S103Abstracts

lesions on MRI scans. Although these MRI studies suggest thebreakdown of the blood-brain barrier (BBB) as an importantfeature in MS pathogenesis, limited information is availableon the pathological changes occurring at the BBB duringlesion genesis. Thus, this study was focused to characterizethe differential changes of BBB components, particularly atthe early stages of lesion formation. MS lesions werecategorized as nascent, active, chronic active and chronicinactive. Sections were immunostained for distinct leuko-cyte markers and BBB disruption was determined byevaluating the expression pattern of fibrinogen, laminin,GFAP and the junctional proteins occludin, claudin-5, ZO1,VE-cadherin, α-catenin and p120-catenin. In addition, tocorrelate BBB disruption and endothelial activation, theexpression of ICAM-1, VCAM-1 and ALCAM was studied.Nascent lesions displayed moderate leukocyte infiltration,very limited demyelination, moderate gliosis, discretebasement membrane abnormalities, considerable changesin the expression of junctional proteins and increasedexpression of adhesion molecules. BBB junctional proteinsand basement membrane components were more severelydisrupted in active lesions and the expression pattern of mostjunctional components was partially reestablished in chronicactive and inactive lesions. Our pathological findingsindicate the presence of early disturbances in junctional,cell adhesion and basement membrane proteins at the BBBlevel in non-demyelinating MS specimens. These earlyvascular changes coincide with perivascular leukocyteinfiltration and bring pathological support for importantBBB disruption in the initial stages of MS lesion formation.

doi:10.1016/j.clim.2010.03.308

F.87. Sublingual Desensitization or ImmuneModulation with Dialyzable Leucoyte ExtractsImproves theClinicalOutcome inAllergic ConjunctivitisMaria Carmen Jimenez-Martinez2, Gustavo Aguilar1,Concepcion Santacruz1, Atzin Robles-Contreras1, Julio Ayala1,Pedro Hernandez4, Raul Chavez2, Sergio Estrada–Parra3, MayraPerez–Tapia3. 1Institute of Ophthalmology, Mexico City,Mexico; 2UNAM, Mexico City, Mexico; 3National School ofBiological Sciences, Laboratory of Molecular Immunology-II,Mexico City, Mexico; 4National Autonomous University ofMexico, Mexico City, Mexico

Purpose: To evaluate the clinical outcome(CO), and tear-cytokines(TC), before and after 6 m of Sublingual immu-notherapy(SLIT) or Dialyzable Leukocyte Extracts(DLE) inOcular Allergy(OA). Methods: Patients were divided into 3groups according to allergen skin reactivity (ASR). Group A(GA) were ASR+ patients treated with SLIT; Group B(GB) wereASR+ patients treated with DLE; Group C(GC) were ASR-patients treated with DLE. Ophthalmologic data wereassessed by developing an analogue-visual table. Tearssamples were collected to determine Th1/Th2 cytokines bycytometric arrays. CO and TC were evaluated beforetreatment (T0), and after 3 m and 6 m. Statistical analysiswas performed with ANOVA test. Reuslts: TC results: IL-2GAT0 6.2 pg/mL, 6 m 3.8 pg/mL; IL-2 GBT0 4.1 pg/mL, 6 m

3.4 pg/mL; IL-2 GCT0 4.6 pg/mL, 6 m 1.8 pg/mL; IL-4 GAT07.8 pg/ml, 6 m 5.1 pg/mL; IL-4 GBT0 3.5 pg/mL, 6 m 4.7 pg/mL; IL-4 GCT0 9.4 pg/ml, 6 m 2.6 pg/mL; IL-5 GAT0 3.9 pg/mL, 6 m 2.8 pg/mL, GBT0 4.3 pg/mL, 6 m 3.3 pg/mL; GCT07.6 pg/mL, 6 m 2.9 pg/mL; IL-10 GAT0 6.9 pg/mL, 6 m5.7 pg/mL, GBT0 5 pg/mL, 6 m 10.7 pg/mL; GCT0 9.5 pg/mL, 6 m 3.7 pg/mL; IFN-g GAT0 10.7 pg/mL, 6 m 5.5 pg/mL,GBT0 8.5 pg/mL, 6 m 6.7 pg/mL, GCT0 15.1 pg/mL, 6 m notdetected; TNFGAT0 3.8 pg/mL, 6 m 4.9 pg/mL, GBT0 3.7 pg/mL, 6 m 3.6 pg/mL, GCT0 6.2 pg/mL, 6 m 2.7 pg/mL. COResults: Clinical improve was observed in 60% of GApatients,33% of GCpatients and 14% of GBpatients. Conclusions: SLITwith the triggering Ag was the best treatment to OApatientsand ASR; DLE was the best option to OApatients without ASR.We did not find statistical correlations between the CO andTC. It is possible the involvement of other regulatorycytokines in the clinical improvement of patients. Acknowl-edgements: CONACyT 71291.

doi:10.1016/j.clim.2010.03.309

F.88. Predicting Autoimmunity FollowingTreatment of Multiple Sclerosis with AlemtuzumabJoanne Jones, Alastair Compston, Alasdair Coles. Universityof Cambridge, Cambridge, United Kingdom

The lymphocyte-depleting humanisedmonoclonal antibodyalemtuzumab is highly effective in the treatment of earlyrelapsing-remitting multiple sclerosis. However 30% ofpatients develop autoimmunity, months to years aftertreatment, usually targeting the thyroid gland and rarelyblood components. Autoimmunity arising in the context oflymphopenia is well recognised but not fully understood. Wehave hypothesised that autoimmunity occurs, not as a result oflymphopenia itself, but due to the individual's homeostaticresponse to it. In support of this we have shown thatautoimmunity arises in those patients with higher rates of Tcell cycling driven by genetically determined higher levels ofserum IL-21, detectable even prior to alemtuzumab treatment(JCI 2009). We now show that pre-treatment serum levels oftwo further homeostatic cytokines, IL-7 and CCL21, alsopredict autoimmunity following alemtuzumab; with higherserum IL-7 protecting against autoimmunity (7.5 pg/mL vs.3.4 pg/mL; pb0.001) and higher serum CCL21 associating withit (492 pg/mL vs. 432 pg/mL; pb0.001).We demonstrate how,in combination, pre-treatment serum levels of IL-21, IL-7, andCCL21, can be used to accurately model the risk of developingautoimmunitymonths to years after lymphodepletion. This hassignificant implications for counselling patients with multiplesclerosis considering treatment with alemtuzumab. Theconcept that one can predict the long-term consequences ofan immunosuppressive agent and tailor treatment accordinglyis entirely novel. This approach may offer a new way ofthinking about, and dealing with, the increasingly complexrisk-benefit analysis required in the use of biologic agents inthe treatment of multiple sclerosis.

doi:10.1016/j.clim.2010.03.310