Abstract
Abstract 2106
Poster Board II-83
Background Phenotyping blood donors for human platelet antigens (HPAs) can be limited by the availability of antibodies and methodologies. Robotic high throughput multiplex polymerase chain reaction (PCR) single-nucleotide polymorphism (SNP) technology provides the opportunity to perform mass genotyping for HPAs to screen apheresis donors who are negative for antigens implicated in alloimmune thrombocytopenia. This technology needs to be validated by standard polymerase chain reaction-SSP to establish a repository of platelet donors to allow for timely and adequate platelet support for patients requiring HPA-matched platelets. The objective of this study is to validate the use of high throughput SNP technology. Methods This is a prospective cohort study of 750 regular apheresis donors. Platelet apheresis donors were identified from Canadian Blood Services' Toronto Centre and genotyped for HPA 1-5 and 15 using high throughput SNP (SNPStream®) technology. HPAs were genotyped using both the sense and antisense DNA strands of each polymorphism to ensure maximum specificity. The genotypes identified by SNP were confirmed by standard methods thus all donors found to be negative for antigens implicated in alloimmune thrombocytopenia were retested using manual (sequence specific SSP-PCR at Canadian Blood Services' Platelet Immunology Laboratory and at the Toronto Centre. Results Of the 750 donors that were screened, 130 donors were found to be negative for antigens implicated in alloimmune thrombocytopenia based on SNP technology. The table illustrates genotyping results using SNP technology and SSP-PCR confirmation to date. In some instances, donors were homozygous for two low frequency HPA genotypes: 2 donors were homozygous for both HPA-1b/b and -2b/b, 6 donors for HPA-1b/b and -3b/b, 1 donor for HPA-2b/b and -3b/b, 1 donor for HPA-1b/b and -5b/b, 10 donors for HPA-1b/b and -15b/b, 4 donors for HPA-5b/b and -15b/b and 1 donor for HPA-2b/b and 15-b/b.
| HPA System . | Number of Genotypes Identified by SNP Technology . | Discrepant results Identified by SSP . |
|---|---|---|
| HPA-1 b/b | 15 | 2 (13%) |
| HPA-2 b/b | 8 | 3 (27%) |
| HPA-3 b/b | 25 | 1 (4%) |
| HPA-5 b/b | 1 | 0 |
| HPA-15 b/b | 9 | 1 (11%) |
| HPA System . | Number of Genotypes Identified by SNP Technology . | Discrepant results Identified by SSP . |
|---|---|---|
| HPA-1 b/b | 15 | 2 (13%) |
| HPA-2 b/b | 8 | 3 (27%) |
| HPA-3 b/b | 25 | 1 (4%) |
| HPA-5 b/b | 1 | 0 |
| HPA-15 b/b | 9 | 1 (11%) |
Robotic high throughput multiplex PCR SNP is potentially useful for mass genotyping of apheresis platelet donors and can identify both low frequency antigen-negative donors and combinations of these genotypes. This technology needs to be further developed.
No relevant conflicts of interest to declare.
Author notes
Asterisk with author names denotes non-ASH members.
