Effects of empagliflozin on progression of chronic kidney disease: a prespecified secondary analysis from the empa-kidney trial

BACKGROUND

Sodium-glucose co-transporter-2 (SGLT2) inhibitors reduce progression of chronic kidney disease and the risk of cardiovascular morbidity and mortality in a wide range of patients. However, their effects on kidney disease progression in some patients with chronic kidney disease are unclear because few clinical kidney outcomes occurred among such patients in the completed trials. In particular, some guidelines stratify their level of recommendation about who should be treated with SGLT2 inhibitors based on diabetes status and albuminuria. We aimed to assess the effects of empagliflozin on progression of chronic kidney disease both overall and among specific types of participants in the EMPA-KIDNEY trial.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA), and included individuals aged 18 years or older with an estimated glomerular filtration rate (eGFR) of 20 to less than 45 mL/min per 1·73 m2, or with an eGFR of 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher. We explored the effects of 10 mg oral empagliflozin once daily versus placebo on the annualised rate of change in estimated glomerular filtration rate (eGFR slope), a tertiary outcome. We studied the acute slope (from randomisation to 2 months) and chronic slope (from 2 months onwards) separately, using shared parameter models to estimate the latter. Analyses were done in all randomly assigned participants by intention to treat. EMPA-KIDNEY is registered at ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and then followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroups of eGFR included 2282 (34·5%) participants with an eGFR of less than 30 mL/min per 1·73 m2, 2928 (44·3%) with an eGFR of 30 to less than 45 mL/min per 1·73 m2, and 1399 (21·2%) with an eGFR 45 mL/min per 1·73 m2 or higher. Prespecified subgroups of uACR included 1328 (20·1%) with a uACR of less than 30 mg/g, 1864 (28·2%) with a uACR of 30 to 300 mg/g, and 3417 (51·7%) with a uACR of more than 300 mg/g. Overall, allocation to empagliflozin caused an acute 2·12 mL/min per 1·73 m2 (95% CI 1·83-2·41) reduction in eGFR, equivalent to a 6% (5-6) dip in the first 2 months. After this, it halved the chronic slope from -2·75 to -1·37 mL/min per 1·73 m2 per year (relative difference 50%, 95% CI 42-58). The absolute and relative benefits of empagliflozin on the magnitude of the chronic slope varied significantly depending on diabetes status and baseline levels of eGFR and uACR. In particular, the absolute difference in chronic slopes was lower in patients with lower baseline uACR, but because this group progressed more slowly than those with higher uACR, this translated to a larger relative difference in chronic slopes in this group (86% [36-136] reduction in the chronic slope among those with baseline uACR <30 mg/g compared with a 29% [19-38] reduction for those with baseline uACR ≥2000 mg/g; ptrend<0·0001).

INTERPRETATION

Empagliflozin slowed the rate of progression of chronic kidney disease among all types of participant in the EMPA-KIDNEY trial, including those with little albuminuria. Albuminuria alone should not be used to determine whether to treat with an SGLT2 inhibitor.

FUNDING

Boehringer Ingelheim and Eli Lilly.

Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial

BACKGROUND

The EMPA-KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62-0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16-1·59), representing a 50% (42-58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all >0·1).

INTERPRETATION

In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease.

FUNDING

Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council.

[Successful treatment with brentuximab vedotin maintenance therapy after autologous stem cell transplantation in high-risk Hodgkin lymphoma]

A 56-year-old woman was diagnosed with classical Hodgkin lymphoma in December 2012. She achieved complete remission (CR) with six cycles of adriamycin, bleomycin, vinblastine, and dacarbazine (ABVD). In March 2015, she experienced a relapse marked by high fever, respiratory discomfort, and pain in the left thigh owing to tumor involvement of the femur. She was treated with one cycle of brentuximab vedotin (BV), followed by irradiation of the left femoral lesion. She achieved partial remission (PR) but developed recurrence after the third cycle of BV. She achieved PR again with two cycles of standard bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone (BEACOPP) regimen; therefore, autologous stem cell transplantation (ASCT) was performed. Because the dosing interval used for BV therapy was longer than that in the recommended schedule, we could not definitively attribute her recurrence to BV resistance. Moreover, she maintained a good performance status after recurrence during subsequent cycles of BV therapy. Because of attaining PR after ASCT, she subsequently received a total of 12 BV cycles for consolidation. She achieved CR 3 months after ASCT and has remained in CR until 29 months. For patients who show relapse after initial BV therapy, retreatment with BV should be carefully considered. Patients who show relapse after achieving at least PR with initial BV therapy are potential candidates for post-ASCT BV maintenance therapy to reduce their tumor burden.

Changes in the expression of α-tocopherol-related genes in liver and mammary gland biopsy specimens of peripartum dairy cows

Blood α-tocopherol (α-Toc) concentrations decline gradually throughout the prepartum period, reaching the nadir after calving in dairy cows. The 6 α-Toc-related molecules [α-Toc transfer protein (TTPA); afamin; scavenger receptor class B, Type I; ATP-binding cassette transporter A1; tocopherol-associated protein (SEC14L2); and cytochrome P450 family 4, subfamily F, polypeptide 2 (CYP4F2)] are expressed in liver and other peripheral tissues. These molecules could regulate α-Toc transport, blood concentrations, and metabolism of α-Toc. Therefore, the aim of this study was to evaluate the changes in the expression of α-Toc-related genes in liver and mammary gland tissues of dairy cows around calving, which have remained elusive until now. In experiment (Exp.) 1, 28 multiparous Holstein cows were used (from -5 to 6 wk relative to parturition) to monitor the changes in dietary α-Toc intake, blood concentrations of α-Toc, and lipoproteins; in Exp. 2, 7 peripartum Holstein cows were used (from -4 to 4 wk relative to parturition) for liver tissue biopsy; and in Exp. 3, 10 peripartum Holstein cows were used (from -8 to 6 wk relative to parturition) to carry out the mammary gland tissue biopsy and milk sampling. In Exp. 1, the serum α-Toc concentrations declined gradually with decreasing amount of α-Toc intake and plasma high-density lipoprotein concentrations toward calving time. However, in the early lactation period after calving, serum α-Toc concentrations remained at a lower concentration despite the recovery of α-Toc intake and plasma high-density lipoprotein concentrations. In Exp. 2, just after calving, the TTPA, SEC14L2, afamin, and albumin mRNA expression levels in the liver were temporarily downregulated, and the hepatic mRNA levels of endoplasmic reticulum stress-induced unfolded protein response markers and acute-phase response marker increased at calving. In Exp. 3, the concentrations of α-Toc in colostrum were greater than those in precolostrum (samples were collected at wk -1 relative to parturition) and mature milk. The expression of TTPA, SEC14L2, and CYP4F2 mRNA in bovine mammary gland tissue was detected. However, TTPA and SEC14L2 mRNA expressions showed the opposite trends: the expression levels of TTPA mRNA peaked whereas SEC14L2 mRNA reached a nadir at calving. These results indicate that the expression of α-Toc-related genes involved in specific α-Toc transfer and metabolism in the liver and mammary gland are altered during calving. Moreover, these changes might be associated with the maintenance of lower serum α-Toc concentrations after calving.

Effects of altering total mixed ration conservation method when feeding dry-rolled versus steam-flaked hulled rice on lactation and digestion in dairy cows

We evaluated the effects of different methods of conserving the total mixed ration (TMR) and processing hulled rice (Oryza sativa L.) on intake, digestion, ruminal fermentation, lactation performance, and nitrogen utilization in dairy cows. Eight multiparous Holstein cows (126 ± 19 d in milk) were used in a replicated 4 × 4 Latin square design with a 2 × 2 factorial arrangement of dietary treatments. The experimental diets used fresh TMR and ensiled TMR containing either dry-rolled (DR) hulled rice or steam-flaked (SF) hulled rice. The fresh TMR was prepared every morning. The ensiled TMR was prepared by baling fresh TMR and then sealing it with a bale wrapper; this was stored outdoors at 10 to 30°C for >4 mo. The method of grain processing did not affect the dry matter (DM) intake. The DM intake tended to be greater for ensiled TMR than for fresh TMR. Apparent total-tract DM digestibility and milk yield were increased by feeding ensiled TMR instead of fresh TMR and by replacing DR with SF. An interaction effect between the TMR conservation method and the grain processing method was detected for DM digestibility and milk yield; replacing DR with SF increased the DM digestibility and milk yield in cows fed fresh TMR, but this did not affect the cows fed ensiled TMR. The milk fat and lactose contents did not differ among dietary treatments. The milk protein concentration was higher for the cows fed SF processed hulled rice than those fed DR, but it was not influenced by the TMR conservation method. The ruminal total volatile fatty acid concentration was higher for the cows fed ensiled TMR compared with those fed fresh TMR, but it was not affected by the grain processing method. The molar proportion of acetate was decreased and propionate was increased by feeding ensiled TMR instead of fresh TMR and by replacing DR with SF. The concentrations of rumen ammonia N and plasma urea N were higher for the cows fed ensiled TMR than fresh TMR and were lower for SF than DR. Feeding ensiled TMR instead of fresh TMR increased the cows' urinary N excretion and decreased the retention N. Replacing DR with SF decreased the urinary N excretion, increased the milk N secretion, and then improved the nitrogen efficiency. These results show that feeding ensiled TMR instead of fresh TMR has an adverse effect on N utilization, but it increases digestion and milk production. Replacing DR with SF also increases digestion, milk yield, and milk protein content, and the improvement of milk yield by replacing DR with SF was prominent in the cows fed fresh TMR.

Oxidation resistance 1 is essential for protection against oxidative stress and participates in the regulation of aging in Caenorhabditis elegans

Human oxidation resistance 1 (OXR1) functions in protection against oxidative damage and its homologs are highly conserved in eukaryotes examined so far, but its function still remains uncertain. In this study, we identified a homolog (LMD-3) of human OXR1 in the nematode Caenorhabditis elegans (C. elegans). The expressed LMD-3 was able to suppress the mutator phenotypes of E. coli mutMmutY and mutT mutants. Purified LMD-3 did not have enzymatic activity against 8-oxoG, superoxide dismutase (SOD), or catalase activities. Interestingly, the expression of LMD-3 was able to suppress the methyl viologen or menadione sodium bisulfite-induced expression of soxS and sodA genes in E. coli. The sensitivity of the C. elegans lmd-3 mutant to oxidative and heat stress was markedly higher than that of the wild-type strain N2. These results suggest that LMD-3 protects cells against oxidative stress. Furthermore, we found that the lifespan of the C. elegans lmd-3 mutant was significantly reduced compared with that of the N2, which was resulted from the acceleration of aging. We further examined the effects of deletions in other oxidative defense genes on the properties of the lmd-3 mutant. The deletion of sod-2 and sod-3, which are mitochondrial SODs, extended the lifespan of the lmd-3 mutant. These results indicate that, in cooperation with mitochondrial SODs, LMD-3 contributes to the protection against oxidative stress and aging in C. elegans.

A phospholipase C-γ1-independent, RasGRP1-ERK-dependent pathway drives lymphoproliferative disease in linker for activation of T cells-Y136F mutant mice

Mice expressing a germline mutation in the phospholipase C-γ1-binding site of linker for activation of T cells (LAT) show progressive lymphoproliferation and ultimately die at 4-6 mo age. The hyperactivated T cells in these mice show defective TCR-induced calcium flux but enhanced Ras/ERK activation, which is critical for disease progression. Despite the loss of LAT-dependent phospholipase C-γ1 binding and activation, genetic analysis revealed RasGRP1, and not Sos1 or Sos2, to be the major Ras guanine exchange factor responsible for ERK activation and the lymphoproliferative phenotype in these mice. Analysis of isolated CD4(+) T cells from LAT-Y136F mice showed altered proximal TCR-dependent kinase signaling, which activated a Zap70- and LAT-independent pathway. Moreover, LAT-Y136F T cells showed ERK activation that was dependent on Lck and/or Fyn, protein kinase C-θ, and RasGRP1. These data demonstrate a novel route to Ras activation in vivo in a pathological setting.

Therapeutic effect of bortezomib for primary plasma cell leukemia followed by auto/allo stem cell transplantation

Plasma cell leukemia (PCL) is a rare disease that represents approximately 4% of plasma cell malignant disorders. PCL consists of two variants: primary PCL presents in patients with no previous history of multiple myeloma, while secondary PCL consists of a leukemic transformation in a previously recognized multiple myeloma. Primary PCL is an extremely resistant, rapidly progressive, fatal disease, with a median overall survival of 6.8 months. There is no standard therapeutic strategy, because no treatment option has been prospectively evaluated. We describe a successful case of newly diagnosed primary PCL, treated with a regimen that included bortezomib, followed by auto stem cell transplantation and nonmyeloablative allogeneic stem cell transplantation. Our patient has maintained remission status for over 12 months since undergoing the allogeneic stem cell transplantation. This strategy is promising for PCL, which, though an extremely resistant disease, may become curable.

Detection of Paracoccidioides brasiliensis gp43 gene in sputa by loop-mediated isothermal amplification method

The fungus Paracoccidioides brasiliensis is the pathogen of paracoccidioidomycosis (PCM), a systemic mycosis prevalent in Latin America. The loop-mediated isothermal amplification method (LAMP) was used in this study to detect the presence of P. brasiliensis in sputa samples from patients with chronic PCM, suspected PCM, and a negative control. The target P. brasiliensis gp43 gene was amplified in less than 4 hr in 11 of 18 sputa samples tested. The LAMP method had the advantage of speed and simplicity compared with the classic diagnostic methods such as the histopathological test or biological material culture and did not require sophisticated technical apparatus. It would be an important aid in cases where immediate treatment would mean patient survival, especially in immune-suppressed patients.

Bam32: a novel mediator of Erk activation in T cells

Bam32 (B lymphocyte adapter molecule of 32 kDa) is an adapter protein expressed in some hematopoietic cells including B and T lymphocytes. It was previously shown that Bam32-deficient mice have defects in various aspects of B cell activation including B cell receptor (BCR)-induced Erk activation, BCR-induced proliferation and T-independent antibody responses. In this study, we have examined the role of Bam32 in T cell activation using Bam32-deficient mice. By comparing CD4(+) T cells from lymph nodes of wild-type and Bam32-deficient mice, we found that Bam32 was required for optimal TCR-induced Erk activation, cytokine production, proliferation and actin-mediated spreading of CD4(+) T cells. These results indicate a novel pathway to Erk activation in T cells involving the adapter protein Bam32.

Continuous remission in an infant with chest wall malignant rhabdoid tumor after relapse

Malignant rhabdoid tumor (MRT) is a highly aggressive tumor that occurs in infancy or childhood. The prognosis, especially in infants, is very poor. Here we report the long-term survival of a 5-month-old boy with MRT that arose from the chest wall. After total resection of the tumor, the patient was given 4 cycles of doxorubicin, vincristine, and cyclophosphamide, alternating with ifosfamide and etoposide. After 18 months off therapy, he had a local recurrence at the same site. After a second total resection, he was given additional chemotherapy with 30.6-Gy local irradiation. No further recurrence has been observed for 5 years since the second complete remission. Currently, he is alive and well at 7.5 years post-onset. Our experience in this case suggests a fundamental strategy of successful treatment of this highly malignant pediatric tumor: (1) complete resection of the localized tumor, (2) intensive multiagent chemotherapy for the minimal disseminated disease, and (3) radiotherapy for local control of the disease.

Matrix metalloproteinase-1 produced by human CXCL12-stimulated natural killer cells

Natural killer (NK) cells play a key role in inflammation and tumor regression through their ability to migrate into tissues. CXCL12 is a chemokine that promotes lymphocyte invasion and migration into tissues; however, the mechanism for this process remains incompletely understood. In this study, we show that CXCL12 significantly enhanced CD16(+)CD56(+) human peripheral NK-cell invasion into type I collagen by the catalytic activity of matrix metalloproteinase-1 (MMP-1). Confocal immunofluorescence and co-immunoprecipitation studies suggest that MMP-1 colocalized with alpha(2)beta(1) integrin on CXCL-12-stimulated NK-cell surface. The binding of pro-MMP-1 with alpha(2)beta(1) integrin required activation of G(i)-coupled pathway. However, the production of MMP-1 from CXCL12-stimulated NK cells was mediated by p38 and mitogen-activated or extracellular signal-regulation protein kinase kinase 1/2 in a manner independent of the G(i)-coupled pathway. These results suggest that CXCL12/CXCR4 interaction transduces the two signaling pathways to promote NK-cell invasion, which stimulates pericellular degradation of extracellular matrix proteins by membrane-associated MMP-1. The mechanisms would thus play a role in facilitating lymphocyte trafficking and accumulation in tissues during physiological and pathological processes.

Investigation of the possible association between nosocomial candiduria and candidaemia

This study aimed to determine whether candiduria is associated with the occurrence of nosocomial candidaemia. In the case-control part of the study, 115 cases (nosocomial candidaemia) and 115 controls (nosocomial bacteraemia) were similar in age, severity of condition and time of hospitalisation. There was a significant association of candidaemia with candiduria (OR 9.79; 95% CI 2.14-44.76). In the microbiology part of the study, 23 pairs of Candida-positive urine and blood cultures were obtained from 23 patients. In ten (43%) cases, the urine and blood culture isolates belonged to different species, and molecular typing showed a difference in two of the 13 cases yielding the same species from both specimens. Overall, there was a significant association between candiduria and candidaemia, but the Candida isolates from urine and blood were different for 52% of the patients. Thus, the data indicated that the urinary tract was probably not a source for the candidaemia.

Antigenuria and antigenaemia in experimental murine paracoccidioidomycosis

In this study, Swiss mice were experimentally infected with Paracoccidoides brasiliensis (Pb18) and we investigated the levels of gp43 in urine and plasma, anti-gp43 and IgG-gp43 immune complexes in plasma. These levels were correlated with the histopathological findings. Blood and urine samples were collected from mice at 7, 28, 56 and 84 days after intravenous inoculation of 10(5) yeast cells, and analysed by ELISA. The results showed increased levels of soluble gp43 in the plasma in all periods, and anti-gp43 IgG and immune complexes after day 28. High gp43 levels were detected in the urine, except for day 28, coincident with the presence of compact granulomas in lungs. All the infected mice showed fungal cells in the lungs, with initial granulomatous lesions at day 7, dissemination of lesions to other organs at day 56, and granulomas lacking the surrounding mononuclear cells infiltration, especially at days 56 and 84. Our results suggest that gp43 diffuses passively into the urine, and the determination of gp43 levels in urine samples may be a non-invasive alternative method for diagnosis and follow up of PCM. Further studies are needed to determine if the cellular immune response correlate with decreased urine gp43 levels.

Evaluation of Fusarium solani hyphae and conidia susceptibility to amphotericin B and itraconazole: study of a clinical case

Fusarium species are hyaline moulds belonging to the hyalohyphomycosis group that are usually found in the soil and plants. This organism has emerged as a cause of disseminated invasive disease. The correlation between in vitro value and clinical efficacy is low and many patients remain unresponsive to treatment despite in vitro susceptibility. We determined growth control for Fusarium solani using the BioCell-Tracer system that measures the growth rate of a single fungal hypha, and the effect of different concentrations of amphotericin B and itraconazole. The MIC for these two drugs was also determined by a broth microdilution technique, using RPMI 1640. Different MICs for amphotericin B were obtained by the two different methods. This paper describes a case of infection due to Fusarium solani in an allogeneic bone marrow transplanted patient, the microbiological diagnostic, antifungal susceptibility tests for conidia and hypha and clinical correlation.

Diagnosis of candidemia by polymerase chain reaction and blood culture: prospective study in a high-risk population and identification of variables associated with development of candidemia

The diagnosis of candidemia is important for prompt initiation of antifungal therapy. Two hundred twenty-five patients at high risk for candidemia who had blood cultures drawn and were hospitalized for more than 15 days were followed-up prospectively over a 2-year period. Polymerase chain reaction (PCR) and whole-blood cultures monitored by the automated BactAlert system (Organon Teknika, Durham, NC, USA) were used to detect candidemia in all patients hospitalized in high-risk areas for more than 15 days. DNA was extracted and amplified using ITS5 and ITS4 base pair primers, and the PCR products were sequenced for identification of Candida spp. A blood culture positive for Candida was considered the gold standard for diagnosis of candidemia. Variables associated with the development of candidemia diagnosed by positive blood culture were also evaluated in the patients. The overall mortality rate was 26.1%. Mortality in candidemic patients was 41.9% and in noncandidemic patients 22.5% (p = 0.009). PCR sensitivity and specificity were 72.1 and 91.2%, respectively. Positive and negative predictive values were 65.9 and 93.2%, respectively. The logistic regression of the multivariate analysis showed that parenteral nutrition (p < 0.0001), fever (p = 0.01), neutropenia (p = 0.04), and an indwelling urinary catheter (p = 0.02) were significant variables associated with the development of candidemia. The PCR technique in conjunction with DNA sequencing was a helpful tool in the diagnosis of candidemia.

Antifungal Susceptibility and Pathogenic Potential of Environmental Isolated Filamentous Fungi Compared with Colonizing Agents in Immunocompromised Patients

Infection is a major cause of morbidity and mortality in bone marrow transplant recipients and in patients with hematological malignancies. The source of infection is almost always endogenous flora or the hospital environment. The present study evaluated bone marrow transplant recipients and patients with hematological malignancies colonized and/or infected with filamentous fungi. During 1 year, environmental air samples were also taken from the bone marrow transplant unit by a modification of gravity air-setting plate (GASP) methodology. Fusarium spp. were the most prevalent genus in the fall and Cladosporium spp. in the winter. Clinically isolated strains grew better at 37 degrees C than environmental strains. According to NCCLS M-38P methods, environmental Aspergillus strains showed higher MICs to miconazol and itraconazol, and clinical Fusarium strains were less susceptible to fluconazole.

IL-4-producing CD8+ T cells may be an immunological hallmark of chronic GVHD

Chronic graft-versus-host disease (cGVHD) occurs in approximately 60-80% of those who survive over 100 days after allogeneic hematopoietic stem cell transplantation (allo-HSCT). However, the pathophysiology of cGVHD is poorly understood. To gain more insight into the immunological mechanism of cGVHD, we examine cytokine production of peripheral blood T cells from 19 patients in the chronic phase of allo-HSCT. The percentage of IFN-gamma-producing CD8(+) T cells among CD8(+) T cells was significantly higher in patients with or without cGVHD than in normal control subjects (P<0.001). On the other hand, the percentage of IL-4-producing CD8(+) T cells among CD8(+) T cells was significantly higher in patients with cGVHD (mean 3.3%; range 1.3-8.2%) than in patients without cGVHD (mean 1.2%; range 0.8-1.7%) and normal control subjects (mean 1.1%; range 0.1-1.6%) (both P<0.001). By contrast, the percentage of IL-4-producing CD4(+) T cells was not different among patients with and without cGVHD and normal controls. These findings suggest that IL-4-producing CD8(+) T cells may be an immunological marker of cGVHD.

Role of membrane sphingomyelin and ceramide in platform formation for Fas-mediated apoptosis

Engagement of the Fas receptor (CD95) initiates multiple signaling pathways that lead to apoptosis, such as the formation of death-inducing signaling complex (DISC), activation of caspase cascades, and the generation of the lipid messenger, ceramide. Sphingomyelin (SM) is a major component of lipid rafts, which are specialized structures that enhance the efficiency of membrane receptor signaling and are a main source of ceramide. However, the functions of SM in Fas-mediated apoptosis have yet to be clearly defined, as the responsible genes have not been identified. After cloning a gene responsible for SM synthesis, SMS1, we established SM synthase–defective WR19L cells transfected with the human Fas gene (WR/Fas-SM(−)), and cells that have been functionally restored by transfection with SMS1 (WR/Fas-SMS1). We show that expression of membrane SM enhances Fas-mediated apoptosis through increasing DISC formation, activation of caspases, efficient translocation of Fas into lipid rafts, and subsequent Fas clustering. Furthermore, WR/Fas-SMS1 cells, but not WR/Fas-SM(−) cells, showed a considerable increase in ceramide generation within lipid rafts upon Fas stimulation. These data suggest that a membrane SM is important for Fas clustering through aggregation of lipid rafts, leading to Fas-mediated apoptosis.

Interleukin-2-induced survival of natural killer (NK) cells involving phosphatidylinositol-3 kinase-dependent reduction of ceramide through acid sphingomyelinase, sphingomyelin synthase, and glucosylceramide synthase

Interleukin 2 (IL-2) rescued human natural killer (NK) KHYG-1 cells from apoptosis along with a reduction of ceramide. Conversely, an increase of ceramide inhibited IL-2-rescued survival. IL-2 deprivation-induced activation of acid sphingomyelinase (SMase) and inhibition of glucosylceramide synthase (GCS) and sphingomyelin synthase (SMS) were normalized by IL-2 supplementation. A phosphatidyl inositol-3 (PI-3) kinase inhibitor, LY294002, inhibited IL-2-rescued survival, but a mitogen-activated protein kinase inhibitor, PD98059, and an inhibitor of Janus tyrosine kinase/signal transducer and activator of transcription pathway, AG490, did not. LY294002 inhibited IL-2-induced reduction of ceramide through activation of acid SMase and inhibition of GCS and SMS, suggesting the positive involvement of PI-3 kinase in ceramide reduction through enzymatic regulation. Indeed, a constitutively active PI-3 kinase enhanced growth rate and ceramide reduction through inhibition of acid SMase and activation of GCS and SMS. Further, LY294002 inhibited IL-2-induced changes of transcriptional level as well as mRNA and protein levels in acid SMase and GCS but did not affect the stability of the mRNAs. These results suggest that PI-3 kinase-dependent reduction of ceramide through regulation of acid SMase, GCS, and SMS plays a role in IL-2-rescued survival of NK cells. (Blood. 2004;104:3285-3293)

Oral Candida flora from Brazilian human immunodeficiency virus-infected patients in the highly active antiretroviral therapy era

One of the main opportunistic fungal infections amongst immunocompromised individuals is oral candidosis, which has been found in up to 90% of human immunodeficiency virus (HIV)-infected patients. This study employed yeasts isolated from the saliva and oral cavities of 114 HIV-infected patients living in Campinas, São Paulo. Of the isolates, 57.8% were identified as Candida albicans and 42.1% as non-C. albicans. The latter isolates were subsequently identified as C. krusei (7.5%), C. lusitaniae (5.2%), C. tropicalis (4.6%), C. parapsilosis (4.6%), C. glabrata (2.8%), C. kefyr (1.7%), C. guilliermondii (1.7%), C. intermedia (1.1%), C. norvegensis (0.5%), and Rhodotorula rubra (1.7%). Susceptibility of the isolates to amphotericin B, fluconazole, miconazole, and itraconazole was also determined by a microdilution method adopted by the National Committee for Clinical Laboratory Standards. The isolates demonstrated various susceptibilities to the antifungal agents. In particular 29 C. albicans and 13 non-C. albicans isolates showed low susceptibility to FLCZ (> 64 micro g/ml). This study revealed huge diversity of Candida species, in particular the increasing emergence of non-C. albicans associated with the oral flora of HIV-infected patients.

Blood dendritic cells are decreased in acute graft-versus-host disease

The recipients of allogeneic hematopoietic stem cell transplantation (allo-HSCT) often develop acute graft-versus-host disease (aGVHD), which is closely related to morbidity and mortality. However, the essential part of the immune responses elicited in aGVHD remains largely unknown. We attempt to determine if peripheral blood dendritic cells (PBDCs) are altered in aGVHD, and find that the number of PBDCs (both myeloid and lymphoid DCs) is significantly decreased. Immunohistochemical staining of the biopsied skin from patients with aGVHD demonstrates that a number of fascin(+) cells with dendritic projections infiltrate the dermis of the skin. Based on these findings, we hypothesize that the PBDCs are recruited to the affected tissues and may thus play important roles in immune responses elicited in aGVHD.

Expression Cloning of a Human cDNA Restoring Sphingomyelin Synthesis and Cell Growth in Sphingomyelin Synthase-defective Lymphoid Cells

Sphingomyelin (SM) synthase has been assumed to be involved in both cell death and survival by regulating pro-apoptotic mediator ceramide and pro-survival mediator diacylglycerol. However, its precise functions are ambiguous due to the lack of molecular cloning of SM synthase gene(s). We isolated WR19L/Fas-SM(-) mouse lymphoid cells, which show a defect of SM at the plasma membrane due to the lack of SM synthase activity and resistance to cell death induced by an SM-directed cytolytic protein lysenin. WR19L/Fas-SM(-) cells were also highly susceptible to methyl-beta-cyclodextrin (MbetaCD) as compared with the WR19L/Fas-SM(+) cells, which are capable of SM synthesis. By expression cloning method using WR19L/Fas-SM(-) cells and MbetaCD-based selection, we have succeeded in cloning of a human cDNA responsible for SM synthase activity. The cDNA encodes a peptide of 413 amino acids named SMS1 (putative molecular mass, 48.6 kDa), which contains a sterile alpha motif domain near the N-terminal region and four predicted transmembrane domains. WR19L/Fas-SM(-) cells expressing SMS1 cDNA (WR19L/Fas-SMS1) restored the resistance against MbetaCD, the accumulation of SM at the plasma membrane, and SM synthesis by transferring phosphocholine from phosphatidylcholine to ceramide. Furthermore, WR19L/Fas-SMS1 cells, as well as WR19L/Fas-SM(-) cells supplemented with exogenous SM, restored cell growth ability in serum-free conditions, where the growth of WR19L/Fas-SM(-) cells was severely inhibited. The results suggest that SMS1 is responsible for SM synthase activity in mammalian cells and plays a critical role in cell growth of mouse lymphoid cells.

Plasmacytoid Dendritic Cells Regulate Th Cell Responses through OX40 Ligand and Type I IFNs

Dendritic cells (DCs) show a functional plasticity in determining Th responses depending on their maturational stage or on maturational signals delivered to the DCs. Human plasmacytoid DCs (PDCs) can induce either Th1- or Th2-type immune responses upon exposure to viruses or IL-3, respectively. In this study we have investigated the Th-polarizing capacity of PDCs after short (24-h) or long (72-h) culture with stimuli and have assessed the expression and function of OX40 ligand (OX40L) in PDC-mediated Th polarization in addition to type I IFN-dependent responses. IL-3-treated PDCs expressed OX40L, but produced almost no IFN-alpha in response to T cell stimulation (CD40 ligand or T cell interaction), resulting in the preferential priming of Th2 cells through OX40L-dependent mechanisms. Meanwhile, PDCs were rapidly endowed by viral infection (Sendai virus) with a high potency to develop IFN-gamma-producing Th cells depending on their capacity to residually produce IFN-alpha. Although Sendai virus-stimulated PDCs simultaneously expressed OX40L in their maturational process, the Th1-inducing effect of endogenous type I IFNs may overcome and thus conceal the OX40L-dependent Th2 responses. However, during maturation in response to Sendai virus over the longer 72-h period, the expression level of OX40L was up-regulated, whereas the residual IFN-alpha-producing ability was down-regulated, and consequently, the PDCs with prolonged Sendai virus stimulation induced Th2 responses to some extent. Thus, PDCs have the distinct means to dictate an appropriate response to environmental stimuli.

Synergistic antifungal effect of fluconazole and human polymorphonuclear leukocytes on Paracoccidioides brasiliensis: effect of interferon-gamma and granulocyte-macrophage colony-stimulating factor

To better understand the in vivo efficacy of fluconazole (FCZ), we investigated the possible synergy of fungistatic FCZ with human polymorphonuclear leukocytes (PMN) against Paracoccidioides brasiliensis (Pb). The effect of interferon-gamma (IFN-gamma) and granulocyte-macrophage colony-stimulating factor (GM-CSF) in this system was also studied. For this purpose, FCZ, PMN, PMN + FCZ, PMN + IFN-gamma, PMN + IFN-gamma + FCZ, PMN + GM-CSF and PMN + GM-CSF + FCZ were co-cultured with Pb and the cfu of Pb was measured. The antifungal effect of FCZ on yeast cells of Pb was concentration-dependent. At 0.1 microg ml(-1), FCZ had no effect on the growth of Pb. At 0.2 microg ml(-1) FCZ showed a growth-inhibitory effect on three isolates of Pb in a long-term (120 h) assay, and at 0.6 microg ml(-1) or higher FCZ was fungicidal. Fungistatic concentration of FCZ (0.4 microg ml(-1)) acted synergistically with fungistatic PMN for killing isolate Bt-4 during the first 24 h of co-culture. Moreover, IFN-gamma and GM-CSF substantially enhanced the synergistic antifungal effect of PMN and FCZ. These findings provide a better understanding of why FCZ is more efficacious in in vivo models of paracoccidioidomycosis than is predicted by in vitro susceptibility tests.

Immunomodulatory effects of cyclosporin A on human peripheral blood dendritic cell subsets

Cyclosporin A (CsA) is a potent immuno-suppressant and is approved for the treatment of various disease conditions. The molecular biological mechanism of CsA has been investigated intensively in T cells and has been shown to involve the intracellular calcineurin pathway. Recently, it was reported that CsA has capacities to affect not only T cells but also antigen-presenting cells such as B cells and dendritic cells (DCs). DCs are a master regulator of immune responses that have an integral capacity to prime naive T cells. In the present study, we investigated the biological effects of CsA on human peripheral blood DC subsets: CD11c+ myeloid and CD11c- lymphoid subsets. CsA inhibited the up-regulation of co-stimulatory molecules induced with or without microbial stimuli and CD40L on both CD11c+ and CD11c- subsets. In addition, CsA negatively regulated the endocytic activity of CD11c+ DC during the immature state. CsA inhibited the interleukin-12 (IL-12) production, but augmented the IL-10 production from the LPS-stimulated CD11c+ subset, whereas CsA reduced the interferon-alpha (IFN-alpha) production from the CD11c- subset infected with Sendai virus (SV). Both the LPS-stimulated CD11c+ subset and SV-infected CD11c- subset preferentially induced the development of IFN-gamma-producing T helper-type 1 (Th1) cells. Pretreatment of these DC subsets with CsA inhibited the Th1 skewing. These findings suggested a DC-mediated mechanism of immunosuppression by CsA.

Membrane-bound form of fractalkine induces IFN-gamma production by NK cells

Natural killer (NK) cells participate in both innate and adaptive immunity, in part by their prompt secretion of cytokines including IFN-gamma, a pro-inflammatory cytokine with an important role in Th1 polarization. To assess the involvement of fractalkine in inflammatory processes, we examined the effect of fractalkine on IFN-gamma production by NK cells. Although soluble chemokines, including MCP-1 and RANTES as well as fractalkine, had a negligible effect on IFN-gamma production, immobilized fractalkine markedly induced IFN-gamma production by NK cells in a dose-dependent manner. Pretreatment of NK cells with the phosphatidylinositol 3-kinase (PI 3-K) inhibitor, wortmannin, completely inhibited the production of IFN-gamma induced by fractalkine, and pretreatment with the protein tyrosine kinase inhibitor, herbimycin A, partially suppressed the response, suggesting that augmentation of IFN-gamma production in response to fractalkine treatment of NK cells involves signaling through PI 3-K and protein tyrosine kinases. Furthermore, co-culture of NK cells with fractalkine-transfected 293E cells markedly enhanced IFN-gamma production by NK cells compared with co-culture with control 293E cells. These findings may indicate a paracrine feedback loop system in which endothelial cells may be activated to produce more fractalkine, and also suggest a role for fractalkine expressed on endothelial cells in Th1 polarization through the stimulation of IFN-gamma production by NK cells.

Phaeohyphomycosis Caused byChaetomium Globosumin an Allogeneic Bone Marrow Transplant Recipient

Bone marrow transplant recipients are highly susceptible to opportunistic fungal infections. This is the report, of the first case of a Chaetomium systemic infection described in Brazil. A 34 year-old patient with chronic myeloid leukemia underwent an allogeneic sibling matched bone marrow transplant. Seven months later, he developed systemic infection with enlargement of the axillary and cervical lymph nodes. Culture of the aspirates from both lymph nodes yielded Chaetomium globosum. The infection was successfully treated with amphotericin B. The increasing population of immunosupressed patients requires a careful microbiologic investigation for uncommon fungal infections.

Lipid rafts as the signaling scaffold for NK cell activation: tyrosine phosphorylation and association of LAT with phosphatidylinositol 3-kinase and phospholipase C-gamma following CD2 stimulation

Natural killer (NK) cells participate in both innate and adaptive immunity through the prompt secretion of cytokines and ability to lyse virally infected cells or tumor cells. Although it has been well understood that lipid rafts (rafts) and a raft-associated linker for activation of T cells (LAT) plays a central role in TCR signal transduction, there are still great gaps in our knowledge of the molecular events involved in NK cell activation. We show here that CD2 and rafts became polarized to the site of NK cell activation by CD2 cross-linking or target cell binding using confocal microscopy, and LAT and a significant amount of CD2 colocalized in raft fractions of sucrose-density gradient from an NK cell line, NK3.3. CD2 cross-linking strongly induced tyrosine phosphorylation of LAT, resulting in increased association with phosphatidylinositol 3-kinase (PI 3-K) and phospholipase C-gamma1 (PLC-gamma1). In vitro binding studies using glutathione S-transferase fusion proteins demonstrated that a large portion of the association between LAT and PI 3-K or PLC-gamma1 was mediated through their SH2 domains in tyrosine phosphorylation-dependent manner. Furthermore, disruption of lipid rafts by cholesterol depletion from cell membranes using methyl-beta-cyclodextrin markedly reduced LAT tyrosine phosphorylation and NK cell functions, including cytotoxicity and granule exocytosis. These results document that modulation of raft integrity by aggregation of NK cell activating receptors, which leads to the formation of complexes of LAT with PI 3-K and PLC-gamma1, is essential for the NK cell lytic mechanisms.

Pathogenicity and virulence of Candida dubliniensis: comparison with C. albicans

Candida dubliniensis is a newly described fungus that is frequently isolated from the oral cavities of HIV-positive patients. Although extensive studies have been performed on the phylogeny of C. dubliniensis, little is known about the pathogenic ecology of this yeast. Here we examined aspects related to C. dubliniensis in comparison with those of C. albicans. When injected intravenously into mice, C. dubliniensis had a higher survival rate than C. albicans. Histopathological analysis disclosed that C. dubliniensis remained mostly in the yeast form in the infected organs, whereas C. albicans changed into the mycelial form. The host inflammatory reaction was aggressive with C. dubliniensis infection and mild with C. albicans infection. Co-culture of the yeasts with human polymorphonuclear leukocytes disclosed that C. dubliniensis is more vulnerable to the fungicidal activity of leukocytes than C. albicans. C. dubliniensis was also more susceptible to the toxic effect of hydrogen peroxide. When cultured in vitro, C. dubliniensis grew more slowly than C. albicans, but the formation of germ tubes was faster. When the fungi were cultured in RPMI 1640, a fetal bovine serum supplement suppressed the growth of C. dubliniensis but enhanced that of C. albicans. These results clearly indicated that C. dubliniensis is less virulence than C. albicans.

In vitro activity of FK463, a novel lipopeptide antifungal agent, against a variety of clinically important molds

The in vitro antifungal activity of FK463 against a variety of clinically important opportunistic molds was compared with amphotericin B, itraconazole and fluconazole by using the broth microdilution method M27-A specified by the National Committee for Clinical Laboratory Standards. FK463 exhibited potent activity against Aspergillus species, which was superior to those of all other compounds tested. FK463 was also active against the dematiaceous fungi Cladosporium trichoides, Exophiala spinifera, Fonsecaea pedrosoi, and Exophiala dermatitidis except for certain clinical isolates. However, FK463 had no activity against Fusarium solani, Pseudallesheria boydii, and the zygomycetes Absidia corymbifera, Cunninghamella elegans, Rhizopus oryzae, and Rhizopus microsporus var. rhizopodiformis. These results suggest that FK463 has potential utility for the treatment for infections caused by Aspergillus species and dematiaceous fungi.

[Two cases of canine histoplasmosis in Japan]

Histoplasmosis is distributed in tropical, subtropical and temperate zones of the world. The disease is one of the imported mycoses in Japan. To date, although more than 30 human and one canine case of histoplasmosis have been reported in Japan, some including that of the canine might have been infected domestically, since the patients have no history of going abroad. The pathogen of histoplasmosis is thus believed to be present in our country. We examined skin biopsies from two dogs in Tokyo and Kumamoto, and found fungal elements 1-2 or 2-4 microEm in diameter in the macrophages. The homology of DNA sequences for the ITS rRNA gene were correspondent to Ajellomyces capsulatus at a rate of more than 97.4%. Therefore, the two dogs were diagnosed as having been infected with Histoplasma capsulatum which is the anamorph of A. capsulatus. Since the dogs had no history of having been outside Japan and had not been brought from an endemic area, they might have been infected domestically. Further epidemiological surveys on canine histoplasmosis may be able to estimate autochthonous human cases in Japan.

Identification of species in Aspergillus section Flavi based on sequencing of the mitochondrial cytochrome b gene

The partial sequences of the mitochondrial (mt) cytochrome b gene (402 bp) were determined for species of Aspergillus section Flavi. On the basis of identities of DNA sequences, 77 strains were divided into seven DNA types, from D-1 to D-7. The type strains of A. sojae, A. parasiticus, A. flavus and A. oryzae together, A. tamarii, and A. nomius were placed in DNA types D-1. D-2, D-4, D-5 and D-7, respectively. These species could be differentiated from each other. Furthermore, two other DNA types, D-3 and D-6 were found. DNA type D-3 was closely related to A. parasiticus (D-2) and included one strain that deposited as A. flatus var. flavus and produced aflatoxins B and G. DNA types D-6 included one strain named A. flavus and closely related to A. tamarii. The observations of conidial wall texture by SEM (Scanning Electron Microscopy) supported the relationships derived from the cytochrome b gene. The production of aflatoxins was also examined. Using the DNA sequence of cytochrome b gene, several strains were reidentified. The derived amino acids sequences were all the same in the studied strains. The mt cytochrome b gene is useful and reliable in distinguishing and identifying the species in Aspergillus section Flavi.

Identification, classification, and phylogeny of the pathogenic species Exophiala jeanselmei and related species by mitochondrial cytochrome b gene analysis

We analyzed a 402-bp sequence of the mitochondrial cytochrome b gene of 34 strains of Exophiala jeanselmei and 16 strains representing 12 related species. The strains of E. jeanselmei were classified into 20 DNA types and 17 amino acid types. The differences between these strains were found in 1 to 60 nucleotides and 1 to 17 amino acids. On the basis of the identities and similarities of nucleotide and amino acid sequences, some strains were reidentified: i.e., two strains of E. jeanselmei var. hetermorpha and one strain of E. castellanii as E. dermatitidis (including the type strain), three strains of E. jeanselmei as E. jeanselmei var. lecanii-corni (including the type strain), three strains of E. jeanselmei as E. bergeri (including the type strain), seven strains of E. jeanselmei as E. pisciphila (including the type strain), seven strains of E. jeanselmei as E. jeanselmei var. jeanselmei (including the type strain), one strain of E. jeanselmei as Fonsecaea pedrosoi (including the type strain), and one strain of E. jeanselmei as E. spinifera (including the type strain). Some E. jeanselmei strains showed distinct nucleotide and amino acid sequences. The amino-acid-based UPGMA (unweighted pair group method with the arithmetic mean) tree exhibited nearly the same topology as those of the DNA-based trees obtained by neighbor joining, maximum parsimony, and maximum likelihood methods.

Atypical Cryptococcus neoformans isolate from an HIV-infected patient in Brazil

Cryptococcus neoformans is an important fungal pathogen in immunocompromised hosts. Capsulation, urease and melanin synthesis activity of the fungus are well known virulence factors. Although artificial melanin-deficient mutants of Cr. neoformans have been investigated, the clinical mutant is rare. We found a Cr. neoformans isolate in the cerebrospinal fluid of an AIDS patient which produced a light tan colony on a caffeic acid cornmeal agar (CACA) plate. The mycological feature of the isolate was as follows; normal capsulation, defective inositol assimilation ability, serotype A; urease-positive; mating type alfa; haploid; extremely slow growth in RPMI 1640 medium, Sabouraud dextrose broth, brain heart infusion broth and yeast nitrogen base; lower production of melanin with L-DOPA substrate; and low virulence to ddY mice. We also investigated the partial DNA sequence of CNLAC1 gene between the 3085th to 3623rd base. There were many substitutions, 3 insertions and 3 deletions in the isolate compared with GenBank accession number L22866. The result indicated some functional disorder in the gene. Although the CACA plate is an excellent selective medium for Cr. neoformans, other identification methods should also be used.

Extrusion of fluorescein diacetate by multidrug-resistant Candida albicans

Over-expression of multidrug efflux transporters causes Candida albicans cells to be resistant to azole antifungal agents. There are several kinds of indicator for multidrug resistance (MDR) phenotype of higher eukaryotic cells. Calcein AM is a prefluorochrome that is known as a substrate for multidrug efflux transporters of mammalian cells. We investigated whether calcein AM was also extruded by the ATP-dependent multidrug transporter (cdr1p) of C. albicans. There was no significant difference in the accumulation of calcein AM between MDR cells and drug-susceptible cells of C. albicans even with sodium azide, suggesting that calcein AM may not be associated with the CDR1-gene-related multidrug efflux system of C. albicans. However, a structurally related prefluorochrome derivative, fluorescein diacetate (FDA), was shown to be extruded by the CDR1 mRNA-overexpressing yeast cells. In comparison with drug-susceptible cells, the resistant cells emitted very weak fluorescence when stained with FDA. Furthermore sodium azide increased the fluorescence of the resistant cells more than 20 times, whereas the fluorescence in the drug-susceptible cells with FDA and sodium azide was three to four times stronger. These results suggested that FDA might be extruded by the CDR1-related multidrug efflux transporter of C. albicans.