COMPARING TWO DIFFERENTS KITS: LABSCREEN MIXED (ONE LAMBDA) AND LIFESCREEN LIFECODES DELUXE (GENEPROBE) CLASS I AND CLASS II ANTIBODIES

"Background. Through the years, Human Leucocyte Antigen (HLA) antibodies detection has been enhanced with higher sensitivity techniques on solid phase assay (Luminex) that joined the traditional Complement Dependent Citotoxicity (CDC). HLA antibodies are relevant in patients awaiting solid organ transplantation and for the successful outcome of transplantation.. Aims. LABScreen Mixed (LSM12-One Lambda; Lagitre, IT) and Lifescreen LIFECODES Deluxe (LMX-Geneprobe; GTI, IT) are solid-phase testing platforms used for HLA antibodies both Class I and Class II detection . In this study, the sensitivities of the LABScreen Mixed product was directly compared to the Lifescreen LIFECODES Deluxe.. Methods. This study was carried out on 250 sera with or without sensitization events from patients undergoing kidney or heart transplantation, historically known to be for HLA antibodies positive or negative in CDC, ELISA assays or\/and Luminex technology. The same aliquot of each patient serum was tested, at the same time, with both kits. The two analyzed tests allow both anti-IgG antibodies detecting and the same HLA antigenic specificities relieving, except for the MICA which is present only in the LABScreen kit. We performed assays and software analysis according to the manufacturer’s instructions and criteria, with LSM12 involving the use of undiluted samples whereas LMX uses a 1:4 serum dilution.. Results. Analysis of all sera for Class I and Class II antibodies HLA showed negative results in 180\/250 (72%) and 172\/250 (69%) cases, by LABScreen and LIFECODES respectively, with a concordance of negativity in 148\/180 (82%) sera; 24\/250 (9.6%) sera were screened positively by LABScreen and 19\/250 (7.6%) by LIFECODES in both classes, with a concordance of positivity in 16 samples. Moreover, for Class I antibodies LMX was positive in 4 samples where LSM12 was negative and it was negative in 32 samples which were positive with LSM12; for Class II antibodies, we also found 8 negative samples by LMX but positive by LSM12 and 30 positive samples by LMX and negative by LSM12.. Conclusions. These preliminary data demonstrate a significant difference for both Class I and Class II antibodies. We establish that no major difference exists between the methods used in the present study. However, it is necessary to extend this study with additional tests for a better evaluation of definitive results.. . "