Sophie DESPLAT-JEGO, France
Aix Marseille Université/ AP-HM and AP-HM INP, Institut de Neurophysiopathologie / Service d'immunologie Conception hospitalPresenter of 3 Presentations
PREVALENCE AND KINETICS OF ANTI-INFLIXIMAB ANTIBODIES DURING INFLIXIMAB THERAPY
Abstract
Background and Aims
Background and aims: Infliximab (IFX) is a monoclonal therapeutic anti-TNF antibody with proven efficiency in chronic inflammatory diseases. However, a significant number of patients have no primary response or lose response becoming secondary non-responders. The production of anti-drug antibodies (ADAb) increasing IFX serum clearance has been identified as a possible explanation. However the prevalence and kinetics of ADAb are not well described. Our aim was to evaluate the occurrence of ADAb in a large cohort of infliximab-treated patients.
Methods
Method: A cohort of 817 serum samples sent to our lab between 2016 and 2019 for concomitant evaluation of infliximabemia and ADAb (Lisa-Tracker, Théradiag, France) was retrospectively studied.
Results
Results: In our cohort, 91 out of 817 samples (11.13 %) were found positive for ADAb. Among them, 53 samples (58.2 %) displayed a concentration of ADAb superior to 200 µg/ml. The 91 positive samples corresponded to 71 patients and we had a longitudinal follow-up for 14 patients. Among these later, 11 patients had a stable level of ADAb during several months (>200 µg/ml for 9 patients) while we observed a modulation of ADAb levels in the 3 other ones (down-modulation in 2 cases and up-modulation in one case).
Conclusions
Conclusions: We showed here that the prevalence of ADAb during infliximab therapy is quite elevated (11, 13 %). Moreover, in our study, the ADAb levels are mainly high and seem stable. However in a minority of patients we could observe a modulation of ADAb levels during the infliximab therapy.
SERUM LEVELS OF SOLUBLE TWEAK ARE SIGNIFICANTLY ELEVATED DURING MULTIPLE SCLEROSIS.
Abstract
Background and Aims
Background and aims: TWEAK (TNF weak inducer of apoptosis) is a cytokine member of the TNF ligand superfamily. We have been the first to show that TWEAK produced by infiltrating monocytes/macrophages contributed to neuroinflammation during multiple sclerosis (MS). Moreover, we have also recently suggested on a small cohort of patients that soluble TWEAK levels were elevated in MS and were associated with disease activity. Here, our aims were to determine soluble TWEAK levels in a larger cohort of MS and to compare TWEAK levels in i) MS patients versus controls and ii) relapsing remitting MS (RRMS) patients vs progressive MS patients.
Methods
Methods: Serum samples from 200 patients with MS and controls were collected, and soluble TWEAK levels were evaluated by using a commercially available ELISA kit. The data of the first 103 MS patients and 20 controls are presented here.
Results
Results: Serum soluble TWEAK levels were significantly higher in MS patients than in controls (1031+/-388pg/ml, vs 864+/-209 pg/ml, p=0.048). Although soluble TWEAK levels were higher in RRMS patients (1071+/-441pg/ml) than in progressive MS patients (972+/-267pg/ml), this did not reach statistical significance. In the RRMS patients’ group, soluble TWEAK did not correlate with EDSS disability score (R=0.03, p=0.76).
Conclusions
Conclusions: We confirm here in an independent cohort that serum levels of TWEAK are higher in MS patients than in controls. Moreover, soluble TWEAK levels tend to be lower in progressive MS than in RRMS. Further studies examining clinical and MRI parameters (notably gadolinium enhancement) in our whole cohort are in progress.
IDS-ISYS MULTI-DISCIPLINE AUTOMATED SYSTEM IS A SIMPLE AND RELIABLE TOOL FOR CELIAC DISEASE DIAGNOSIS
Abstract
Background and Aims
Background and aims: The IDS-iSYS multi-discipline system is a compact fully automated instrument based on chemiluminescence technology. It is designed for unitary tests with ready-to-use reagent cartridges issued from a panel in the field of endocrinology, infectious diseases and autoimmunity. Detection of anti-tissue transglutaminase IgA (AtTG) is recognized as the best immunological serum test for celiac disease (CD) diagnosis. Our aim was to compare IDS-iSYS system and automated ELISA kit for routine detection of serum AtTG.
Methods
Methods: Serum samples from 175 patients (including 59 CD and 8 total IgA deficiencies) yet routinely evaluated for AtTG levels with the ELISA kit provided by Eurospital (Eu-tTG IgA, ref 9105, performed on a BEP III System (Siemens Healthcare Diagnostics)) and for anti-endomysium antibodies (monkey oesophagus slides from Medica) were analyzed by the IDS-iSYS system (IDS t-TG IgA, ref IS-AI1303). The repeatability and the reproducibility of the IDS test were also studied.
Results
Results: AtTG levels obtained from the two methods were similar for 171 out of 175 samples (97.7 %). Among the 4 discrepancies, clinical chart analysis was in favour of IDS-iSYS for two patients. It is worthy to note that all IgA deficiencies were detected by the IDS-iSYS. The repeatability of IDS AtTG test was very good and its reproducibility was good.
Conclusions
Conclusions: We show here that IDS-iSYS multi-discipline automated system is a simple and reliable tool for celiac disease diagnosis. Its capacity to detect IgA deficiency during the AtTG run is of interest for a good interpretation of the test.