A novel assay for the detection of anti-human platelet antigen antibodies (HPA-1a) based on peptide aptamer technology

Abstract

BackgroundNeonatal alloimmune thrombocytopenia is mostly due to the presence of maternal antibodies against the fetal platelet antigen HPA-1a on the platelet integrin GPIIb-IIIa. Accurate detection of anti-HPA-1a antibodies in the mother is, therefore, critical. Current diagnostic assays rely on the availability of pools of human platelets that vary according to donors and blood centers. There is still no satisfactory standardization of these assays. Design and MethodsPeptide aptamer was used to detect and identify HPA-1a-specific antibodies in human serum that do not require human platelets. A peptide aptamer library was screened using an anti-HPA1a human monoclonal antibody as a bait to isolate an aptamer that mimics the human platelet antigen HPA-1a. ResultsThis is the first report in platelet immunology of the use of a peptide aptamer for diagnostic purposes. This assay gives better results than the MAIPA currently in use, detecting around 90% of the expected alloantibodies. ConclusionsThis assay could help define a standard for the quantitation of anti-HPA antibodies. This report also demonstrates that peptide aptamers can potentially detect a variety of biomarkers in body fluids; this is of particular interest for diagnostic purposes.Key words: peptide aptamers, neonatal alloimmune thrombocytopenia, platelets, HPA-1a, diagnostic assay, MAIPA. Haematologica 2012; 97(5):696-704. doi:10.3324/haematol.2011 A novel assay for the detection of anti-human platelet antigen antibodies (HPA-1a) based on peptide aptamer technology Citation: Thibaut J, Mérieux Y, Rigal D, and Gillet G. A novel assay for the detection of anti-human platelet antigen antibodies (HPA-1a) based on peptide aptamer technology.

Development of a single-antigen magnetic bead assay (SAMBA) for the sensitive detection of HPA-1a alloantibodies using tag-engineered recombinant soluble β3 integrin

“…HPA-1a alloantibodies are responsible for various syndromes in immune-mediated thrombocytopenia. Although a wide range of assays and techniques have been established (Stafford et al, 2008;von dem Borne et al, 1978;Campbell et al, 2007;Meyer et al, 2006a,b;Bakchoul et al, 2007;Fujiwara et al, 2009;Wautier, 2000;Thibaut et al, 2012;Chong et al, 2011;Quiel et al, 2012), the MAIPA is still considered the gold standard for the detection of HPA-1a alloantibodies. However, the sensitivity of many of these assays has been questioned , and interlaboratory variation has been observed in the detection of HPA-specific alloantibodies Sachs et al, 2012).…”

“…The odyssey towards HPA-1a alloantibody detection based on immobilization of platelet antigens with monoclonal antibodies (MoAbs) in the assay known as monoclonal antibody-specific immobilization of platelet antigens assay (MAIPA) was first described by Kiefel et al (1987). Since then, dramatic efforts and progress have been made towards establishing alternative assays for HPA-1a alloantibody detection (Stafford et al, 2008;von dem Borne et al, 1978;Campbell et al, 2007;Meyer et al, 2006a,b;Bakchoul et al, 2007;Fujiwara et al, 2009;Wautier, 2000;Thibaut et al, 2012;Chong et al, 2011;Quiel et al, 2012). However, such assays are hampered by the limited availability of MoAbs and suitable platelet donors.…”

Clinical Significance of Positive Platelet Immunofluorescence Assay in Adult Immune Thrombocytopenia

“…This assay sensitivity is about 90 % and gives better results than the MAIPA method for detecting antibody in Neonatal alloimmune thrombocytopenia [19].…”

A multicenter validation of recombinant β3 integrin–coupled beads to detect human platelet antigen‐1 alloantibodies in 498 cases of fetomaternal alloimmune thrombocytopenia

“…In addition, careful selection of monoclonal antibody (MoAb) reagents is required to achieve optimal sensitivity in detecting clinically relevant HPA‐1a antibodies . As a consequence, several other assay platforms have been developed for HPA antibody detection . Recently, the Lifecodes PAKLx bead‐based assay (Immucor, Norcross, GA) became available for detecting antibodies against HPA‐1, ‐2, ‐3, ‐4, and ‐5; GPIV; and HLA Class I.…”

“…[11][12][13][14] As a consequence, several other assay platforms have been developed for HPA antibody detection. [15][16][17][18] Recently, the Lifecodes PAKLx bead-based assay (Immucor, Norcross, GA) became available for detecting antibodies against HPA-1, -2, -3, -4, and -5; GPIV; and HLA Class I. An evaluation of this assay showed comparable sensitivity and specificity with an overall concordance of 93% between MAIPA and the PAKLx assay, but only 28 FMAIT samples with HPA-1 antibodies were tested.…”