Tuftsin Combines With Remyelinating Therapy and Improves Outcomes in Models of CNS Demyelinating Disease

Though promoting remyelination in multiple sclerosis (MS) has emerged as a promising therapeutic strategy, it does not address inflammatory signals that continue to induce neuronal damage and inhibit effectiveness of repair mechanisms. Our lab has previously characterized the immunomodulatory tetrapeptide, tuftsin, which induces an anti-inflammatory shift in microglia and macrophages. This targeted anti-inflammatory agent improves physical deficits in experimental autoimmune encephalomyelitis (EAE), an animal model of MS. Here, we sought to determine whether tuftsin is also effective in combination with benztropine, an FDA-approved drug that stimulates remyelination, in both EAE and in the cuprizone model of demyelination. We show that combining these two agents to promote anti-inflammatory and remyelinating mechanisms alleviates symptoms in EAE and lessens pathological hallmarks in both MS models. Importantly, tuftsin is required to transform the inflammatory CNS environment normally present in EAE/MS into one of an anti-inflammatory nature, and benztropine is required in the cuprizone model to improve remyelination. Our data further support tuftsin's beneficial immunomodulatory activity in the context of EAE, and show that when studying remyelination in the absence of an autoimmune insult, tuftsin still activated microglia toward an anti-inflammatory fate, but benztropine was necessary for significant repair of the damaged myelin. Overall, tuftsin effectively combined with benztropine to significantly improve MS-like pathologies in both models

Tuftsin Promotes an Anti-Inflammatory Switch and Attenuates Symptoms in Experimental Autoimmune Encephalomyelitis

Multiple sclerosis (MS) is a demyelinating autoimmune disease mediated by infiltration of T cells into the central nervous system after compromise of the blood-brain barrier. We have previously shown that administration of tuftsin, a macrophage/microglial activator, dramatically improves the clinical course of experimental autoimmune encephalomyelitis (EAE), a well-established animal model for MS. Tuftsin administration correlates with upregulation of the immunosuppressive Helper-2 Tcell (Th2) cytokine transcription factor GATA-3. We now show that tuftsin-mediated microglial activation results in shifting microglia to an anti-inflammatory phenotype. Moreover, the T cell phenotype is shifted towards immunoprotection after exposure to tuftsin-treated activated microglia; specifically, downregulation of pro-inflammatory Th1 responses is triggered in conjunction with upregulation of Th2-specific responses and expansion of immunosuppressive regulatory T cells (Tregs). Finally, tuftsin-shifted T cells, delivered into animals via adoptive transfer, reverse the pathology observed in mice with established EAE. Taken together, our findings demonstrate that tuftsin decreases the proinflammatory environment of EAE and may represent a therapeutic opportunity for treatment of MS

Models of classroom assessment for course-based research experiences

Course-based research pedagogy involves positioning students as contributors to authentic research projects as part of an engaging educational experience that promotes their learning and persistence in science. To develop a model for assessing and grading students engaged in this type of learning experience, the assessment aims and practices of a community of experienced course-based research instructors were collected and analyzed. This approach defines four aims of course-based research assessment—(1) Assessing Laboratory Work and Scientific Thinking; (2) Evaluating Mastery of Concepts, Quantitative Thinking and Skills; (3) Appraising Forms of Scientific Communication; and (4) Metacognition of Learning—along with a set of practices for each aim. These aims and practices of assessment were then integrated with previously developed models of course-based research instruction to reveal an assessment program in which instructors provide extensive feedback to support productive student engagement in research while grading those aspects of research that are necessary for the student to succeed. Assessment conducted in this way delicately balances the need to facilitate students’ ongoing research with the requirement of a final grade without undercutting the important aims of a CRE education

Microglial Function across the Spectrum of Age and Gender

Microglia constitute the resident immunocompetent cells of the central nervous system. Although much work has focused on their ability to mount an inflammatory response in reaction to pathology, recent studies have delved into their role in maintaining homeostasis in the healthy brain. It is important to note that the function of these cells is more complex than originally conceived, as there is increasing evidence that microglial responses can vary greatly among individuals. Here, this review will describe the changing behavior of microglia from development and birth through to the aged brain. Further, it is not only age that impacts the state of the neuroimmune milieu, as microglia have been shown to play a central role in the sexual differentiation of the brain. Finally, this review will discuss the implications this has for the differences in the incidence of neurodegenerative disorders between males and females, and between the young and old

The Experimental Autoimmune Encephalomyelitis Disease Course Is Modulated by Nicotine and Other Cigarette Smoke Components

<div><p>Epidemiological studies have reported that cigarette smoking increases the risk of developing multiple sclerosis (MS) and accelerates its progression. However, the molecular mechanisms underlying these effects remain unsettled. We have investigated here the effects of the nicotine and the non-nicotine components in cigarette smoke on MS using the experimental autoimmune encephalomyelitis (EAE) model, and have explored their underlying mechanism of action. Our results show that nicotine ameliorates the severity of EAE, as shown by reduced demyelination, increased body weight, and attenuated microglial activation. Nicotine administration after the development of EAE symptoms prevented further disease exacerbation, suggesting that it might be useful as an EAE/MS therapeutic. In contrast, the remaining components of cigarette smoke, delivered as cigarette smoke condensate (CSC), accelerated and increased adverse clinical symptoms during the early stages of EAE, and we identify a particular cigarette smoke compound, acrolein, as one of the potential mediators. We also show that the mechanisms underlying the opposing effects of nicotine and CSC on EAE are likely due to distinct effects on microglial viability, activation, and function.</p></div

Therapeutic administration of nicotine attenuates EAE symptoms.

<p><b>(A)</b> 14-day pumps filled with 200 mg/ml nicotine were placed in the backs of EAE mice at day 14 (***<0.001). Peak score <b>(B)</b> as well as cumulative score <b>(C)</b> from day 14 to day 28 were recorded and compared between the vehicle (n = 8) and nicotine-treated (n = 3) groups. <b>(D)</b> Weekly weights were plotted as a percentage of day 0 weights. (***p<0.001; *p<0.05)</p

Effects of nicotine and non-nicotine components of cigarette smoke on EAE severity.

<p>EAE was induced by injection of MOG_35–55 in CFA and pertussis toxin. <b>(A)</b> CSC was infused at 10 or 20 mg/ml into EAE mice starting at day 0 of EAE for 28 days, with DMSO as vehicle. <b>(B)</b> 20 mg/ml CSC was infused into the mice from 14 days prior to EAE induction through day 28, with 50% DMSO as vehicle. <b>(C)</b> Nicotine (200 mg/ml) was infused into EAE mice starting at Day 0 of EAE for 28 days, with saline as vehicle. Peak score <b>(D)</b> and cumulative score <b>(E)</b> were compared between CSC (n = 3)/nicotine (n = 6) and control mice (n = 8). (*** p<0.001; **p<0.01; *p<0.05).</p

Decreased demyelination in nicotine-treated mice during EAE.

<p><b>(A)</b> Frozen sections of spinal cords were isolated from vehicle (saline) and nicotine-treated mice at different time points during EAE. Eriochrome cyanine (EC) was used to visualize demyelination. Intact white matter (WM) is indicated by the blue staining and demyelination is revealed by diminished color. Areas of demyelination are indicated by asterisks; boxed regions are shown at higher magnification. <b>(B)</b> Demyelinated areas were measured using ImageJ and calculated based on equation listed in Methods. (n = 3–4, *p<0.05).</p

Increased demyelination in CSC-treated mice at day 14.

<p>Frozen sections of spinal cords were isolated from vehicle (saline/DMSO) and CSC-treated mice at day 14 and day 28 of EAE. Eriochrome cyanine <b>(A)</b> or fluoromyelin <b>(B)</b> was used to visualize demyelination. Areas of demyelination are indicated by diminished fluorescence; boxed regions are shown at higher magnification. <b>(C)</b> Demyelinated areas from <b>(B)</b> were measured using ImageJ and calculated based on equation listed in Methods (n = 4, *p<0.05). The levels of demyelination at day 14 in saline- or nicotine-infused spinal cords are also shown for comparison.</p