Project description:The Ras family of GTPases play an important role in signaling nodes downstream to T cell receptor and CD28 activation, potentially lowering the threshold for TCR activation by autoantigens. Somatic mutation in NRAS or KRAS may cause a rare autoimmune disorder coupled with abnormal expansion of lymphocytes. T cells from Rheumatoid Arthritis (RA) patients show excessive activation of Ras/MEK/ERK pathway. The small molecule farnesylthiosalicylic acid (FTS) interferes with the interaction between Ras GTPases and their prenyl-binding chaperones to inhibit proper plasma membrane localization. In the present study, we tested the therapeutic and immunomodulatory effects of FTS and its derivative 5-fluoro-FTS (F-FTS) in the rat adjuvant-induced arthritis model (AIA). We show that AIA severity was significantly reduced by oral FTS and F-FTS treatment compared to vehicle control treatment. FTS was as effective as the mainstay anti-rheumatic drug methotrexate, and combining the two drugs significantly increased efficacy compared to each drug alone. We also discovered that FTS therapy inhibited both the CFA-driven in vivo induction of Th17 and IL-17/IFN-g producing double positive as well as the upregulation of serum levels of the Th17-associated cytokines IL-17A and IL-22. By gene microarray analysis of effector CD4+ T cells from CFA-immunized rats, re-stimulated in vitro with the mycobacterium tuberculosis heat-shock protein 65 (Bhsp65), we determined that FTS abrogated the Bhsp65-induced transcription of a large list of genes (e.g. Il17a/f, Il22, Ifng, Csf2, Lta, and Il1a). The functional enrichment bioinformatics analysis showed significant overlap with predefined gene sets related to inflammation, immune system processes and autoimmunity. In Conclusions, FTS and F-FTS display broad immunomodulatory effects in AIA with inhibition of the Th17-type response to a dominant arthritogenic antigen. Hence, targeting Ras signal-transduction cascade is a potential novel therapeutic approach for RA.
Project description:Chronic inflammation is responsible for a number of debilitating human diseases including inflammatory bowel disease, multiple sclerosis, and rheumatoid arthritis. The Th17 subset of T lymphocytes is an important player in the development of these pathogenic conditions. The transcription factor, RORgt was initially coined the master regulator of the Th17 program, but targeting RORgt therapeutically is dangerous owing to an enhanced risk of thymoma upon its inhibition. Another ROR family member, RORa, has also been implicated in Th17 function.
Project description:Chronic inflammation is responsible for a number of debilitating human diseases including inflammatory bowel disease, multiple sclerosis, and rheumatoid arthritis. The Th17 subset of T lymphocytes is an important player in the development of these pathogenic conditions. The transcription factor, RORgt was initially coined the master regulator of the Th17 program, but targeting RORgt therapeutically is dangerous owing to an enhanced risk of thymoma upon its inhibition. Another ROR family member, RORa, has also been implicated in Th17 function.
Project description:Chronic inflammation is responsible for a number of debilitating human diseases including inflammatory bowel disease, multiple sclerosis, and rheumatoid arthritis. The Th17 subset of T lymphocytes is an important player in the development of these pathogenic conditions. The transcription factor, RORgt was initially coined the master regulator of the Th17 program, but targeting RORgt therapeutically is dangerous owing to an enhanced risk of thymoma upon its inhibition. Another ROR family member, RORa, has also been implicated in Th17 function.
Project description:Chronic inflammation is responsible for a number of debilitating human diseases including inflammatory bowel disease, multiple sclerosis, and rheumatoid arthritis. The Th17 subset of T lymphocytes is an important player in the development of these pathogenic conditions. The transcription factor, RORgt was initially coined the master regulator of the Th17 program, but targeting RORgt therapeutically is dangerous owing to an enhanced risk of thymoma upon its inhibition. Another ROR family member, RORa, has also been implicated in Th17 function.
Project description:The Norway rat has important impacts on our life. They are amongst the most used research subjects, resulting in ground-breaking advances. At the same time, wild rats live in close association with us, leading to various adverse interactions. In face of this relevance, it is surprising how little is known about their natural behaviour. While recent laboratory studies revealed their complex social skills, little is known about their social behaviour in the wild. An integration of these different scientific approaches is crucial to understand their social life, which will enable us to design more valid research paradigms, develop more effective management strategies, and to provide better welfare standards. Hence, I first summarise the literature on their natural social behaviour. Second, I provide an overview of recent developments concerning their social cognition. Third, I illustrate why an integration of these areas would be beneficial to optimise our interactions with them.
Project description:BackgroundMurine kobuviruses (MuKV) are newly recognized picornaviruses first detected in murine rodents in the USA in 2011. Little information on MuKV epidemiology in murine rodents is available. Therefore, we conducted a survey of the prevalence and genomic characteristics of rat kobuvirus in Guangdong, China.ResultsFecal samples from 223 rats (Rattus norvegicus) were collected from Guangdong and kobuviruses were detected in 12.6% (28) of samples. Phylogenetic analysis based on partial 3D and complete VP1 sequence regions showed that rat kobuvirus obtained in this study were genetically closely related to those of rat/mouse kobuvirus reported in other geographical areas. Two near full-length rat kobuvirus genomes (MM33, GZ85) were acquired and phylogenetic analysis of these revealed that they shared very high nucleotide/amino acids identity with one another (95.4%/99.4%) and a sewage-derived sequence (86.9%/93.5% and 87.5%/93.7%, respectively). Comparison with original Aichivirus A strains, such human kobuvirus, revealed amino acid identity values of approximately 80%.ConclusionOur findings indicate that rat kobuvirus have distinctive genetic characteristics from other Aichivirus A viruses. Additionally, rat kobuvirus may spread via sewage.
Project description:Inflammation is a key component of pathological angiogenesis. Here we induce cornea neovascularisation using sutures placed into the cornea, and sutures are removed to induce a regression phase. We used whole transcriptome microarray to monitor gene expression profies of several genes
Project description:Ecological factors, such as predation, have traditionally been used to explain sociability. However, it is increasingly recognised that individuals within a group do not associate randomly, and that these non-random associations can generate fitness advantages. The majority of the empirical evidence on differentiated associations in group-living mammals, however, comes from a limited number of taxa and we still know very little about their occurrence and characteristics in some highly social species, such as rats (Rattus spp.). Here, using network analysis, we quantified association patterns in four groups of male fancy rats. We found that the associations between rats were not randomly distributed and that most individuals had significantly more preferred/avoided associates than expected by random. We also found that these preferences can be stable over time, and that they were not influenced by individuals' rank position in the dominance hierarchy. Our findings are consistent with work in other mammals, but contrast with the limited evidence available for other rat strains. While further studies in groups with different demographic composition are warranted to confirm our findings, the occurrence of differentiated associations in all male groups of rats have important implications for the management and welfare of captive rat populations.