, 2005; Jurcisek & Bakaletz, 2007; Weimer et al , 2010; Byrd et a

, 2005; Jurcisek & Bakaletz, 2007; Weimer et al., 2010; Byrd et al., 2011; Nguyen et al., 2011) and direct analysis of human clinical specimens where identification is more challenging (Hall-Stoodley et al., 2006; Bjarnsholt et al., 2009a, b; Nistico et al., 2011). This has prompted the development of proposed criteria that can be used to demonstrate biofilm in vivo along with molecular methods that can distinguish specific

microorganisms in situ ex vivo. Where in vitro biofilms are grown de novo from isolated cultures and the development and molecular components of extracellular polymeric substances (EPS) are known to be specifically of bacterial origin, host-derived components in experimental in vivo infections may be morphologically similar to microbial biofilms necessitating the distinction of microbial biofilms in complex host buy Romidepsin environments in an animal model. Clinical biofilm-associated infections (BAI) are even more challenging, because the infectious agents are often unknown, and pathologically significant biofilm infections need selleck compound to be distinguished from microbial colonization with nonpathogenic organisms. A core definition of a biofilm

accommodating the diversity of BAI is needed. A biofilm is often defined as ‘an aggregate of microbial cells adherent to a living or nonliving surface, embedded within a matrix of EPS of microbial origin.’ Biofilm EPS is an amalgam of extracellular macromolecules including nucleic acids, proteins, polysaccharides, and lipids (Flemming & Wingender, 2010). Within the biofilm, microbial cells are physiologically distinct from planktonic or single, free-floating cells of the same organism; however, at present, this crucial distinction is not a simple determination that can be evaluated by the tests and examinations usually employed in medical diagnostic work-ups. Classically, bacteria exhibit recalcitrance to antibiotics when

they are in biofilms. Pseudomonas aeruginosa exhibits higher tolerance to tobramycin and colistin when it is surface-attached in vitro Tyrosine-protein kinase BLK (Nickel et al., 1985; Alhede et al., 2011), compared with when it is planktonic. Although biofilms are typically described as being attached to a surface, they may also form at interfaces of spatially distinct microenvironments and as suspended aggregates. For example, an air–liquid interface can result in an aggregated mat of microbial cells just as well as those found on a solid surface-liquid interface. The notion that it is sufficient for a biofilm to be an aggregated mass of cells floating in liquid is supported by the observation that aggregates of a methicillin-sensitive strain of Staphylococcus aureus exhibit a much higher tolerance to the antibiotic oxacillin than single, planktonic, cells (Fux et al., 2004), and aggregates of P.

The establishment of an effective and regulated immune response d

The establishment of an effective and regulated immune response directed against Leishmania is critical for resolution of infection PI3K Inhibitor Library in vivo and limitation of pathology. Leishmaniasis is considered as an emergent and re-emergent

disease and encompasses visceral and tegumentary forms, including cutaneous and mucocutaneous forms [1–3]. Infection with the protozoa parasite Leishmania braziliensis can cause several clinical forms of disease, and in Brazil it is responsible for at least two major clinical forms: cutaneous (CL) and mucosal (ML) leishmaniasis [1,2]. Human tegumentary leishmaniasis is usually limited to the skin and lymphatic system, but it may recur in the mucous membranes of the mouth, nose or pharynx in ML [4,5]. In experimental CL, development of protective immunity is dependent upon the generation Opaganib cost of specific cytokine-producing T cells with a regulated T helper type 1 (Th1)-like profile [6,7]. In the majority of CL patients, effective cell-mediated immunity, as evidenced by a positive delayed-type hypersensitivity (DTH) reaction [8,9], as well as production of interferon (IFN)-γ and tumour necrosis factor (TNF)-α by peripheral T cells and cutaneous lesion

cells found in inflammatory infiltrates, show the same profile seen in experimental models [10–13]. IFN-γ is an important cytokine that activates infected macrophages to check eliminate parasites and improve antigen processing and presentation, as well as aiding in creating an effective microenvironment for generation of Th1 T cells. At the same time, the lack of proper regulation of this response may lead to the formation of exacerbated lesions, as seen in mucosal disease [12–14]. Recently, we demonstrated that Leishmania-specific T cells from CL patients displayed a regulated inflammatory T cell response

as measured by correlation between the frequency of proinflammatory (IFN-γ and TNF-α) and anti-inflammatory (IL-10) cytokine-producing cells [10,13]. Interestingly, our group also observed positive correlations between immunological and clinical measurements in CL patients. This work demonstrated a positive correlation between the Montenegro skin test (MST) size and the frequency of recent activated CD4+ T cells analysed ex vivo. Moreover, the larger the lesions, the higher the frequencies of inflammatory cytokine (IFN-γ or TNF-α)-producing Leishmania-specific lymphocytes [15]. Given that specific T cell responses against Leishmania antigens play a critical role in the formation of protective and pathogenic immune responses in human leishmaniasis, it is clear that the elucidation of which T cell subpopulations are involved in the response will aid in the identification of possible dominant antigens used by the human immune response.

Therefore, an assay that is

capable of exactly assessing

Therefore, an assay that is

capable of exactly assessing functional activity with reliable reproducibility would be based on optimal conditions including bacterial growth phase, number and culture conditions. We developed the in-house ABA-ELISA to determine whether the MBS of BabA and SabA adhesins correlated with clinical manifestation in 90 of 120 isolates whose genetic status had been determined. The optimal quantity of bacteria for eliminating selleck chemical any dose-dependent effect was determined to be 1.0 × 109 CFU/ml. Bacterial phase variation was rigorously examined in a liquid medium, demonstrating that the appropriate growth phase is approximately 24 hr after culture, corresponding to late exponential to early stationary phases. When these conditions were exactingly optimized in the in-house ABA-ELISA, it repeatedly provided stable binding intensity of both adhesins at their strongest. The greatest amount of transcripts

at 24 hr was confirmed by semi-quantitative reverse transcription-PCR using NCTC11637 and HPK5 strains (data not shown). The specificity of mechanical binding for BabA-Leb and SabA-sialic acid was verified with the digestive enzymes and isogenic mutants, HPK5BA2 and HPK5SA4, respectively. In particular SabA-MBS of this assay, the NCTC11637 strain was likely to show less specific binding than HPK5 even after long-term digestion with neuraminidase, suggesting that EPZ6438 other adhesion molecules (31, 32) and unknown factors might interfere with the assay of SabA-MBS. According to the in-house ABA-ELISA, the degree of both MBS varied between individual strains. However, the degree of BabA-MBS was

significantly greater in the cancer group than in the non-cancer group (P= 0.019), indicating that a high BabA-MBS might be related to development of severe gastric disorders, including gastric cancer. In addition, PD184352 (CI-1040) the positive correlation between BabA- and SabA-MBSs was stronger in the cancer than in the non-cancer group. Fascinatingly, the average SabA-MBS was significantly larger in the BabA-high-binding group than in the BabA-low-binding group (P < 0.0001), but not vice versa. Furthermore, the MBS of either BabA-high-binding or SabA-high-binding groups in cancer or non-cancer groups were statistically analyzed. No pattern was significant but there was a tendency towards greater BabA-MBS in cancer than in non-cancer subgroups of the SabA-high-binding group (P= 0.0856) (data not shown). These results indicate that BabA-MBS has an effect on the function of SabA-MBS, but that SabA-MBS has no effect on the function of BabA-MBS, suggesting that situations associated with enhancement of BabA-MBS in isolates’ adaptation and colonization in the individual stomach in turn may induce and/or stimulate SabA production.

7b) Antibody stimulation was used instead of antigen stimulation

7b). Antibody stimulation was used instead of antigen stimulation to demonstrate the direct effect of Y-27632 research buy the inhibitor on

Th1 cells and to discount the indirect effects on APCs. Inhibition of JNK activity by SP600125 was sufficient to suppress the proliferation of the KLH-specific Th1 cells, indicating that Th1 cells used in this model are no different from primary CD4+ T cells in that the inhibition of JNK alone is sufficient to block proliferation. In conclusion, p21Cip1-mediated suppression of JNK activity in anergic Th1 cells is a novel potential mechanism that could account for the proliferative unresponsiveness found in these cells. This manuscript examined the role of p21Cip1 in maintaining the proliferative unresponsiveness found Selleckchem Raf inhibitor in Th1 cells anergized by exposure to antigen and n-butyrate. The results presented in this work suggest that p21Cip1 functions in these Th1 cells primarily through the inhibition of members of the MAPK family rather than inhibition of its classical interaction partners,

namely cdk. p21Cip1 has long been described as a negative regulator of the cdk-mediated G1 to S phase transition.25 However, based on the association pattern of p21Cip1 and cdk in anergic compared to control Th1 cells, the p21Cip1 inhibition of cdk activity does not appear to be the primary mechanism for cell cycle inhibition. Instead, the results suggest that p21Cip1 specifically interacts with p-JNK and p-c-jun in antigen-restimulated anergic Th1 cells. The role of p21Cip1 in the normal cell cycle has been at

variance in different studies. Eventually, a dual role has been suggested for p21Cip1 in which low levels of p21Cip1 facilitated the cell cycle by promoting cdk–cyclin complex assembly whereas high levels inhibited cdk activity.25–27 The role of p21Cip1 in normal T-cell activation is not clear. T cells from the p21Cip1-deficient mice exhibited enhanced homeostatic proliferation and increased Acyl CoA dehydrogenase the frequency of cycling T cells.28 Another study using p21Cip1-deficient mice reported that p21Cip1 did not affect primary proliferation of naïve T cells, but was required for the regulation of activated/memory T-cell proliferation.29 In the present study, control Th1 cells stimulated for 36 hr with antigen contained appreciable amounts of p21Cip1, much of which associated with cdk2, cdk4 and cdk6. It would therefore seem likely that at least some of the regulatory effect of p21Cip1 in stimulated control Th1 cells in our system involves interaction with cdk. The amount and timing of p21Cip1 induced in activated T cells may be sufficient to promote cdk–cyclin assembly but not enough to block cdk activity. Alternatively, p21Cip1 may be up-regulated in activated T cells as a fail-safe mechanism in case some kind of cellular stress necessitates regulation of DNA replication or repair.

41 Mesenchymal stem cells have been found to exert a therapeutic

41 Mesenchymal stem cells have been found to exert a therapeutic effect in a wide array of diseases, acting through their unique immunomodulatory abilities that can alter the pro-inflammatory course of injury. This may involve the secretion of paracrine factors that dampen inflammation and in turn promote tissue remodelling and repair.39 Their ability to modulate the immune response R788 mw in vivo was first reported by Bartholomew et al.42 who demonstrated that the intravenous administration of allogeneic MSC to baboons resulted in prolonged skin-graft survival. MSC have also been reported to be beneficial in an autoimmune disease setting. In a mouse model of multiple sclerosis termed autoimmune encephalomyelitis (EAE), the administration

of MSC at the onset of disease induced peripheral T-cell anergy against the pathogenic peptide myelin oligodendrocyte glycoprotein (MOG), resulting in the amelioration of the progression of injury.43 Furthermore, the administration

of MSC to mice with diabetes type 1 resulted in the recovery of damaged insulin producing pancreatic islets and β-cells and decreased blood glucose levels.44 Two mechanisms appear to be aiding this recovery. In addition to the production of trophic growth factors, MSC also inhibit the β-cell specific T-cell immune reaction.45 GSK-3 inhibitor In a mouse model of lung fibrosis, MSC reduced local inflammation, collagen accumulation and consequently fibrosis.46 Subsequent studies demonstrated that MSC conferred this protection by inhibiting the release of interleukin (IL)-1α and tumour necrosis factor (TNF)-α through the secretion of IL-1 receptor antagonist (IL-1RA).47 The local injection of MSC to mice following coronary ligation induced the regeneration of cardiac tissue and improved myocardial function.48 Following intravenous administration, MSC preferentially homed to the infarct site where they promoted angiogenesis and myogenesis and mediated myocardial repair

via paracrine mechanisms.49 The first phase I clinical trial in humans involved the intravenous infusion of MSC into patients with hematologic malignancies in complete remission resulting in no adverse events.50 Subsequent trials in breast cancer Ureohydrolase patients showed that MSC infusion, following high dose chemotherapy and peripheral-blood progenitor-cell infusion resulted in enhanced hematopoietic engraftment and recovery.51 The immunosuppressive effects of MSC have also effectively been used to treat a leukaemia patient with severe treatment-resistant grade IV acute graft-versus-host disease (GvHD).52 Following the promising results obtained from these trials, MSC have since been clinically trialled in a diverse range of other conditions. Numerous phase I–II and III clinical trials exploring the therapeutic potential of MSC in conditions such as diabetes type 1, myocardial infarction, ischemic stroke, Crohn’s disease, cirrhosis and osteoarthritis have been completed or are currently in progress (see http://www.

The results revealed that IL-13 significantly enhanced C/EBP-α/CO

The results revealed that IL-13 significantly enhanced C/EBP-α/COX-2 expression and PGE2 production in LPS-treated microglial cells. Paradoxically, IL-13 abolished C/EBP-β/PPAR-γ/HO-1

expression. IL-13 also enhanced ER stress-evoked calpain activation by promoting the association of C/EBP-β and PPAR-γ. SiRNA-C/EBP-α effectively reversed the combined LPS-activated caspase-12 activation and IL-13-induced apoptosis. In contrast, siRNA-C/EBP-β partially increased microglial PI3K inhibitor cell apoptosis. By NeuN immunochemistry and CD11b staining, there was improvement in the loss of CA3 neuronal cells after intrahippocampal injection of IL-13. This suggests that IL-13-enhanced PLA2 activity regulates COX-2/PGE2 expression through C/EBP-α activation. In parallel, ER stress-related calpain downregulates the PPAR-γ/HO-1 pathway via C/EBP-β and leads to aggravated

death of activated microglia via IL-13, thereby preventing cerebral inflammation and neuronal injury. Microglial cell Selleck Navitoclax activation is exquisitely sensitive to brain injury and diseases that contribute to neuronal cell death (e.g. repeated infection, traumatic brain damage, and stroke). Such activation likely plays a crucial role in inflammatory neuronal injury and chronic neurodegenerative diseases [1]. Anti-inflammatory medications may be protective against brain damage. Emerging evidence indicates that endoplasmic reticulum

(ER) stress plays a pivotal role in the pathogenesis of neurodegeneration [2]. The ER activates the unfolded protein response, a signaling pathway for adaptive response, which initially exerts a protective effect by upregulating specific ER stress-regulated genes and inhibiting general protein translation [3, 4]. However, severe or prolonged ER stress results in cell death via apoptotic signaling, ultimately leading to neurodegeneration. A previous study has shown that IL-13 downregulates peroxisome aminophylline proliferator-activated receptor gamma/heme oxygenase 1 (PPAR-γ/HO-1) via ER stress-stimulated calpain activation. Thus, IL-13 may reduce chronic brain inflammation [5]. This finding is consistent with the findings of Yang et al. [6] showing that IL-13 enhances cyclooxygenase-2 (COX-2) expression in activated rat brain microglia, thereby reducing brain inflammation. Recently, Kawahara et al. [7] suggested that intracerebral microinjection of IL-4/IL-13 reduces β-amyloid accumulation on the ipsilateral side and improves cognitive deficits in young amyloid precursor protein 23 mice. However, the mechanisms underlying how IL-13 regulates activated microglia and its relationship with the dampening of neuronal death have not been well elucidated. Studies on the relationship between glial activation and neurotoxicity have identified several molecular targets for transcription factor research.

92 Moreover, polymorphisms in not only STAT3, but also in IL23R

92 Moreover, polymorphisms in not only STAT3, but also in IL23R

and JAK2 loci, correlate with Crohn’s disease.93–95 Therefore, appropriate activation of the STAT proteins is clearly required for the development of a healthy immune response. Interestingly, several studies show abnormal expression of SOCS proteins in autoimmune diseases. In particular, SOCS1 mRNA is elevated in patients who present with systemic lupus erythematosus96 and rheumatoid arthritis,97 and single nucleotide polymorphisms in SOCS1 are associated with multiple sclerosis98 and coeliac disease.99 All of these autoimmune pathologies are characterized by increased IL-17 secretion, which would be consistent with the fact that SOCS1 promotes the development of Th17 cells. Compellingly, Trametinib mouse the correlation between SOCS3 expression and the severity of atopy is also apparent in patients. Markedly High Content Screening elevated SOCS3 expression is observed in skin samples from patients suffering from severe atopic dermatitis (AD) when compared with individuals with normal skin or with the Th1-mediated condition psoriasis.100 Furthermore, specific haplotypes of the SOCS3 gene have been linked with AD in two independent Swedish childhood cohorts

and SOCS3 mRNA is more highly expressed in AD skin.101 The detection of elevated SOCS3 expression in peripheral T cells and in AD skin may be of particular relevance because the SOCS3 gene is located on chromosome 17q25, one of the established AD genetic loci.102 Similarly, SOCS3 expression in T cells positively correlates with the severity of asthma and AD,33 whereas elevated SOCS3 mRNA levels and polymorphisms within Avelestat (AZD9668) the SOCS3 locus are found in patients with AD.101 Asthmatics also present with polymorphisms within the SOCS1 promoter, consistent with the fact that SOCS3 and SOCS1 regulate Th2 differentiation.103

The correlation between elevated SOCS1 expression and asthma severity in patients suggests that SOCS1 may inhibit IFN-γ-dependent Th1 differentiation, thereby enhancing Th2-mediated pathology.104 Of note, disruption of SOCS2 expression increases murine susceptibility to atopy but whether this is of relevance in patients has yet to be determined.59 Taken together, these different studies confirm the importance of SOCS proteins in the regulation of human pathogenic immune responses. Clearly, both STATs and SOCS are key regulators of lineage commitment and collaborate to tightly regulate CD4+ T-cell polarization. As with STATs, SOCS often exert opposing effects and may cross-regulate one another,59,61,105,106 and although murine null models exemplify this cross-compensation, this may well reflect reality because SOCS proteins are differentially expressed in individual CD4+ lineages.

The correlation between CD28null/CD8+ T cells and FEV1 suggests t

The correlation between CD28null/CD8+ T cells and FEV1 suggests that enumeration of this subset may further simplify monitoring of potential BOS development in patients. However, one must also be cautious in drawing definite conclusions selleck products from this small cross-sectional study, particularly the exact role that CD4/CD28null and CD8/CD28null play in the development of BOS, and further longitudinal patient studies are required to confirm these findings. In

conclusion, BOS is associated with down-regulation of CD28 and up-regulation of alternate co-stimulatory molecules on steroid-resistant CD4+ and CD8+ T cells. Early therapeutic targeting of alternate T cell co-stimulatory molecule expression following transplant

and monitoring response using these assays may elucidate the exact role played by alternate co-stimulatory molecules in lung transplant rejection and may possibly help to manage patients with BOS, where current treatments are ineffective and following progress is limited to lung function. This study was funded by a National Health and Medical Research Council grant. The authors have no conflicts of interest. “
“We have previously described a protein termed selleck chemicals Shigella enterotoxin 2 (ShET-2), which induces rises in short-circuit current in rabbit ileum mounted in the Ussing chamber. Published reports have postulated that ShET-2 may be secreted by the Shigella type III secretion system (T3SS). In this study, we show that ShET-2 secretion into the extracellular space requires the T3SS in Shigella flexneri 2a strain 2457T and a ShET-2–TEM fusion was translocated into epithelial cells in a T3SS-dependent manner. The ShET-2 gene, sen, is encoded downstream of the ospC1 gene of S. flexneri, and we show

that sen is cotranscribed with this T3SS-secreted product. Considering that T3SS effectors have diverse roles selleck in Shigella infection and that vaccine constructs lacking ShET-2 are attenuated in volunteers, we asked whether ShET-2 has a function other than its enterotoxic activity. We constructed a ShET-2 mutant in 2457T and tested its effect on epithelial cell invasion, plaque formation, guinea pig keratoconjunctivitis and interleukin 8 (IL-8) secretion from infected monolayers. Although other phenotypes were not different compared with the wild-type parent, we found that HEp-2 and T84 cells infected with the ShET-2 mutant exhibited significantly reduced IL-8 secretion into the basolateral compartment, suggesting that ShET-2 might participate in the Shigella-induced inflammation of epithelial cells. Shigella spp. are important enteric pathogens, producing an estimated 164.7 million infections worldwide per year (Kotloff et al., 1999). Shigella infections are characterized by invasion of the colonic mucosa, followed by epithelial cell inflammation and ultimately destruction.

The harvested BMDC were divided into groups and further cultured

The harvested BMDC were divided into groups and further cultured for 18 hr in medium alone as control or in the presence of rHp-CPI, LPS, CpG, LPS plus rHp-CPI or CpG plus rHp-CPI. The BMDC were stained and analysed for the expression of co-stimulatory and

MHC-II molecules. The results show that treatment of the immature DC with rHp-CPI alone reduced the expression of the MHC-II molecule but did not alter the frequencies of CD11c+ DC that express CD40, CD80 and CD86 and the expression levels of these molecules compared with medium control group (Fig. 5a,b). The immature DC stimulated with LPS showed significantly increased expression of CD40 and CD80 (both the frequencies of positive cells KU-57788 order and the MFI) compared with medium control, and rHp-CPI treatment reduced the increased CD80 expression in response to LPS stimulation, but had no effect on CD40 expression (Fig. 5a,b). CpG stimulation of the immature BMDC also induced enhanced expression of CD40 and CD80. The rHp-CPI inhibited the increased expression of CD40 and CD80 induced by CpG (Fig. 5a,b). We further examined the cytokine production by BMDC and observed that the differentiated immature

BMDC with or without rHp-CPI treatment produced minimal levels of IL-6, IL-12p40 and TNF-α. Stimulation of the immature BMDC with LPS and CpG induced increased production R428 ic50 of these pro-inflammatory cytokines. The rHp-CPI treatment reduced the IL-6 production induced by both LPS and CpG, and TNF-α production induced by CpG (Fig. 5c). These results show that although treatment of rHp-CPI alone did not alter immature BMDC co-stimulatory molecule expression and cytokine production, it modulates these activation responses of DC induced by LPS and CpG. To determine whether the T-cell activation function of DC is altered by rHp-CPI, DC and CD4+

a T-cell co-culture assay was performed. Bone marrow cells were cultured in the AZD9291 solubility dmso medium containing GM-CSF as described above. The immature BMDC were harvested on day 7, re-plated and cultured for 24 hr to obtain matured DC. Mature BMDC were incubated either in medium alone or with rHp-CPI for 2 hr and then pulsed with OVA antigen. The two groups of DC were then co-cultured with OVA-specific CD4+ T at the ratio of 1 : 2. As shown in Fig. 6(a), BMDC treated with rHp-CPI before OVA antigen pulsing induced a lower level CD4+ T-cell proliferation response than the BMDC that were pulsed with OVA only. CD4+ T cells co-cultured with BMDC that were treated with rHp-CPI and pulsed with OVA produced significantly less interferon-γ than the CD4+ T cells co-cultured with BMDC pulsed with OVA only (Fig. 6b). In this DC and CD4 T-cell co-culture, no significant levels of IL-4, IL-10 and IL-13 were detected. Adoptive transfer of BMDC was performed to further assess the effect of rHp-CPI on the function of DC. Mice were transferred with enriched BMDC that were pulsed with OVA with or without pre-treatment of rHp-CPI and boosted 4 weeks later with OVA antigen.

To date, our results provide the only evidence showing the existe

To date, our results provide the only evidence showing the existence of FEZ1 in striatum and substantia nigra of adult rat brain, an elevation of FEZ1 gene and protein levels

after 6-OHDA injection, and the cellular localization of FEZ1 in striatum and substantia nigra of both 6-OHDA-lesioned and sham-lesioned rats. Navitoclax Additionally, our data showed that FEZ1 mRNA and protein expression in striatum and substantia nigra gradually increased after injury, peaked, and then decreased. It has been previously described that FEZ1 is associated with dopaminergic neurone differentiation [30], and furthermore, another study has shown that FEZ1-deficient mice often present with abnormal behaviours resulting from altered dopamine release in the mesolimbic pathway [32]. Colocalization of FEZ1 within GFAP-positive click here or TH-positive cells demonstrated that FEZ1 was predominantly expressed by TH-positive neurones in sham-operated rats. In contrast, FEZ1 colocalized with GFAP-positive cells in PD rats, demonstrating the exclusive expression of FEZ1 in reactive astrocytes. Altogether, the preservation of FEZ1 mRNA levels in PD rats likely reflects a dynamic shift of expression from dopaminergic neurones to astrocytes during disease-associated

tissue remodelling. Sakae et al. indicated that a FEZ1 deficiency in GABAergic neurones may alter dopaminergic transmission, resulting in abnormal behaviours. They suggested that FEZ1 in GABAergic neurones might be neuroprotective [32]. In our observations,

FEZ1 levels in astrocytes increased in substantia nigra of PD rats, suggesting that astrocytic FEZ1 also plays an important role in neuroprotection. In cultured hippocampal neurones, the silencing of FEZ1 by FEZ1 siRNA inhibits axonal elongation [24]. Therefore, the loss of FEZ1 in TH-positive neurones may lead to the degeneration of dopamine Coproporphyrinogen III oxidase neurones. We supposed that injury to DA neurones might increase astrocytic FEZ1 levels in substantia nigra, knowing that the participation of reactive astrocytes in PD pathogenesis was generally assumed. Thus, we hypothesized that FEZ1 might be critical for astrocyte activation after injury. Our triple immunostaining detection of TH, GFAP and FEZ1 further confirmed our hypothesis. In addition, Western blot analysis showed that in striatum and substantia nigra after injury, there was a remarkable increase in GFAP expression levels. It is therefore possible that a direct link between FEZ1 expression and reactive astrocytes exists after injury. We examined the cortex and did not find changes in FEZ1 in neurones or astrocytes (data not shown). We believe that relocalization of FEZ1 into astrocytes might be caused by the damage to DA neurones, which induces an upregulation of FEZ1 in astrocytes. Taken together, these data indicate that a relationship exists between FEZ1 expression and reactive gliosis following 6-OHDA-induced injury.