Recent evidence suggests that HLA-A,B antigens present on human platelets, are acquired from plasma. Using hypertonic acid chloroquine (200 mg/ml, pH 5.0, 1 hr, 4 degrees C), we demonstrate elution of most or all HLA-A2 and HLA-B7,40 immunoreactive material from platelets. Corresponding antigens on human lymphocytes were not affected by this treatment. These findings are consistent with the hyp...

A 38-year-old woman (JT) was diagnosed with posttransfusion purpura and significant posthysterectomy vaginal bleeding 9 days after the transfusion of 2 U of packed red blood cells. Analysis of JT's serum by a monoclonal antibody-antigen capture enzyme-linked immunosorbent assay method showed the presence of anti-HPA-5b (anti-Bra) antibodies directed against an epitope on platelet glycoprotein (...

BACKGROUND The HPA-1 alloimmune system carried by the platelet integrin αIIbβ3 is the primary cause of alloimmune thrombocytopenia in Caucasians and the HPA-1b allele might be a risk factor for thrombosis. HPA-1a and -1b alleles are defined by a leucine and a proline, respectively, at position 33 in the β3 subunit. Although the structure of αIIbβ3 is available, little is known about structural ...

Amino acid substitutions in platelet membrane glycoproteins result in alloantigens. Identifying these polymorphisms is important in alloimmune-mediated platelet disorders. Immunophenotyping platelet antigens can be limited by the unavailability of specific antisera. The goal of this work was to identify human platelet antigen genotypes in individuals using a technique that would circumvent the ...

BACKGROUND Platelet adhesion and subsequent thrombus formation on a subendothelial matrix at the site of vascular damage play a crucial role in the arrest of posttraumatic bleeding but also in different pathological thrombotic events, such as acute coronary syndrome and stroke. Recently published studies have clearly demonstrated that platelet integri alphaIIbbeta3 is intimately involved in the...

count (mean increments: 68 109/L and 87 109/L at day 0 and day 1, respectively), but this was significantly and consistently less over the lifespan of the transfused platelets than the mean increment seen with AC-Tx (116 109/L and 146 109/L on days 0 and 1, respectively). More importantly, the survival of the random platelets was only approximately half that of antigen-compatible platelets (T1/...

OBJECTIVE To look for any possible coexistence of CACNA1A, ATP1A2, and KCNN3 gene mutations in migraine patients who had human platelet HPA-1a/1b polymorphism, which is also known as PlA1/A2 polymorphism. METHODS The study was carried out at the Neurology Clinic, Hospital University Sains Malaysia, Kelantan, Malaysia between April 2004 and March 2005. The DNA from 4 patients who had migraine ...