Page - 21 - in Advances in Neuroimmunology

BrainSci. 2016,6, 15 Forclinicalevaluationsandbodyweightchanges,weusedthegeneral linearmodel (GzLM)for repeatedmeasures, thegeneralizedestimatedequations test (GEE),withgenotype (floxedvs.Ast-IL-6 KOmice)andsexasthemainfactors. Thepost-hocStudent t-testor theMann–WhitneyU-testwasused to identify significantdifferencesbetweenAst-IL-6KOandfloxedanimalsat specific timeperiods. For theremainingvariablesanalyzed, two-wayANOVA(withgenotypeandsexas themainfactors) orGzLMwasusedforeachsexseparately followedbypost-hoc testswhenappropriate. 3.Results 3.1. LackofAstrocytic IL-6Alters theClinicalCourseofEAEinAst-IL-6KOMiceandAmelioratesEAE Symptomatology inaSex-DependentManner Both genotypes showed the prototypical ascending paralysis course with body weight loss (Figure1). TheclinicalscoreandthebodyweightchangesobservedfollowingMOG35–55 immunization upto20dpi in theAst-IL6KOandfloxedmiceareshowninFigure1.Ast-IL6KOfemalesshowed asignificantlyreducedclinical scoreandincreasedbodyweightwithrespect to femalefloxedmice, agenotypicdifferencethatwasnotobservedinthemalemice.Averageincidenceofthediseaseranged from90%to100%,andtherewerenosignificantdifferences inmortalityrate (Table2). Figure 1. Clinical course of EAE, in both floxed (n = 18 males, 28 females) and Ast-IL-6 KO (n=11males, 23 females) mice up to 20 dpi. Results are the mean˘ SEM of data pooled from Experiments1–3(Days0–20dpi;Table1).‹pat least<0.05versusfloxedmiceatspecificdaysfollowing apost-hocanalysis. 21