12–15 In addition to aiding in the early diagnosis and prediction

12–15 In addition to aiding in the early diagnosis and prediction, they should be highly specific for AKI, and enable the identification

of AKI subtypes and aetiologies. AKI is traditionally diagnosed when the kidney’s major function BMS-777607 datasheet (glomerular filtration) is affected, and indirectly measured by change in serum creatinine. However, pre-renal factors such as volume depletion, decreased effective circulating volume or alterations in the calibre of the glomerular afferent arterioles all cause elevations in serum creatinine. Post-renal factors such as urinary tract obstruction similarly result in elevations in serum creatinine. Finally, a multitude of intrinsic renal diseases may result in abrupt rise in serum creatinine, particularly in hospitalized patients. Other tests to distinguish these various forms of AKI such as microscopic urine examination for casts and determination of fractional excretion Everolimus of sodium have

been imprecise and have not enabled efficient clinical trial design. Availability of accurate biomarkers that can distinguish pre-renal and post-renal conditions from true intrinsic AKI would represent a significant advance. Biomarkers may serve several other purposes in AKI.12–15 Thus, biomarkers are also needed for: (i) identifying the primary location of injury (proximal tubule, distal tubule, interstitium or vasculature); (ii) pinpointing the duration of kidney failure

(AKI, chronic kidney disease (CKD) or ‘acute-on-chronic’ kidney injury); (iii) identifying AKI aetiologies (ischaemia, toxins, sepsis or a combination); (iv) risk stratification and prognostication (duration and severity of AKI, need for dialysis, length of hospital stay, mortality); and (v) monitoring the response to AKI interventions. Furthermore, AKI biomarkers may play a critical role in expediting the drug development process. The Critical Path Initiative first issued by the Food and Drug Administration in 2004 stated that ‘Additional biomarkers (quantitative measures of biologic effects that provide informative links between mechanism of Reverse transcriptase action and clinical effectiveness) and additional surrogate markers (quantitative measures that can predict effectiveness) are needed to guide product development’. Collectively, it is envisioned that biomarkers will play an indispensable role in personalizing nephrologic care, by providing a more precise determination of disease predisposition, diagnosis and prognosis, earlier preventive and therapeutic interventions, a more efficient drug development process, and a safer and more fiscally responsive approach to medicine.

Simple back-projection produces a blurred image because it assume

Simple back-projection produces a blurred image because it assumes that the density distribution along the path of each ray is uniform. The density of each pixel of the projected image, however, can be related to those of the pixels in neighboring positions of the adjacent projections. The smaller the difference in the angle between adjacent projections, the greater is the resolution, and the wider the range of angles, the more complete is the three-dimensional PARP inhibitor image. DeRosier and Klug used Fourier transforms to quantify density information of each image [7], but this approach has been superseded by developments in the digitization of images and computation. Initially, the success of electron tomography was largely restricted

to defining the three-dimensional structures of viruses and macromolecules. Its impact on other aspects of biological ultrastructure was limited until the development of dual axis tomography in the 1990s. Here, two stacks of projected images are used, the first being gained by rotating the object through a wide range of angles around learn more one axis (typically 120° in one degree steps), and then through a similar range around a second axis perpendicular to the first. Improvements in computation have meant that electron tomography

is now the method of choice for revealing the three-dimensional structure of objects with recent reports of 0.24 nm resolution [22]. Using electron tomography, Wagner et al. [25] have examined the vesicular system of endothelial cells in thick sections of muscle capillaries. They reveal isolated single vesicles in the cytoplasm and chains of fused vesicles forming channels between the plasma and the interstitial fluid. AMP deaminase These images would have been controversial 20–30 years ago, particularly as they show terbium, which had been in the vascular perfusate, labeling trans-endothelial channels, and so implying a role of the vesicular system as a permeability pathway. From the time of Palade’s first electron micrographs of microvessels [14], it was speculated that the caveolae and small vesicles had

a role in permeability, acting as ferry-boats or shuttles across the endothelium. While such a mechanism could not account for the very rapid exchange of water and low molecular weight solutes between the plasma and the interstitial fluid, it could be responsible for the low but finite permeability of microvascular walls to macromolecules. About the same time as this role for the vesicles was first being discussed, Grotte [10] published his investigations on the passage of dextrans of differing molecular size between the plasma and the lymph. He proposed that large molecules crossed the endothelial barrier through a very small population of pores with radii in the range of 15–20 nm. These became known as the large pores in contrast to Pappenheimer’s small pores with radii of 3–4 nm that were believed to be the pathway for rapid exchanges of fluid and small solute molecules.

It is assumed to exert multiple functions including packaging of

It is assumed to exert multiple functions including packaging of pre-mRNA, regulation of alternative splicing, and nucleo-cytoplasmic transport of mRNA 7. HnRNP-A2 appears to be ubiquitously expressed, although the level of expression may greatly vary between different tissues. Interestingly,

hnRNP-A2 is overexpressed in RA synovial tissue, where it is detectable not only in the nucleus but also in the cytoplasm of macrophages and fibroblast-like synoviocytes 8. Autoantibodies see more to hnRNP-A2 (which are also known as anti-RA33 Ab) are present in approximately 30% of RA patients 9, but also in patients with systemic lupus erythematosus (SLE) and mixed connective tissue disease 9. Remarkably, however, epitope recognition was found to differ between the three disorders 10. Furthermore, also T cells from peripheral blood and synovial fluid of RA patients were found to

react to hnRNP-A2, in about 60% of the patients 8. Interestingly, autoimmunity to hnRNP-A2 has been observed in TNF-transgenic (Tg) mice 11, which develop arthritis spontaneously, and is a dominant immunological event in pristane-induced arthritis in rats 12. Altogether, the results suggest that this protein is an important and potentially pathogenic autoantigen in animal models of arthritis and in RA. Thus, it was the aim of the present study to characterize putative pathogenic T-cell epitopes of hnRNP-A2. To achieve this goal, we started with a comprehensive investigation of MHC binders among a library Wnt inhibition aminophylline of 15-mer peptides spanning the entire human hnRNP-A2 protein. Peptides of this length can bind directly to MHC class II molecules on the cell surface

of APC where they can stimulate peptide-specific T cells. This method allows the analysis of all possible determinants regardless of whether the peptide is dominant or cryptic following natural processing. Then, to identify hnRNP-A2-specific T-cell epitopes in patients with RA, we used a sensitive IFN-γ ELISPOT assay, which detects in vivo-generated antigen-specific T cells in a low frequency range 13. The data obtained were confirmed in proliferation assays and reveal the presence of an immunodominant T-cell epitope associated to active RA. We synthesized 280 15-mer peptides overlapping by 13 or 14 amino acids and spanning the whole hnRNP-A2 sequence. These peptides were tested by competitive ELISA for binding to the RA-associated DR*0101 and DR*0401 molecules. The results obtained show that most epitopes binding to either DR*0101 or DR*0401 were localized in the N-terminal half (first 170 amino acids) of the hnRNP-A2 sequence (Fig. 1). Presence of an MHC epitope was revealed by 4–7 consecutive binding peptides. Frequently, many more consecutive peptides were binding, indicating overlapping epitopes. Six major determinants were found to bind to both DR*0101 and DR*0401: peptides no.

Generally, spleen cells were obtained at the time of

BALF

Generally, spleen cells were obtained at the time of

BALF collection from experimental HP mice. CD4+ T-cell purification and staining with PKH67 were performed according to the manufacturer’s protocol (Sigma). Pre-stained CD4+ T cells were diluted (BALF cells: T cells) 1:6 or 1:12, then co-cultured for 3 days. A T-cell proliferation index was evaluated by measuring the decreasing PKH67 staining intensities in CD4+ T cells after co-culture with BALF cells. For in vitro experiments, the effects of CD11b+Ly-6Chigh or CD11b+Ly-6C− cells on T-cell proliferation were assessed using [3H] thymidine as described previously 11. In brief, U-bottom 96-well plates were coated with anti-CD3/CD28 antibodies (1 μg/mL each) EPZ 6438 overnight at 4°C. CD4+ T cells (0.3×105 cells/well) were

purified using specific MACS beads (Miltenyi Biotec) and then cultured with plate-bound anti-CD3/CD28 for 3 days. The activated CD4+ T cells were co-cultured with BM cell-derived CD11b+Ly-6Chigh, CD11b+Ly-6Cint, and CD11b+Ly-6C− cells from the beginning of the culture. During the final 16 h of the 3-day culture, 1 μCi [3H] thymidine was added, and the check details cells were then harvested. The supernatants (50 μL) were harvested before addition of [3H] thymidine to measure cytokine levels. For statistical comparisons, non-parametric two-tailed Mann–Whitney U-tests and two-way ANOVA were used. All statistical analyses were performed with Prism 4 software (GraphPad Software, La Jolla, CA, USA). We thank Ms. Masako Seki, Ms. Kanako Ito, Ms. Megumi Nagayama and Mr. Tetsuya Shiota (GalPharma, Japan) for technical nearly assistances and Dr. Aya Yokota (Faculty of Pharmaceutical Sciences at Kagawa Campus, Tokushima Bunri University, Japan) for technical assistance with cell sorting. This work was supported, in part, by a Grant-In-Aid for young scientists (B) 2008-2009 (20790570) to T. A. from the Japan Society for Promotion of Science (JSPS), by Kagawa University Characteristic Prior Research Fund 2009 to M. H., and by grants from the Japanese Ministry of Education, Culture, Sports, Science, and Technology.

Conflict of interest: The authors declare no financial or commercial conflict of interest. “
“Invariant NKT (iNKT)-cell stimulation with exogenous specific ligands prevents the development of type 1 diabetes (T1D) in NOD mice. Studies based on anti-islet T-cell transfer showed that iNKT cells prevent the differentiation of these T cells into effector T cells in the pancreatic lymph nodes (PLNs). We hypothesize that this defective priming could be explained by the ability of iNKT cells to induce tolerogenic dendritic cells (DCs) in the PLNs. We evaluated the effect of iNKT-cell stimulation on T1D development by transferring naïve diabetogenic BDC2.5 T cells into proinsulin 2−/− NOD mice treated with a long-lasting α-galactosylceramide regimen.

While there is a clear role for MyD88 in the ability of conventio

While there is a clear role for MyD88 in the ability of conventional mice to mount neutrophilic inflammation to zymosan, we found that several other innate immune signalling pathways were not required for this response. Although Clarke et al. have reported that commensal bacteria prime neutrophils via NOD1 signalling in ways that enhance their phagocytic potential to various bacteria,[16] we found FK506 in vivo that RIP2 knockout mice did not show reduced inflammation to zymosan. Since RIP2 is required for NOD1/2 signalling, this finding argued against a role for either NOD1 or NOD2 in mediating a gut flora-induced effect in our system.[32] Therefore, NOD1/2 signalling may be important for phagocytosis

but is not needed for neutrophilic inflammation to this agent. Similarly, we found no contribution of the inflammasome components (NLRP3/ASC/caspase 1) or the RNA-sensing RIG-I like receptors https://www.selleckchem.com/products/CP-690550.html in mediating zymosan-induced inflammation. Hence, we show that intestinal flora affect the ability of the immune system to mount neutrophilic inflammation

via the MyD88 pathway. To examine when the MyD88 pathway was required, we took advantage of the ROSA26-Cre system, in which the MyD88 gene could be temporally deleted by the addition of tamoxifen. We showed that for zymosan-induced peritonitis, the presence of MyD88 was not required at the time of challenge. This eliminates the possibility that zymosan Nintedanib (BIBF 1120) needs to signal through MyD88 via TLR2 or IL-1R or any other MyD88-dependent receptor. These data therefore, make a strong case for the necessity of priming by intestinal flora-induced MyD88 activation for zymosan-induced neutrophil migration, before the actual zymosan challenge. Hence a significant finding of this study is that although the MyD88 pathway is essential for creating an innate immune system

that is poised to respond to inflammatory agent, this pathway is not needed at the elicitation phase of an inflammatory response (unless of course the pro-inflammatory stimulus was using MyD88-dependent receptors such as TLRs). An implication of our study is that the set point of the naive (i.e. never exposed to microbes) innate immune system may be anti-inflammatory for many stimuli. However, in conventionally reared mice the immune system is perturbed by exposure to microbial flora in ways that alter the cytokines that are made. As part of this process MyD88-dependent pattern recognition receptor signalling by microbial flora appears to alter this set point in ways that promote inflammatory responses. In summary, we postulate that TLR ligands derived from the intestinal flora constitutively enter the blood and tissues. Here, they prime tissue-resident cells via MyD88 signalling, so that they provide appropriate stimulatory signals that condition the innate immune system to be able to respond to future inflammatory insults in ways that promote neutrophil migration into tissue sites.

The bulk cells were stained for CD4, CD69, or isotype controls an

The bulk cells were stained for CD4, CD69, or isotype controls and analyzed. Cells were gated on CD4. All experiments were performed using C6 Flow Cytometer (Accuri). For abscess induction, mice were injected with a challenge inoculum (200 μL i.p.) consisting of GlyAg and SCC at various dilutions. At day 7, mice were euthanized and scored for abscess formation (≥1 abscess=positive). Abscesses were removed and weighed and the diameter was

measured. Some abscesses were sectioned and stained with H&E, or cryosectioned for confocal microscopy. Abscess digestion was done for 2 h using 2 mg/mL collagenase D at 37°C. The resulting cell suspensions were stained with antibodies and analyzed via flow cytometry. For click here 1400W administration, CGD mice were treated challenged with 50 μg GlyAg and 1:4 SCC and 100 μL of either PBS or 0.5 mg 1400W in PBS. Additional injections of either PBS or 1400W were administered at 6 and 24 h post challenge. Performed as described 47. Briefly, NP-40 cellular extracts

were boiled in standard SDS-PAGE loading buffer containing 1% SDS and Kinase Inhibitor Library price loaded onto a 10% polyacrylamide gel. Protein was transferred to a nitrocellulose membrane and blotted with anti-NOS2 monoclonal antibody. Bands were visualized with a HRP-conjugated secondary antibody and ECL (GE Healthcare) according to the manufacturer’s protocol. Intracellular processing was assessed by incubating splenocytes with 50 μg/mL [3H]GlyAg (PSA) for Sodium butyrate 48 h. Processed radioactive GlyAg was isolated as previously described 20, 23 and analyzed for molecular mass on a SuperDex 75 column in PBS using an Akta® Purifier10 HPLC system (GE Healthcare Biosciences) to measure cleavage compared with the input, unprocessed GlyAg. APCs and CD4+ T cells were purified from WT, CGD, or iNOS−/− splenocytes using microbeads for CD90.2 (for T-cell-depleted APCs) or

CD4 (CD4+ T-cell purification) and magnetic columns (Miltenyi Biotec, Auburn, CA, USA). 1.5×105 APCs and 2.5×105  T cells were added to wells of 96-well plates in triplicates and treated with 100 μg/mL GlyAg in PBS or PBS alone. At various time points, supernatant was removed and analyzed for IFN-γ production via ELISA (eBioscience). Additional experiments were set up as described above but wells were also treated with 0.1 mM 1400W or PBS. 5×106 WT or CGD splenic APCs (T cell and neutrophil depleted by anti-CD90.2 or anti-Ly6G microbeads respectively; Miltenyi Biotec) were transferred i.p. into WT animals which were then challenged with 50 μg GlyAg and 1:7 SCC. After 7 days, mice were scored for abscess formation. 9×104 WT or CGD BM-derived macrophages were plated in triplicates in 96-well plates, then stimulated with 100 ng/mL LPS (Sigma), 100 μg/mL GlyAg±100 μM 1400W for 24 h. Cells were treated with 5 mM ATP (Sigma) 45 min prior to collection of supernatant and IL-1β was detected via ELISA (Biolegend). Data are expressed as mean±standard error of the mean (SEM). Graphs were generated using GraphPad Prism v.

The LPS derivative, monophosphoryl lipid A (MPLA), was created th

The LPS derivative, monophosphoryl lipid A (MPLA), was created through chemical modifications to the lipid A portion of LPS from the Salmonella minnesota R595 strain 20. MPLA adsorbed to alum, named Adjuvant System 04 (AS04) and owned by GlaxoSmithKine, is currently used in both Fendrix for hepatitis B and Cervarix for human papilloma virus 3, 21 vaccines. These vaccines are well tolerated and safe for human use, and generate high titers of antibodies conferring seroprotection to infection 20, 22, 23. In addition, when added to DCs in vitro, MPLA increases cell surface expression of costimulatory molecules as well as migration

to lymph nodes and production of inflammatory cytokines 24, 25. MPLA promotes a Th1-cell immune response in an ovalbumin-specific TCR transgenic system 6, 25. However, in contrast to Mata-Haro et al. 6, we have previously found that MPLA and LPS are relatively weak learn more adjuvants for inducing CD4+ T-cell responses from the polyclonal repertoire of intact mice, while still able to induce strong antibody responses 4, 26. Glucopyranosyl lipid A (GLA) is a new synthetic lipid A agonist that combines six acyl chains with a single phosphorylation site. GLA has been formulated as a proprietary stable

oil-in-water emulsion (GLA-SE) as well as in an aqueous form 27. GLA has already exhibited a good safety profile when tested in combination with the Fluzone vaccine against influenza in monkeys and a recently completed phase I trial 28. In mice,

GLA-SE in combination MG-132 with Fluzone enhanced vaccine-specific antibody responses and hemagglutination-inhibition titers, compared with emulsion alone and GLA as an aqueous formulation with Fluzone. Furthermore, Fluzone plus GLA-SE induced a Th1 type cell-mediated response with IFN-γ and IL-2 production, whereas Fluzone plus the emulsion alone induced a predominant Type 2 response 27, 28. However, the effects of GLA-SE on DCs in vivo have not been examined. To understand how the new chemically defined GLA-SE adjuvant works, we have many studied T-cell and antibody responses to the HIV gag p24 protein delivered within a monoclonal antibody to the DC endocytic receptor (DEC)-205, an uptake receptor, on DCs versus non-targeted gag p24. Protein vaccines are inefficiently captured by antigen presenting cells 29 but targeting vaccine proteins to DEC-205 enhances antigen presentation greater than 100-fold 26, 30, 31. Here we will show that GLA-SE serves as an adjuvant for the induction of antibody and T-cell responses to a HIV gag p24 protein in mice, including Th1 type CD4+ T cells in the intestinal mucosa. We find that DCs are required for adjuvant action, and that the GLA-SE adjuvant quickly renders the DCs functionally mature or immunogenic in vivo. To test the efficacy of GLA-SE as an adjuvant, we immunized mice with anti-DEC-HIV gag p24 or non-targeted gag-p24 protein along with GLA-SE twice i.p. over 4 weeks.

B6 strains Trd1 contains several genes encoding transcription fa

B6 strains. Trd1 contains several genes encoding transcription factors of yet unclear function.

One of them, Btbd9 is a transcription factor containing a POZ domain. Two other members of this family have been described, ThPok and PLZF, implicated, respectively, in CD4 [20] and NKT lineage commitment [21] turning Btbd9 into a candidate for the control of Treg-cell lineage Selumetinib in vitro choice. The Trd1 locus, as it is currently defined, contains Idd16, raising the intriguing possibility that the altered thymic Treg-cell differentiation in NOD vs. B6 mice may be linked to diabetes susceptibility. However, whereas hybrid mice display similarly low levels of Treg cells as B6 mice, they are as susceptible to diabetes as NOD animals. Together, these data therefore strongly suggest that the altered Treg-cell development caused Cilomilast cost by the Trd1 region is functionally dissociated from diabetes onset and progression. The genes

involved in Treg-cell development and diabetes susceptibility are therefore probably, but not necessarily, distinct. Other genetic loci controlling the altered Treg-cell development in NOD vs. B6 mice have been identified [11] but they do not correspond to diabetes susceptibility loci. It appears therefore very unlikely that the quantitatively altered Treg-cell development in NOD mice plays a major role in diabetes susceptibility. In conclusion, we have identified a locus that quantitatively controls thymic Treg-cell development. The atypically high levels of Treg cells developing in NOD mice from appear functionally

dissociated from their susceptibility to diabetes. Identification of the responsible genes and mechanisms will shed light on the still incompletely defined processes involved in the quantitative control of Treg-cell development in the thymus and potentially on commitment of precursors to the Treg-cell lineage. All mice were females of 6–8 weeks. C57BL/6N (B6) mice were purchased from Janvier (Le Genest St Isle, France), C57BL/10 (B10) and NOD strains from Charles River (Les Oncins, France), MHC°, C57BL/6, NOD.B6-R76 (R76), NOD.B6-R156 (R156), and NOD.B6-R115 (R115) mice were bred in our facilities. All experiments involving animals were performed in compliance with the relevant laws and institutional guidelines (INSERM; approval # 31–13, ethical review # MP/02/32/10/03). The following antibodies and secondary reagents were used for phenotypic analysis: PE-Cy7, Pacific Blue, and allophycocyanin-labeled anti-CD4 (GK1.5), FITC, AlexaFluor 700, and allophycocyanin-labeled anti-CD8 (53.6.7), PE, PE-Cy7 and allophycocyanin-labeled anti-CD25 (PC61), PE, and allophycocyanin-labeled anti-TCR (H57), PE, and allophycocyanin-labeled Foxp3 (FJK-16s), biotin-labeled anti-CD122 (5H4), biotin-labeled CD127 (A7R34), (eBioscience, San Diego, CA, USA), PE-labeled Ki67 (B56) (BD Bioscience, NJ, USA).

XLA patients had significantly reduced putative follicular T cell

XLA patients had significantly reduced putative follicular T cells, which may depend on B cells for survival, while no significant alterations were observed in the T cells of those with IgG subclass deficiency or selective IgA deficiency. Common variable immunodeficiency disorders (CVID) are heterogeneous conditions that make up the most common group of clinically significant primary antibody deficiency (PAD). Patients with CVID are characterized by increased susceptibility to recurrent bacterial infection, coupled with low serum immunoglobulin levels and reduced specific antibody

Protease Inhibitor Library molecular weight production in response to vaccination [1]. Patients may also have numerous clinical complications, including enteropathy, lymphoid malignancy, granuloma and autoimmunity, which NVP-BGJ398 mouse have been used recently to classify patients into clinical phenotypes with varying prognoses [2,3]. CVID probably represent a polygenic group of primary antibody deficiency disorders of unknown aetiology [4]. Other PADs include X-linked agammaglobulinaemia (XLA), immunoglobulin (Ig)G subclass deficiency and selective IgA deficiency. Patients with XLA are profoundly antibody and B cell-deficient, and therefore experience recurrent bacterial infections [5]. However, they do not encounter the other clinical complications, common to many CVID patients, which are thought to

relate to the underlying immune dysregulation. There have been suggestions that partial antibody deficiencies, in particular selective IgA deficiency, may share a genetic basis with some types of CVID [6]. This is supported by reports of progression of selective IgA deficiency to CVID in rare patients [6]. Patients with CVID have

a common feature in failure of B cell function, although a number of T cell abnormalities have been described, including reduced naive CD4 T cells [7], reduced proliferative responses to mitogens [8,9], reduced cytokine responses to mitogens and recall antigen [10,11] and reduced T regulatory cells (Tregs) [12–14] in selected patients. A subset of CVID patients are reported to have an increased susceptibility to recurrent viral infections or opportunistic infections that are more associated with T cell defects [7,15], particularly in those patients from consanguineous families [16], suggesting an unknown, autosomal recessive, combined immune Vildagliptin deficiency. Upon antigen encounter, naive T cells undergo a developmental pathway, resulting in the generation of central memory and effector memory T cells [17]. They can be measured in blood by use of the accepted markers, CCR7 and CD45RA [18]. In the early stages of differentiation, T cells express high levels of co-stimulatory molecules CD28 and CD27, which are lost sequentially upon differentiation [19,20]. CD31 and CD45RA co-expression is used to define recent thymic emigrants and correlates well with T cell receptor excision circle (TREC) levels [21].

2% of haemodialysis patients and in 29 5% of controls (P > 0 05)

2% of haemodialysis patients and in 29.5% of controls (P > 0.05). In both groups, Trichophyton rubrum was the most frequently isolated. Mean MIC values of the all studied antifungals for all of isolated dermatophyte strains from patients with ESRD Protein Tyrosine Kinase inhibitor were similar to those obtained in control group (P > 0.05). Terbinafine (TBF) had the lowest mean MIC values for all tested dermatophytes in both groups. We consider that TBF should be the treatment of choice for dermatophytosis in patients with chronic kidney disease, but the dose should be adjusted according

to creatinine clearance and should be monitored for side effects. “
“Rhizopus arrhizus (Mucorales, Mucoromycotina) is the prevalent opportunist worldwide among the mucoralean species causing human infections. On the other hand the species selleck chemicals llc has been used since ancient times to ferment African

and Asian traditional foods and condiments based on ground soybeans. As producer of organic acids and hydrolytic enzymes it is widely applied in food industry and biotechnology. Using a set of 82 strains we studied phylogenetic and biological species boundaries within Rhizopus arrhizus s.l. to test the taxonomic status of R. delemar that was recently separated from R. arrhizus. Sequence analyses based on the internal transcribed spacer region, the gene of the largest subunit of the RNA polymerase II, a part of the actin gene, and the translation elongation factor 1-α as well as amplified fragment length polymorphism analysis were performed. Phenotypic characters such

as enzyme profiles and growth kinetics were examined and the mating behavior was tested. Molecular analyses supported the existence of two phylogenetic species. However, the results of the mating test suggest that the mating barrier is still not complete. No physiological, ecological or epidemiological distinction could be found beside the difference in the production of organic acids. Consequently the status of varieties is proposed for the two phylogenetic species. Because the description of the first described R. arrhizus is considered to be conclusive we recommend the use of Rhizopus arrhizus var. arrhizus and var. delemar. Among the mucoralean species that cause human infections (mucormycoses) Rhizopus arrhizus (syn. R. oryzae) sensu lato is the prevalent opportunist worldwide.[1-5] On the other hand, Rhizopus species are economically very important. Since Enzalutamide purchase ancient times they are used in the preparation of African and Asian traditional foods and condiments. Rhizopus species are included in the dry inoculum that is used as starter culture for the fermentation of soybeans and rice, which are subjected to microbial pre-digestion as for example the Indonesian tempe [6] and ragi,[7] the Korean meju,[8] and different kinds of the Chinese sufu.[9] Strains of Rhizopus arrhizus are widely applied in food industry and biotechnology [9, 10] for the production of organic acids,[7] ethanol, biodiesel and hydrolytic enzymes.