Inflammatory stimuli induce immunoresponsive gene 1 (IRG1) expression that in turn catalyzes the production of itaconate from the tricarboxylic acid cycle. Itaconate has recently emerged as a regulator of immune cell functions, especially in macrophages. Studies show that itaconate is required for the activation of anti-inflammatory transcription factor Nrf2 by LPS in mouse and human macrophages, and LPS-activated IRG1-/- macrophages that lack endogenous itaconate production exhibit augmented inflammatory responses. Moreover, dimethyl itaconate (DMI), an itaconate derivative, inhibits IL-17-induced IκBς activation in keratinocytes and modulates IL-17-IκBς pathway-mediated skin inflammation in an animal model of psoriasis. Currently, the effect of itaconate on regulating macrophage functions and peripheral inflammatory immune responses is well established. However, its effect on microglia (MG) and CNS inflammatory immune responses remains unexplored. Thus, we investigated whether itaconate possesses an immunomodulatory effect on regulating MG activation and CNS inflammation in animal models of multiple sclerosis, experimental autoimmune encephalomyelitis (EAE). Chronic C57BL/6 EAE was induced followed by DMI treatment. The effect of DMI on disease severity, blood-brain barrier (BBB) disruption, MG activation, peripheral Th1/Th17 differentiation, and the CNS infiltration of Th1/Th17 cells in EAE was determined. Primary MG was cultured to study the effect of DMI on MG activation. Relapsing-remitting SJL/J EAE was induced to assess the therapeutic effect of DMI. Our results show DMI ameliorated disease severity in the chronic C57BL/6 EAE model. Further analysis of the cellular and molecular mechanisms revealed that DMI mitigated BBB disruption, inhibited MMP3/MMP9 production, suppressed microglia activation, inhibited peripheral Th1/Th17 differentiation, and repressed the CNS infiltration of Th1 and Th17 cells. Strikingly, DMI also exhibited a therapeutic effect on alleviating severity of relapse in the relapsing-remitting SJL/J EAE model. We demonstrate that DMI suppresses neuroinflammation and ameliorates disease severity in EAE through multiple cellular and molecular mechanisms, suggesting that DMI can be developed as a novel therapeutic agent for the treatment of MS/EAE through its immunomodulatory and anti-inflammatory properties.
Impaired mucociliary motility enhances antigen-specific nasal IgA immune responses to a cholera toxin-based nasal vaccine
The buffer was exchanged with PBS and the concentration of purified protein was measured by using a BCA protein assay kit. The FITC-PspA was stored at −80°C until future use. CT was purchased from List Biological Laboratories, Inc. (Campbell, CA, USA)
Then, the above emulsions were subcutaneously injected (Day 1). Pertussis toxin (PTX; List Biological Labs, Campbell, CA) (300 ng) was intraperitoneally administered on the rst and third days post-immunization. Bixin Treatment
Abstract Background Multiple sclerosis (MS), an autoimmune and degenerative disease, is characterized by demyelination and chronic neuroinflammation.Bixin is a carotenoid isolated from the seeds of Bixa orellana that exhibits various potent pharmacological activities, including antioxidant, anti-inflammation, and anti-tumor. However, the effects of bixin on MS remain elusive.Methods To evaluate the effects and underlying molecular mechanisms of bixin on MS, experimental autoimmune encephalomyelitis (EAE) was established in C57BL/6 mice, which were treated with intragastric administration of bixin solutions. To evaluate the molecular mechanisms of bixin, quantitative reverse-transcription PCR, western blot, immunohistochemistry, and enzyme-linked immunosorbent assay analyses were performed.Results We found that bixin significantly improved the symptoms in EAE mice, and suppressed microglia aggregation and TXNIP/NLRP3 inflammasome activity by scavenging excessive reactive oxygen species (ROS). Furthermore, bixin activated nuclear factor erythroid 2-related factor 2 (Nrf2) and its downstream genes in EAE mice, and these effects were suppressed upon inhibiting Nrf2 expression with the Nrf2 inhibitor ML385.Conclusions Bixin prevented neuroinflammation and demyelination in EAE mice mainly by scavenging ROS through activation of the Nrf2 signaling pathway. Taken together, our results indicate that bixin is a promising therapeutic candidate to treat MS.
Serum albumin-binding VH Hs with variable pH sensitivities enable tailored half-life extension of biologics
CA). Full-length Clostridium difficile toxin A (Cat#152C) was purchased from List Biological (Campbell, CA) and a recombinant toxin B fragment (TcdB aa 1751-2366) was provided by Dr Kenneth Ng (University of Calgary). DNA
Then, this emulsion was injected intravenously followed by intraperitoneal injection of 300 ng pertussis toxins (List Biological Lab, USA) at the day 0 and day 2. After EAE scoring reached one (approximately 10 days after immunization), CM (100×) was administrated