Investigation of platelet-antibody interactions using ultrasound-induced chemiluminescence.

Abstract

Background: Platelet transfusion refractoriness (PTR) presents a significant clinical challenge, often requiring specialized diagnostic and donor-matching strategies. Existing immunoassays detect anti-platelet antibodies but do not assess their functional impact.

Objective: This study aimed to evaluate the feasibility of using ultrasound-induced chemiluminescence (UICL) as a functional assay to detect interactions between platelet concentrates (PCs) and selected antibodies (anti-HLA and ABO antibodies).

Methods: Native and antibody-exposed PCs were analyzed using luminol-based chemiluminescence following high-frequency ultrasound stimulation. The signal intensity, reflecting reactive oxygen species production, was measured and standardized using an activation index. Microscopic, cytometric, and hematologic assessments were performed to validate platelet activation.

Results: Native PCs present low spontaneous chemiluminescence, which increase approximately tenfold upon ultrasound stimulation. The presence of anti-platelet antibodies additionally enhances the chemiluminescence signal following ultrasound activation. Using a quantitative activation index allows for comparison of platelet-antibody interactions and differentiation of compatible versus incompatible PCs. The lower the activation index, the better the antigenic match between the donor platelets and the patient's immune system. The method correlates with conventional HLA matching techniques (e.g., flow cytometry) and may support the selection of compatible PCs for alloimmunized patients. Morphological and volumetric changes confirm platelet activation post-sonication.

Conclusion: UICL is a rapid, sensitive, and functionally informative method for assessing platelet-antibody interactions. It holds promise as a complementary or alternative approach to traditional immunologic testing in the management of immune-mediated PTR and may enhance transfusion decision-making, especially in settings where immunogenetic data are limited or time-sensitive.