This disparity could be attributed to lack of sensitivity with th

This disparity could be attributed to lack of sensitivity with the assays or related CH5424802 nmr to the timing of blood collection, disease progression or other unknown factors causing an immune response in the host. However, as for IgG levels, measurement of total serum IgE appears to be of no benefit in the preliminary clinical investigation into a suspected host. Conversely, dramatic increases in total IgE levels have been documented for crusted scabies (4,27,33,34). Roberts et al. (3) document 96% of 52 cases with elevated IgE, with 73% 10× above normal levels, and 10% 100× above normal levels. Immunoblotting studies demonstrated that sera from patients

with crusted scabies showed strong IgE binding to 21 unidentified S. scabiei var. canis proteins in comparison with ordinary scabies in which only six proteins were weakly recognized (35). Studies using S. scabiei

var. canis whole mite extract to measure scabies-specific IgE binding observed elevated levels in approximately 50% of patients with active ordinary scabies (36). Recent serology results using S. scabiei var hominis recombinant proteins indicate patients with both crusted scabies and ordinary scabies have a defined IgE and IgG4 response to a number of scabies mite recombinant antigens (Walton S.F., unpublished data). Significantly greater IgE binding to a number of these proteins was observed in the sera of patients with crusted scabies compared with ordinary scabies and control groups, and similarly significantly BVD-523 molecular weight increased IgE binding of the sera of patient with ordinary scabies was observed compared with control sera. Immunohistochemistry MycoClean Mycoplasma Removal Kit staining of mite-infested skin biopsies from patients with crusted scabies has shown human IgG and IgE localizing in the mite gut and flooding the mite burrow (37) (Walton S.F., unpublished data).

In addition, polyclonal antibody to multiple S. scabiei var. hominis recombinant proteins has been demonstrated binding to the gut, external cuticle and burrow of the scabies mite (9,38) (Walton S.F., unpublished data). Immediate wheal reactions have been elicited by intradermal injection of scabies mite extracts in patients with both ordinary scabies and crusted scabies but not normal volunteers (39,40). This response was observed to wane with time, and patients injected 15–24 months after infestation did not react. IgE antibody to allergens induces early allergen-specific mast cell degranulation and contributes to the late-phase reactions by chronic tissue damage via the downstream effect of mast cell mediators and by facilitating allergen presentation to T cells. Mast cell activation also leads to the recruitment and activation of basophils and eosinophils, both of which express the Fc receptor on their surface and can therefore contribute to the IgE-mediated immune response.

The staining showed that the urothelium of the WHHL-MI rabbits wa

The staining showed that the urothelium of the WHHL-MI rabbits was thinner than that of controls in an age-dependent manner and that the amount occupied by muscle fibers decreased, replaced by connective tissues. The fact that bladder urothelium became thinner depending on age was a unique point in the present study. In former studies18–20 of BOO, spinal cord-injured, and bladder ischemia models, CAL-101 supplier urothelium appeared thickened, edematous and hyperemic. One of

the reasons of bladder thickness could be compensation toward urine output resistance and acute or sub-acute experimental preparations by increasing metabolism. However, the present study reflects gradual progression of hyperlipidemia. In the chronic phase of hyperlipidemia, urothelium Y-27632 mw metabolism might shift from a compensation stage to a de-compensation stage, resulting in urothelium thinning observed in old WHHL-MI rabbits. Another possible reason of urothelium thinning might be the presence and degree of inflammation or metabolic changes related to hyperlipidemia, although serum hyperlipidemia alone seems not to cause urothelium thinning.21,23 Another possibility is the effect of oxidative stress. Reactive oxygen species and reactive nitrogen species are generated by ischemia, and they could damage membrane function including L-type calcium channels, alter Ca2+ homeostasis, and increase activities of Ca2+-dependent

enzymes.19 These changes may be related to the urothelium thinning

and increased permeability of urothelium, resulting in bladder dysfunction as described below. In the frequency volume charts, the number of micturition of WHHL-MI rabbits was increased with age, and old WHHL-MI rabbits showed a significantly higher micturition number than controls, although the daily urinary volumes were not different between the groups. The micturition volume of the WHHL-MI rabbits was significantly lower than that of the control in both young and old rabbits (Table 2). In the cysotmetric study, the WHHL-MI rabbits showed non-voiding contractions, shorter interval and lower micturition volume compared to the control group. Although voiding pressures Transmembrane Transproters inhibitor were not significant different between young WHHL-MI and control rabbits, old WHHL-MI rabbits showed significantly lower voiding pressure than controls. The residual urine was not significantly different between the groups (Table 2). In the functional study using isolated bladder smooth muscle strips, the effects of KCl (80 mm), carbachol (10−8–10−4) and electrical field stimulation (EFS: 0.5 ms duration, 1–60 Hz and 2 sec train) were evaluated in both groups. Carbachol and EFS caused concentration- and frequency-dependent contractions in both control and WHHL-MI groups. KCl-induced contractile responses were not significantly different between WHHL-MI and control rabbits.

One milligram chromatin and 3 μg antibody (anti-STAT1, E23 or ant

One milligram chromatin and 3 μg antibody (anti-STAT1, E23 or anti-RANKL, FL-317, taken as a control, Santa Cruz Biotech, check details Dallas, TX) were used for each IP reaction. The immune complexes were pulled down with a mixture of

25 μL Protein A Agarose Beads and 25 μL Protein G Plus Agarose Beads (Santa Cruz Biotech), the crosslink reverted and DNA isolated with a commercially available kit (Macherey Nagel, Düren, Germany). Conditions of PCR and primer sequences are listed in Supporting Information Table 4. The PCR products were resolved in 2% agarose gels, photographed, and ODs of the specific bands were calculated with ImageJ. The binding of STAT1 to the particular GAS element was calculated by dividing the OD for the STAT1

IP by the OD for the respective control IgG IP. BrdU (Sigma-Aldrich) was injected i.p. into MMTVneu Stat1+/+ and Stat1−/− mice in daily dose of 1 mg per mouse [7]. BrdU incorporation into genome was analyzed 3, 24, 72, 96 h or 7 days after the first injection by flow cytometry. The treatment was initiated 2 weeks (3 h time point) or 1 week (other time points) after tumor recognition. Circulating monocytes were depleted by daily i.v. injections XL765 price of clodronate-loaded liposomes (200 μL per mouse; Foundation Clodronate Liposomes, Amsterdam, The Netherlands) [16, 26] for 7 or 11 subsequent days. Control animals were treated with PBS-loaded liposomes. The treatment was initiated 1 week after tumor recognition. Cellularities of blood leukocytes and TAMs were assessed by flow cytometry. Unirradiated MMTVneu Stat1+/+ CD45.1+ CD45.2− recipients were injected i.v. with 2.4–5.5 × 107 BM cells obtained from tumor-free MMTVneu Stat1+/+ CD45.1+ CD45.2+ mice directly after the initial tumor detection in recipient animals [13]. The level of leukocyte chimerism (percentage of CD45.2+ cells) was determined weekly in tail vein blood, the level of macrophage chimerism Resminostat was examined by flow cytometry 2 and 5

weeks after the transfer. The value of monocyte equilibration for the particular animal was calculated according to the formula: Monocyte equilibration = Chimerism (TAM)/Chimerism (CD115+ Gr-1+ monocytes). BM cells isolated from tumor-free MMTVneu Stat1+/+ mice were cultivated for 7 days in tumor cell culture conditioned medium. The adherent cell fraction was gathered by trypsinization, labeled with 5 μM eFluor670 (eBioscience, Vienna, Austria) according to manufacturer’s protocol and injected intratumorally into MMTVneu Stat1+/+ and Stat1−/− hosts (1 × 106 cells in 50 μL PBS per recipient; 4-week-old tumors) under desflurane anesthesia (Baxter, Deerfield, IL). Injected tumors were analyzed 24, 48, 96 h and 7 and 14 days after the transfer by flow cytometry. For adoptive transfer of monocytes, DAPI−CD115+Gr-1+ cells were FACS sorted from BM of tumor-free, 4-month-old MMTVneu Stat1+/+ females.

The evidence of bacterial translocation are: (i) nosocomial infec

The evidence of bacterial translocation are: (i) nosocomial infections have been correlated with indigenous gut bacteria (e.g. Escherichia coli) isolated in blood cultures and (ii) enteric microorganisms have been identified in the blood of cirrhotic patients with spontaneous bacterial

peritonitis 3. Antibiotics are effective in diminishing the colonization and multiplication of bacteria which are translocated from the intestine. However, Erlotinib nmr due to defects of the host’s antibacterial innate immunities, the very small amounts of bacteria that escape from these treatments are sufficient to spread systemically in thermally injured patients. Excessive antibiotic usage BAY 57-1293 mw (amounts and duration) leads to the generation of untreatable strains of bacteria. A new paradigm is needed to treat burn patients with bacterial translocation-related infectious complications. Therefore, we attempted to immunologically control infectious complications caused by bacterial translocation through the recovery of damaged host antibacterial defenses in thermally injured patients. The important roles of macrophages (Mϕs) in antibacterial innate immunity have been described in many papers 4–10. M1Mϕs (IL-12+ IL-23+ IL-10− Mϕs) generated from resident Mϕs by the stimulation with a microbial antigen or cytokines are potent effector cells that kill invaded microorganisms

11–13. In contrast, M2Mϕs (IL-12− IL-23− IL-10+ Mϕs) 14, 15 are shown to be inhibitory on Mϕ conversion from resident Mϕs to M1Mϕs 16. CCL17 and IL-10 released from M2Mϕs are characterized as effector molecules for inhibiting Mϕ conversion from resident Mϕs to M1Mϕs 16. Therefore, M1Mϕs are not generated in hosts

where M2Mϕs predominate 7, 17. CCL2 is a chemokine that attracts and activates mononuclear cells. The necessity of this chemokine for Th2-cell generation has been well demonstrated 18. Thus, CCL2-knockout mice resisted Leishmania major infection 18, while CCL2-overexpressing transgenic mice were susceptible to infections with Listeria monocytogenes or Mycobacterium Ribonucleotide reductase tuberculosis 19. We previously demonstrated that herpes encephalomyelitis 20 and cryptococcal encephalitis 21 are not severely developed in mice depleted of CCL2. Recently, the increased level of CCL2 has been demonstrated in sera of thermally injured patients 22 as well as severely burned mice 23. These mice have already been characterized as mice susceptible to sepsis stemming from Enterococcus faecalis translocation 24. In the subsequent study 25, utilizing CCL2 knockout mice, a role of CCL2 on resident Mϕ conversion into M1Mϕs or M2Mϕs was explored. In contrast to severely burned wild-type mice, M1Mϕs were induced and M2Mϕs were not induced in burned CCL2-knockout mice stimulated with the E. faecalis antigen.

Therefore, pyriproxyfen is a potent ligand for Met, mimicking the

Therefore, pyriproxyfen is a potent ligand for Met, mimicking the function of JH and thus preventing adult transition. Previous studies in a mouse model have indicated that pyriproxyfen is stable and safe up to 5 g/kg when administered orally and is rapidly biodegraded after administration [4]. However, the effects of large doses of pyriproxyfen on mammalian immune response are still unknown. Therefore, we explored whether large doses of pyriproxyfen affect the immune response. We aimed to determine the IgG immune response to pyriproxyfen and the widely used model antigen OVA. We also monitored other aspects

of the immune profile in response to pyriproxyfen, including PLX4032 molecular weight IgG subtypes such as IgG1 or IgG2a, IgE production and cytokines. The four-week-old female BALB/c mice used in this study were purchased from Kyudo (Saga, Japan) and housed in a controlled specific pathogen-free environment

with a 12 hr light/dark cycle (lights on from 07:00 to 19:00) and temperature and humidity controlled to 23 ± 2°C and 55 ± 5%, respectively. Feed (CE-2; Clea Japan, Tokyo, Japan) and water were provided ad libitum. All procedures related to the animals and their care were approved (Certificate No. 1104474) by the Laboratory Animal Care and Use Committee of Fukuoka University. For immunization, OVA (Sigma–Aldrich, St. Louis, MO, USA) was dissolved in PBS at a concentration of 5 μg/mL. Initially, 1.9, 5.8 and 9.7 mg of pyriproxyfen (Fig. 1) (Wako Pure Chemical Industries, Osaka, Japan) Etofibrate were dissolved in 100 μL of 99% ethanol and made up to 1 mL with PBS. Subsequently, 100 μL of each pyriproxyfen solution was diluted with an equivalent volume of OVA solution to provide the desired concentrations of 3, 9 and 15 mM, respectively. The control sample was made by using PBS to create 10% ethanol and then diluting this down to 5% ethanol with OVA solution to obtain the desired concentration. Imject Alum (alum; Thermo Scientific, Rockford, IL, USA) solution was prepared by mixing

1 μL of alum (40 μg/μL) in 100 μL of OVA solution according to the manufacturer’s protocol and finally diluting to 200 μL with PBS to obtain the desired concentration of 200 μg/mL. All immunizations were performed by intraperitoneal injection in a volume of 200 μL. To evaluate OVA-specific total IgG immune responses induced by pyriproxyfen, groups of 17 mice were immunized on Weeks 0, 3 and 6 with OVA in 5% ethanol (negative control), OVA containing alum (positive control) or pyriproxyfen (15 mM). Blood samples were collected from each mouse via the tail vein at 3, 5, 7 and 8 weeks. After collection, blood samples were centrifuged at 12,000 rpm for 15 min to obtain sera. The sera were heat-inactivated at 50°C for 30 min and kept at −20°C until use. Below is a brief description of detection by ELISA of OVA-specific total IgG immune responses in sera.

While these differences

in tissue microRNA expression are

While these differences

in tissue microRNA expression are interesting, defining whether changes are disease-specific or fundamental to disease Atezolizumab cost pathogenesis remains a major challenge. Transition of epithelial to mesenchymal cells is recognized as a substantial contributor to the development of kidney fibrosis.63 Epithelial mesenchymal transition (EMT) describes a reversible series of events during which epithelial cells undergo morphological changes and acquire mesenchymal characteristics. These events involve epithelial cells losing cell–cell contacts, apical-basal polarity and epithelial-specific junctional proteins such as E-cadherin while acquiring mesenchymal markers including vimentin and N-cadherin.64 The end result is that immobile epithelial cells revert to an immature undifferentiated phenotype with enhanced migratory ability reminiscent of an earlier development stage and can embed in interstitium.

EMT is known to be involved in implantation, embryogenesis and organ development. It also has been shown to associate with cancer progression and metastasis.65 EMT has been suggested to contribute to kidney fibrosis, which is defined as an excessive deposition of extracellular matrix, mediated predominantly by fibroblasts and mesenchymal cells, click here leading to structural destruction and renal failure. The possible sources of fibroblasts and mesenchymal cells in kidney fibrosis include de novo proliferation of resident tissue fibroblasts, circulating fibrocytes from bone marrow or perivascular smooth muscle cell expansion (myofibroblasts). It has been demonstrated recently that a

large proportion of interstitial fibroblasts actually originate from tubular epithelial cells via EMT in diseased kidney.66–68 Several studies have now found that EMT is regulated by miRNAs, notably the miR-200 family and miR-205.69–72 These miRNAs have been implicated in the EMT process occurring in cancer development.72 The miR-200 family and miR-205 are downregulated in Madin Darby canine kidney cells undergoing TGFβ-induced EMT.69 Their decrease with TGF-β exposure is linked to the EMT response. Evidence has recently emerged that the miR-200 Fludarabine family and miR-205 are elevated in patients with hypertensive nephrosclerosis.58 Recently, Yamaguchi et al. have proposed an important mechanism for podocyte dehiscence and loss through EMT.73 In other disease processes, particular miRNAs were found to be substantially altered during EMT.65 Future work is required to determine the significance of miRNA involvement in EMT during the development of diabetic nephropathy. Renal transplantation is the treatment of choice for patients with end-stage kidney disease because of superior survival and quality of life when compared with patients on maintenance dialysis. Despite improvements in immunosuppression, acute rejection (AR) and chronic allograft nephropathy remain major challenges.

[85-88] Other analogues of αGalCer that are able to skew conventi

[85-88] Other analogues of αGalCer that are able to skew conventional CD4+ T-cell responses more towards either a Th1- or a Th2-like profile will be introduced into clinical studies. In the near AZD4547 order future, it may be possible to differentially activate or inhibit type I and type II NKT cells for the development of novel immunotherapeutic protocols in the treatment

and prevention of autoimmune diseases. Mechanisms by which NKT cell subsets modulate immunity generally follow events and their interactions with other immune cells after activation by their respective lipid antigens, e.g. αGalCer and sulphatide for type I and type II NKT cell subsets, respectively. As DCs play a crucial role not only in the activation of NKT cells but also may be central to their role in the regulation of immune responses, we will first consider NKT–DC interactions and their control of NKT cell-mediated modulation of

autoimmune disease. The advent of intravital imaging now enables the cell dynamics and function of T-cell–DC interactions to be investigated in vivo. Considerable new information provided by the application of 2P microscopy has been reported about the cellular and molecular dynamics of conventional CD4+ and CD8+ T-cell–DC interactions in vivo.[51, 54] While NKT–DC interactions are also central to the regulation of many immune responses Nutlin-3 manufacturer and diseases, less is currently known Suplatast tosilate about the dynamics of movement, recirculation and interaction between NKT cells and DCs in vivo.[51, 54] Some recent observations made using in vivo imaging of NKT–DC interactions are presented in Table 6. A key finding is that bidirectional NKT

cell–DC interactions can elicit and amplify innate and adaptive immune responses. Hence, intravital imaging has identified a central role for NKT cells in the context of other immune cells during various immune responses.[51, 54] This further underscores the importance of learning more about different NKT cell subsets and developing more experimental approaches to track these NKT cell subsets by in vivo imaging. In such studies, it is essential to monitor before and after antigen stimulation: (i) the tracking patterns of type I and type II NKT cells from blood into peripheral tissues (e.g. lymph nodes, spleen, liver), (ii) the differences in the number, time and stability of encounters of these NKT subsets with DCs, (iii) the time and sites of migration of these subsets after DC interaction, and (iv) these various parameters in environments of health (e.g. normal disease-free mouse strains) or disease (e.g. mouse strains that develop different autoimmune diseases, as described below).

(28) All procedures were approved and carried out in accordance

(28). All procedures were approved and carried out in accordance with the Animal Care Committee of Virginia Tech. Equal numbers of female and castrated male lambs were represented in each breed. Lambs were born in January, weaned at approximately 70 days of age and maintained on native pastures until the start of the study in June. Mean body weights in June averaged 19·9 and 27·5 kg for hair and wool lambs respectively. These pastures were known to be contaminated with H. contortus and provided prior

exposure to the parasite. Measurements taken in this study therefore reflect acquired rather than innate immune responses. Levels of parasitaemia were not quantified before the start of the study, but signs of Trichostatin A molecular weight CFTR modulator clinical haemonchosis were not observed. In addition, lambs were infected with 3000 H. contortus infective third stage larvae (L3) weekly for four consecutive weeks prior to the start of the experiment to further standardize previous exposure to the parasite. One week after receiving the last dose of infective larvae (i.e. at day −11 relative to experimental parasite challenge), lambs were moved to drylot

and treated with levamisole (8 mg/kg body weight) and fenbendazole (10 mg/kg body weight) on days −11 and −8 to remove existing worms. No eggs were detected in lamb faecal samples taken immediately prior to experimental infection. Small numbers of coccidial oocysts were seen throughout the study, but symptoms

of coccidiosis were not apparent. Twelve lambs of each breed were randomly assigned to receive experimental parasite infection and were moved to raised indoor pens on day −4, de-wormed again at day −3 to remove any remaining worms and orally infected with 10 000 H. contortus L3 larvae on day 0. These lambs remained in these pens until the end of the study. For reasons of space limitations, the 14 control lambs of each breed remained in drylot for an additional 2 weeks. Control lambs were moved to indoor pens on day 7 relative to infected animals and de-wormed on day 8 to approximate treatment of infected animals. However, control lambs were accidentally infected on day 11 and therefore required additional de-worming on days 12 and 14 to prevent establishment of Sorafenib mouse infection. At all time points assessed, no parasitic nematode eggs were present in the faeces of control animals, but this accidental transient exposure to L3 larvae changes interpretations of responses in control lambs in ways that will be discussed below. Infected animals of each breed (n = 6) were euthanized at 3 or 27 days post-infection (p.i.). These days were selected to represent responses to larvae (day 3) and adult worms (day 27). Control animals of each breed were sacrificed on days 17 (n = 4), 27 (n = 6) and 38 (n = 4), relative to day 0 of infected animals, corresponding to days 6, 16 and 27 following exposure to the parasite and subsequent immediate de-worming.

DNA was extracted from the remaining cells using the Puregene DNA

DNA was extracted from the remaining cells using the Puregene DNA purification kit (Flowgen, Ashby de la Zouch, UK). The DNA was stored at −20°C until required for analysis. When the DNA was thawed its concentration was determined by optical density readings using a spectrophotometer and aliquots of 50 ng was removed for use in real-time PCR experiments. Human sjTREC and albumin (ALB) levels were quantified using real-time PCR performed on the Roche Light Cycler (Roche Diagnostics, Lewes, UK). A PCR reaction

mixture containing 50 ng of DNA, 0·5 µM of forward and reverse primers and 2× SYBR Green mix (Qiagen, Crawley, UK) in a final reaction volume of 10 µl, using selleck inhibitor sterile water. The primer sequences used were sjTREC forward: GGC AGA AAG AGG GCA GCC CTC TCC AAG and reverse: GCC AGC TGC AGG GTT TAG G or ALB forward: CTA TCC GTG GTC CTG AAC CAG TTA TG and reverse: CTC TCC TTC TCA GAA AGT GTG CAT AT, which produced amplicons of 195 base pairs (bp) and 206 bp, respectively. Real-time PCR conditions on the Light Cycler were 95°C for 15 min, followed by 45 cycles at 95°C for 15 s, 61°C for 30 s and 72°C for 20 s (fluorescent acquisition). The albumin reaction was performed as described above, except that the annealing temperature was changed to 60°C. The 195 bp and 206 bp PCR products were identified by melting-point analysis.

A standard curve generated from a serial dilution of known concentration of sjTREC or albumin plasmid was used to enable calculation of the number of detectable molecules from the test samples. The copy number of sjTREC and ALB

(x) was calculated using the following equations: ysjTREC = −3·468x + 42·09 MG-132 nmr and yALB = −3·374x + 40·593, where the cycle threshold (Ct) value is substituted as y. A standard concentration of 1 × 104 sjTREC or ALB molecules was included to determine variance between each run and comparability of the sample. All samples were run Sulfite dehydrogenase in duplicate and an average of the result used for statistical analysis. Where Ct values of the duplicates were greater than 1·5 cycles the samples were rerun. From these readings we obtained a value of sjTREC per 50 ng of DNA. The amount of DNA obtained from the sample of PBMC was known, so we could calculate the number of sjTREC in the PBMC sample. Because sjTREC can be derived only from T cells and we had determined the number of CD3+ T cells by immunophenotyping in the sample, we could ascribe a definite value of sjTREC/T cell to the sample. The results of the descriptive analysis are presented for numerical variables in the form of means ± standard deviation (s.d.) and median for age; sample sizes and percentages calculated for categorical outcomes. Subjects’ characteristics and blood sample components were compared with respect to the age group. Statistical tests used for the comparative analysis were chosen according to the type of variable, the sample size under consideration and the number of group compared.

Hence, intraorally, the pathogenic yeast may undergo a brief expo

Hence, intraorally, the pathogenic yeast may undergo a brief exposure to antifungal drugs. The objective of this study was to investigate the effect of brief exposure to sub-lethal concentrations of these antifungals on the germ tube formation and CSH of C. dubliniensis. After determining the minimum inhibitory concentration of the

drugs, 20 oral isolates of C. dubliniensis were exposed to sub-lethal concentrations of these antifungals for 1 h. Following this brief exposure, the drugs were removed, and following subsequent incubation in a germ tube inducing medium and exposure to bi-phasic hydrocarbon assay, the germ tube formation and CSH of these isolates was quantified respectively. Compared with controls, exposure to amphotericin B almost completely suppressed the ability to

form germ tubes with a mean percentage reduction of 95.91% (P < 0.0001), whereas ketoconazole and fluconazole also significantly inhibited germ tube formation but to a lesser degree with a mean percentage reduction of 18.73% and 12.01% respectively (P < 0.05). Compared with controls, exposure to amphotericin B and ketoconazole elicited a significant suppression on CSH with a mean percentage reduction Trametinib in vitro of 33.09% and 21.42%, respectively (P < 0.001), whereas exposure to fluconazole did not elicit a significant suppression on CSH (9.21%; P > 0.05). In clinical terms it appears that, even a short exposure to sub-lethal concentrations of these drugs, a situation all too familiar in the oral environment, would continue to exert an antifungal effect by suppressing the pathogenic potency of C. dubliniensis. “
“Antimicrobial photodynamic therapy (aPDT) is an emerging alternative to treat infections based on the use of photosensitisers (PSs) and visible light. To investigate the fungicidal effect of PDT against azole-resistant Candida albicans strains using two PSs with a different mechanism of action, hypericin (HYP) and 1,9-dimethyl

methylene blue (DMMB), comparing their efficacy and the AMP deaminase reactive oxygen species (ROS) species involved in their cytotoxicity. Azole-resistant and the azole-susceptible C. albicans strains were used. Solutions of 0.5 and 4 McFarland inoculum of each Candida strain were treated with different concentrations of each PS, and exposed to two light-emitting diode light fluences (18 and 37 J cm−2). Mechanistic insight was gained using several ROS quenchers. The minimal fungicidal concentration of HYP for ≥3 log10 CFU reduction (0.5 McFarland) was 0.62 μmol l−1 for most strains, whereas for DMMB it ranged between 1.25 and 2.5 μmol l−1. Increasing the fluence to 37 J cm−2 allowed to reduce the DMMB concentration. Higher concentrations of both PSs were required to reach a 6 log10 reduction (4 McFarland). H2O2 was the main phototoxic species involved in the fungicidal effect of HYP-aPDT whereas 1O2 was more important for DMMB-based treatments.