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A Pirkola

Publications and source records attributed to A Pirkola.

17 recordsLinked to original sources
PubMed1995

An enzyme-linked immunosorbent assay for the quantitative determination of anti-D in plasma samples and immunoglobulin preparations.

Here we present an enzyme-linked immunosorbent assay (ELISA) on microtiter plates for the quantitative determination of anti-D. This method is based on the solubilization of red blood cells sensitized with anti-D and the subsequent measurement of immunoglobulin G by ELISA. The measuring range of the assay is 40-5,000 IU/ml and the lowest quantifiable concentration in plasma is 0.5 IU/ml. The interassay relative standard deviation for concentrations above 130 IU/ml ranges from 3.2 to 8.1% and below 50 IU/ml from 10.5 to 19.7%. Comparison of ELISA with automated hemagglutination shows that the results of the two assays correlate well: r = 0.992, n = 26. The assay was validated for donor plasma samples and anti-D immunoglobulin preparations and it can also be used in assessing the severity of Rh (D) hemolytic disease during pregnancy.

Antibody Specificity↗
PubMed1994

MAR, a novel high-incidence Rh antigen revealing the existence of an allelic sub-system including Cw (Rh8) and Cx (Rh9) with exceptional distribution in the Finnish population.

We present new genetic evidence obtained from population studies on Finns and from the studies on Finnish blood donors as well as their selected families using an antibody that defines a novel high-incidence Rh antigen MAR. Anti-MAR antibody shows an antithetical relationship to both anti-Cw and anti-Cx. The Rh antigens Cw (RH8) and, more strikingly, Cx (RH9) have each an exceptionally high frequency in Finns. Our studies on their genetic relationship indicate that the three antigens Cw, Cx and MAR behave as if being determined by alleles of the same Rh sub-system. Furthermore, we conclude that this sub-system manifests an inheritance pattern that is distinct from but analogous to that of the two well-known allelic sub-systems of C/c and E/e antigens.

Adult↗
PubMed1988

A N-acetyllactosamine-specific cell-binding activity in a plant pathogen, Erwinia rhapontici.

A strain of the phytopathogenic bacterial species, Erwinia rhapontici, was found to cause hemagglutination of human erythrocytes that was specifically inhibited by beta-galactosides. Of the monosaccharides tested, N-acetyl galactosamine and galactose efficiently inhibited the hemagglutination. The most potent inhibitor identified was Ga1 beta 1-4GlcNAc that was 30-100-fold more potent than Ga1 beta 1-3GlcNac or Ga1 beta 1-3GalNAc. Fetuin had no effect on the hemagglutination whereas asialofetuin was inhibitory. No blood group specificity was found for the hemagglutinin. These findings indicate that the E. rhapontici strain possesses a novel bacterial cell-binding activity with specificity for terminal N-acetyllactosamine residues.

Acetylgalactosamine↗
PubMed1987

WES, a 'new' infrequent blood group antigen in Finns.

A previously unrecognized infrequent blood group antigen WES occurs with a frequency of 0.56% in the Finnish population, but has an ethnically restricted distribution. Apart from Finns it was found only in 2 donors, most likely of African origin, among 4,655 people tested who represented many different ethnic groups. WES is shown to be a dominant autosomally inherited character different from previously published infrequent antigens. The data allow exclusion from almost all established blood group systems. The WES antigen is destroyed by enzymes alpha-chymotrypsin and pronase. It is also present in plasma of WES+ individuals. Evidence suggests that the soluble form of the antigen is a high molecular weight protein constituent of plasma. Unlike many other antigens present on red cells as well as in plasma, the WES antigen is well developed on red cells of neonates and can also be found in cord serum.

Adult↗
PubMed1983

Familial aniridia and translocation t(4;11)(q22;p13) without Wilms' tumor.

A family with dominantly inherited aniridia in three generations is presented. All three patients had an apparently balanced chromosome translocation t(4;11)(q22;p13). The patients were otherwise clinically normal and without signs of Wilms' tumor; their erythrocyte catalase activities were within the normal range. We suggest that in this family aniridia is caused either by a submicroscopic deletion at the translocation breakpoint 11p13 or by a position effect on the same chromosome segment. Furthermore, the loci for aniridia and Wilms' tumor susceptibility are separate. It follows that the WAGR complex is caused by a mutation of more than one gene located at 11p13. The theoretical implications of a presumably defective allele causing a mendelian dominant phenotype are discussed.

Chromosome Banding↗
PubMed1981

Nea, new blood group antigen in Finland.

A previously unrecognized blood group antigen is described. The antigen was shown to be different from many rare blood group antigens, to be inherited as an autosomal dominant character and not to be closely linked to the established blood group systems nor to several other polymorphic markers of blood. The antigen is well developed at birth. About 5% of Finns have this antigen. In contrast only 1 donor in 502 Swiss blood donors and 2 unrelated donors in 395 Swedish blood donors were found to be positive for the antigen. The antigen is provisionally called Nea and the respective antibody anti-Nea. At least three Na(a+) blood units were given to a patient on different occasions before anti-Nea was detected in compatibility tests. Since the discovery of the first anti-Nea, three additional examples of this antibody have been identified in serum from multitransfused patients. Anti-Nea is capable of shortening the in vivo survival of transfused incompatible Ne(a+) cells.

Aged↗
PubMed1980

External quality control in blood transfusion serology: results from the Finnish proficiency testing programme in immunohaematology, 1976-1978.

Results from the Finnish interlaboratory proficiency testing programme in immunohaematology from 1976 to 1978 are reviewed. The results show excellent accuracy of ABO grouping (100% correct). In Rh (D) grouping the detection of weak D antigen (Du) offered difficulties due to insufficient methodology. Also a sample from a donor with a positive direct antiglobulin reaction created confusion in Rh (D) grouping. The screening of atypical antibodies in serum was performed excellently (100% correct); the antibody coating of red cells, however, was detected by only 83.3% of the participants. The accuracy of compatible crossmatches was good (on average 98.7% correct); the accuracy of incompatible crossmatches, however, was poorer (on average 88.1% correct). A considerable methodological variation in compatibility testing is suggested to be responsible for the poor performance. The performance of individual laboratories seemed to correlate with their position in the health service organization, and with the level of internal quality control procedures.

ABO Blood-Group System↗
PubMed1976

Absence of the major sialoglycoprotein in the membrane of human En(a--) erythrocytes and increased glycosylation of band 3.

The human En(a-) blood group is a rare recessive trait. These erythrocytes lack the major membrane sialoglycoprotein (PAS1, MN protein, or glycophorin) and contain a decreased amount of PAS2 as demonstrated by radiolabeling of surface porteins and chemical techniques. A third glycoprotein, Band 3, contains two labeled oligosaccharide chains; the more complex oligosaccharide has a higher molecular weight in En(1-) cells than in normal cells. A fourth glycoprotein, PAS3, is present in usual amounts in En(a-) cells. Cells heterozygous for En(a) are intermediate in these respects. The sialic acid is decreased in En(a-) cells, but the total carbohydrate is similar in the different membranes. The glycolipids are present in normal amounts but are much more exposed to galactose oxidase in En(a-) cells than in normal cells.

Amino Acids↗
PubMedDate not supplied

Demonstration of anti-Wrb in a second serum containing anti-Ena.

Many persons who are of a "deletion" or "null" phenotype with regard to a particular blood group system, form a complex specificity antibody or mixture of antibodies, when immunized. Recently, we demonstrated that M.E.P., the En(a-), Wr(a- b-) proposita in a family described by Darnborough has at least, anti-Ena and anti-Wrb in her serum. We suggested that the same two antibodies might be present in the serum of G.W., the En(a-), Wr(a- b-) propositus in the family reported by Furuhjelm et al. We have now been able to confirm that G.W.'s serum does contain antiEna and anti-Wrb and that the antibodies can be separated by adsorption. Because, at this time, it is not known if En(a-), Wr(a- b-) people lack other common antigens from their red blood cells, the possibility remains that the anti-Ena, separated from the anti-Wrb, might be a mixture of antibodies. These findings are important in that they show that reported typings for Ena were actually performed with mixtures of at least anti-Ena and anti-Wrb. Anti-Ena, lacking antiWrb, can be made only by adsorption of a serum containing the two antibodies, onto En(a+), Wr(a+b-) red blood cells, with recovery of the anti-Ena by elution.

Antibody Specificity↗