Organ procurement and transplantation network/united network for organ sharing histocompatibility committee collaborative study to evaluate prediction of crossmatch results in highly sensitized patients.
BACKGROUND
The requirement for a prospective crossmatch limits some organ allocation to local areas. The delay necessitated by the crossmatch restricts the distance across which offers can be made without unduly increasing the ischemia time. A collaborative study involving 14 transplant centers was undertaken by the Organ Procurement and Transplantation Network/United Network for Organ Sharing (OPTN/UNOS) Histocompatibility Committee to evaluate the accuracy with which the detection of unacceptable human leukocyte antigen (HLA) antigens by most advanced solid phase immunoassays can predict crossmatch results. In addition, using actual patients' unacceptable HLA antigens, the number of compatible donors that would have been available from the OPTN deceased kidney donors during 2002 to 2004 were investigated.


METHODS
Panel reactive antibodies were performed by conventional or solid phase assays, and crossmatches were performed by cytotoxicity or flow cytometry. Analyses were stratified for T and B cell and by method of identifying unacceptable HLA antigens and crossmatch techniques.


RESULTS
Combination of solid phase immunoassays and flow cytometry crossmatches resulted in a higher prediction rates of positive T cell (86.1%-93.5%) and B-cell crossmatches (91%-97.8%). Prediction of negative crossmatches based on different combination of panel reactive antibodies and crossmatch techniques varied from 14.3% to 57.1%. Furthermore, numerous potential compatible donors were identified for each patient, regardless of their ethnicity, in the OPTN database, when predicted incompatible ones were excluded.


CONCLUSIONS
The above results showed that with the advent of solid phase immunoassays, HLA antibodies can now be accurately detected resulting in prediction of crossmatch outcome. This should facilitate organ allocation and prevents shipment of organs to distant incompatible recipients.
Nikaein
Afzal
A
OPTN/UNOS Histocompatibility Committee, Richmond, VA, USA. Afzal.nikaein@hcahealthcare.com
Cherikh
Wida
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Nelson
Karen
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Baker
Timothy
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Leffell
Sue
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Bow
Laurine
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Crowe
Debbie
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Connick
Ketra
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Head
Mary Ann
MA
Kamoun
Malek
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Kimball
Pam
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Klohe
Ellen
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Noreen
Harriet
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Rebellato
Lorita
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Sell
Tom
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Sullivan
Karen
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Land
Geoffrey
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D001402:B-Lymphocytes / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D005434:Flow Cytometry; D006680:HLA Antigens / Q000276:immunology; D006648:Histocompatibility / Q000276:immunology; D006650:Histocompatibility Testing / Q000379:methods*; D006801:Humans; D007518:Isoantibodies / Q000097:blood; D011237:Predictive Value of Tests; D013601:T-Lymphocytes / Q000276:immunology*; D014019:Tissue Donors / Q000706:statistics & numerical data*; D009927:Tissue and Organ Procurement / Q000379:methods* / Q000706:statistics & numerical data
D006680:HLA Antigens; D007518:Isoantibodies