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Background and Objectives: Current manual and automated phenotyping methods are based on visual detection of the antigen–antibody interaction. This approach has several limitations including the use of large volumes of patient and reagent red blood cells (RBCs) and antisera to produce a visually detectable reaction. We sought to determine whether the flow cytometry could be developed and validated to perform RBC phenotyping to enable a high‐throughput method of phenotyping using comparatively miniscule reagent volumes via fluorescence‐based detection of antibody binding. Materials and Methods: RBC phenotyping by flow cytometry was performed using monoclonal direct typing antisera (human IgM): anti‐C, ‐E, ‐c, ‐e, ‐K, ‐Jka, ‐Jkb and indirect typing antisera (human IgG): anti‐k, ‐Fya, ‐Fyb, ‐S, ‐s that are commercially available and currently utilized in our blood transfusion services (BTS) for agglutination‐based phenotyping assays. Results: Seventy samples were tested using both flow‐cytometry‐based‐phenotyping and a manual tube standard agglutination assay. For all the antigens tested, 100% concordance was achieved. The flow‐cytometry‐based method used minimal reagent volume (0.5–1 μl per antigen) compared with the volumes required for manual tube standard agglutination (50 μl per antigen) Conclusion: This study demonstrates the successful validation of flow‐cytometry‐based RBC phenotyping. Flow cytometry offers many benefits compared to common conventional RBC phenotyping methods including high degrees of automation, quantitative assessment with automated interpretation of results and extremely low volumes of reagents. This method could be used for high‐throughput, low‐cost phenotyping for both blood suppliers and hospital BTS. [ABSTRACT FROM AUTHOR]

Aim: An immunoproteomic approach was followed to identify immunoreactive antigens of fish ectoparasite, Argulus siamensis with rohu (Labeo rohita) immune sera for screening of potential vaccine candidates. Materials and results: The whole adult Argulus antigen was run in 2D electrophoresis with IEF in 7 cm IPG strips of pH 4‐7 and SDS‐PAGE with 12% acrylamide concentration. Two parallel gels were run; one was stained with silver stain, and the other was Western blotted to nitrocellulose paper (NCP) and reacted with rohu anti‐A siamensis sera. Fourteen protein spots corresponding to the spots developed in NCP were picked from the silver‐stained gel and subjected to mass spectrometry in MALDI‐TOF/TOF. The MS/MS spectra were analysed in MASCOT software with taxonomy 'other metazoa' and the proteins identified based on similarity with the proteins from heterologous species. The gene ontology analysis revealed a majority of proteins being involved in binding activity in 'molecular function' and belonging to metabolic processes in 'biologic process' categories. The possibility of these proteins as vaccine candidates against Asiamensis is discussed in the paper. Conclusion: Three of the identified proteins namely, bromodomain‐containing protein, anaphase‐promoting complex subunit 5 and elongation factor‐2 could possibly serve as vaccine candidates against argulosis in carps. [ABSTRACT FROM AUTHOR]