OR31 EpVIX – Innovative free software to perform epitope virtual crossmatch. Implementation and validation in a state of Brazil

• Published in: Human immunology Vol. 76; p. 27
• Main Authors: Cardoso, Raimundo Antônio, da Silva, Adalberto S, Sousa, Luiz Claudio D.M, Marroquim, Mário Sérgio C, Coelho, Antônio Gilberto B, Willcox, Glauco, Correa, Bruno M, Andrade, João Marcelo M, Lima, Antonio Vanildo S, do Monte, Semiramis J.H
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01.10.2015
• Subjects: Allergy and Immunology
• ISSN: 0198-8859; 1879-1166
• DOI: 10.1016/j.humimm.2015.07.037

Aim To achieve the highly desirable identification of lower risk donor for hypersensitized recipients is a potentially achievable issue through a fine-tuned crossmatch. We realize that the optimal way to perform such special crossmatch is to perform the antibody recognition analysis down to the HLA epitopes (eplets) level. Method development of EpViX, a user-friendly free web-based application that (1) easily runs on tablet, smartphone or computer, (2) is integrated to important free immunogenetics and population genetics resources available on the web, such as OPTN, IMGT/HLA and Epitope Registry and, (3) performs the epitope virtual crossmatch (EvXM) during the allocation process to all potential recipients with historic and actual panels. Results EpViX software implementation and validation were accomplished with kidney recipients (total of 678, 52% non-sensitized and 12% hypersensitized) from Pernambuco state, Brazil. For the validation, all the deceased donors were typed by PCR-SSO, for HLA loci - A, - B, - C, - DRB1345, - DQA, - DQB and - DPA, - DPB. During the 11 month-validation period, 91 deceased donations, 4867 EvXM and 771 CDC occurred. In this period, the maximum time elapsed between kidney capture and allocation was 10 h. EpViX showed to be accurate (94%), sensitive (91%), specific (95%), with high positive (89%) and negative (96%) prediction values. Compared to CDC the total number of discordance was 6% (2.8% FN and 3.2% FP). Interestingly, our results showed that 5% of the recipients that would be unacceptable for transplant based on CDC test are in fact acceptable when evaluated through the fine-tuning EpViX analysis. Besides, using EpViX, we found low-immunological risk donor or acceptable DSA for 45% of hypersensitized recipients. In conclusion, we successfully developed the EpViX software that helps people to work collaboratively during the transplantation process of one solid organ and performs the epitope virtual crossmatch, thus saving time. This new tool accelerates the process of organ allocation and multiplies the chances that a hypersensitized recipient has in finding a low-immunological risk donor.