Shoichi Inaba

Efficacy of donor screening for HTLV-I and the natural history of transfusion-transmitted infection

BACKGROUND: It has been 10 years since the implementation in Japan of donor blood screening for human T‐cell lymphotropic virus type I (HTLV‐I). This report reviews the effectiveness of screening in preventing transmission of HTLV‐I through blood transfusion and the current status of patients with confirmed seroconversion due to transfusions given before the implementation of screening.

Mutations of the KLF1 gene detected in Japanese with the In(Lu) phenotype

In(Lu) is characterized by a reduced expression of antigens in the Lutheran blood group system as well as other blood group antigens. Mutations of the erythroid transcription factor, KLF1, have been reported to cause the In(Lu) phenotype, and we investigated Japanese In(Lu) to estimate the prevalence of the phenotype and KLF1 polymorphism.

Silent KEL alleles identified from Japanese individuals with the Ko phenotype

The rare Ko phenotype lacks all 36 antigens in the Kell blood system. The molecular basis of the Ko phenotype has been investigated, and more than 40 silent KEL alleles are reported by many investigators. The majority of silent alleles are the KEL*02 background. Here, we report molecular genetic analysis of the KEL gene in Japanese individuals with the Ko phenotype.

Fatal warm autoimmune hemolytic anemia in a child due to IgM-type autoantibodies

Herein is described a case of immunoglobulin M (IgM) warm autoimmune hemolytic anemia (AIHA) in a child who consequently died within 3 days of clinical onset. A previously healthy 11‐year‐old boy presented with fever, anemia, jaundice, and deteriorating consciousness. On direct agglutination test against group O red blood cells, agglutination was seen even at 37°C in saline, which was abolished on dithiothreitol treatment of the serum, indicating that the responsible autoantibody was IgM and had a warm‐reactive capacity. A diagnosis of IgM warm AIHA was therefore made. Hemagglutination in the visceral capillaries was considered as the direct cause of organ dysfunction. The patient died due to respiratory failure. IgM warm AIHA is a very severe condition that is difficult to reverse in an advanced state. Both prompt, definite diagnosis and intervention are therefore vital to prevent severe multi‐organ dysfunction in cases of IgM warm AIHA.

Numerical Aanalysis of a Leuko-Reducing Bowl for Intermittent Plateletpheresis System

Platelet therapy remains one of the most effective treatments. The use of WBC-depleted platelet is now mandatory to prevent a variety of adverse effects caused by transfused WBC (white blood cell) contaminating platelet. One of the current centrifuge bowls, which has most advantage for donors, has to use a WBC-depletion filter to meet the standards of WBC contamination. Development of new centrifuge bowls is intended here with the aid of CFD to guide the design of better performances. The simulation is in two stages; the first is to elucidate the mechanism of WBC-contamination of the current bowl (trajectory of WBC, based on velocity field established), and the second is to simulate the performance of new bowls on reducing remaining WBC in platelet concentrate. Evaluation of new bowls with human blood is reported.Copyright