treg cells to contribute to pathogenesis of inflammation.