Tibor J. Greenwalt

The how and why of exocytic vesicles

The purpose of this review is to draw the attention of general readers to the importance of cellular exocytic vesiculation as a normal mechanism of development and subsequent adjustment to changing conditions, focusing on red cell (RBC) vesiculation. Recent studies have emphasized the possible role of these microparticles as diagnostic and investigative tools. RBCs lose membrane, both in vivo and during ex vivo storage, by the blebbing of microvesicles from the tips of echinocytic spicules. Microvesicles shed by RBCs in vivo are rapidly removed by the reticuloendothelial system. During storage, this loss of membrane contributes to the storage lesion and the accumulation of the microvesicles are believed to be thrombogenic and thus to be clinically important.

Twelve-week RBC storage

BACKGROUND: Better storage can improve RBC availability and safety. Optimizing RBC ATP production and minimizing hemolysis has allowed progressively longer storage.

The Phenotype Lu(a−b−) Together with Unconventional Kidd Groups in One Family

Minus‐minus blood group phenotypes are characterized by the absence of any detectable phenotypic representation of the alleles expected at the determining gene loci. Double minus phenotypes have been found in most blood group systems but all individuals thus far tested for the Lutheran factors have been Lu(a+b+), Lu(a+b+) or Lu(a−+). Six individuals with the hitherto undisclosed blood group Lu(a−b−) were found in three generations of a Caucasian family.

Alkaline CPD and the preservation of RBC 2,3-DPG

BACKGROUND : Concentrations of 2,3‐DPG decline rapidly in the first week of RBC storage because of the low pH of conventional storage solutions. Alkaline additive solutions, which can preserve RBCs for up to 11 weeks, still do not preserve 2,3‐DPG because the starting pH is below 7.2.

Collection of two units of leukoreduced RBCs from a single donation with a portable multiple-component collection system.

BACKGROUND: A portable automated component collection system that produces double (2) units of leukoreduced RBCs (DRBCs) from a single donation was evaluated. This study analyzed quality of the collected and final products, the efficacy of automated leukoreduction, and donor safety.

RBC storage for 11 weeks

BACKGROUND: Increasing the length of RBC storage can increase both RBC availability and quality. This work addresses 11‐week RBC storage in experimental ASs (EASs).

Blood Groups of the Thais

Blood and saliva from 456 unselected blood donors from the Siriraj Hospital, Bangkok were studied. The frequencies of the ABO and Rh groups closely resemble previous reports but A2 and Cw were seen. The high frequency of M (67.87 per cent) and the low concentration of S (8.33 per cent) make MS and NS fairly uncommon. The frequency of 14.54 per cent for P1 resembles the figure for New York Chinese. Evidence for the presence of Jk was found in three of the 15 families studied but no Jk(a—b—) phenotypes were encountered. The 30.9 per cent frequency of Le(a+b—) and the 40.05 per cent frequency of Se were unexpected, as was the presence of aberrant secretors of ABH. Others findings include 1.19 per cent Mi(a+); 0.94 per cent Mt (a+); 0.44 per cent Lu(a—b—); 1.22 per cent Ve(a‐); 2.33 per cent Di(a+) and 13.48 per cent Do(a+).

Interlaboratory comparison of red-cell ATP, 2,3-diphosphoglycerate and haemolysis measurements.

Background and Objectivesu2002 Red blood cell (RBC) storage systems are licensed based on their ability to prevent haemolysis and maintain RBC 24‐h in vivo recovery. Preclinical testing includes measurement of RBC ATP as a surrogate for recovery, 2,3‐diphosphoglycerate (DPG) as a surrogate for oxygen affinity, and free haemoglobin, which is indicative of red cell lysis. The reproducibility of RBC ATP, DPG and haemolysis measurements between centres was investigated.

The role of electrolytes and pH in RBC ASs.

BACKGROUND: Experimental additive solutions (EASs) containing saline, adenine, glucose, mannitol and disodium phosphate can support RBCs for 9 or 10 weeks if used in 200‐ or 300‐mL volumes. The effects of variations in the electrolyte composition and volume of EASs were explored.

Second Example of Anti-N in a Blood Donor of Group MN*

Anti‐N was found in the serum of a healthy blood donor of group MN. The behavior of the donors blood group antigens and the anti‐N appeared to be straightforward. The only explanation suggested is that the antibody was of heterologous origin.