Academic Journal

Assessing the reliability of the PAK-LX HLA Class I bead in platelet transfusion compatibility testing.

Λεπτομέρειες βιβλιογραφικής εγγραφής
Τίτλος: Assessing the reliability of the PAK-LX HLA Class I bead in platelet transfusion compatibility testing.
Συγγραφείς: Enten H; American National Red Cross, USA., Liacini A; American National Red Cross, USA., Janes D; American National Red Cross, USA., Stedem R; American National Red Cross, USA., Gaule L; Atrium Health, USA., Berka N; American National Red Cross, USA. Electronic address: Noureddine.berka@redcross.org.
Πηγή: Human immunology [Hum Immunol] 2026 May; Vol. 87 (5), pp. 111711. Date of Electronic Publication: 2026 Mar 13.
Τύπος έκδοσης: Journal Article
Γλώσσα: English
Στοιχεία περιοδικού: Publisher: Elsevier/North-Holland Country of Publication: United States NLM ID: 8010936 Publication Model: Print-Electronic Cited Medium: Internet ISSN: 1879-1166 (Electronic) Linking ISSN: 01988859 NLM ISO Abbreviation: Hum Immunol Subsets: MEDLINE
Imprint Name(s): Original Publication: [New York] Elsevier/North-Holland.
Ιατρικοί όροι (MeSH): Isoantibodies*/blood , Histocompatibility Antigens Class I*/immunology , Histocompatibility Testing*/methods , Blood Platelets*/immunology , Platelet Transfusion*, Humans ; Female ; Reproducibility of Results ; Male ; Adult ; Middle Aged
Περίληψη: Purpose: PAK-LX, a Luminex-based assay for detecting platelet-specific glycoproteins and HLA class I antibodies, has shown limited reliability for HLA immunization. A prior study reported a 37% discrepancy compared to the single antigen bead (SAB) assay. The current study expands the cohort size to further investigate this discrepancy and uncover patterns that may explain the divergence.
Methods: A total of 137 individuals from two American Red Cross Histocompatibility laboratories (Charlotte, NC and Portland, OR) were screened using both PAK-LX (Werfen, Inc) and SAB (ThermoFisher, Inc). Data included demographics, antibody positivity, discordance rates, mean fluorescence intensity (MFI), and calculated panel reactive antibody (cPRA).
Results: SAB detected HLA class I antibodies in 73% of participants; 36% showed discordance, with 98% being PAK-LX false negatives. Mean cPRA among discordant cases was 29% (range: 2-96%). Missed antibodies had MFIs typically below 6,000 but ranged from 2,000 to 19,000.
Conclusion: PAK-LX demonstrates reduced sensitivity for the detection of HLA class I antibodies compared with single-antigen bead (SAB) assays and may fail to identify HLA alloantibodies implicated in immune-mediated platelet transfusion refractoriness. Accordingly, PAK-LX should not be used as a standalone screening assay, and confirmatory testing with SAB is recommended when immune-mediated platelet refractoriness is suspected.
(Copyright © 2026 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.)
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
Contributed Indexing: Keywords: Alloimmunization; Human leukocyte antigens; Platelet refractoriness
Substance Nomenclature: 0 (Isoantibodies)
0 (Histocompatibility Antigens Class I)
Entry Date(s): Date Created: 20260313 Date Completed: 20260710 Latest Revision: 20260710
Update Code: 20260711
DOI: 10.1016/j.humimm.2026.111711
PMID: 41825092
Βάση Δεδομένων: MEDLINE