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C Cotorruelo

Publications and source records attributed to C Cotorruelo.

11 recordsLinked to original sources
PubMed2003

Study of phagocytosis of senescent erythrocytes in young and elderly individuals.

There is a decrease in the percentage contribution of a heavy density fraction of red blood cells to whole blood with increasing age. The aim of this study was to investigate in the young and elderly the interaction between monocytes and different erythrocyte suspensions: senescent red blood cells, erythrocytes stored with or without serum, and desialylated red blood cells. The results obtained with senescent red blood cells and erythrocytes stored with serum show the involvement of autologous IgG in the selective removal of erythrocytes. These values were higher in elderly individuals, indicating that this process increases with age. Our observation suggest that desialylation is not involved in the increased removal of erythrocytes observed in elderly individuals.

Adult↗
PubMed2002

Early detection of RhD status in pregnancies at risk of hemolytic disease of the newborn.

The aim of this work was to investigate the presence of the RHD gene in fetal cells obtained from amniotic fluid. We studied 65 samples of amniotic fluid, 11 from RhD-negative mothers sensitized with anti-D alloantibodies. The fetal origin of the DNA was confirmed with the analysis of 1 VNTR locus and 3 STR loci in DNA samples from amniotic fluid and maternal blood. The RHD genotyping was performed in non-contaminated samples (n=62) using a multiplex polymerase chain reaction strategy that yields three amplification products from RhD-positive phenotypes (intron 4 of both RHCE and RHD genes and exon 10 of the RHD gene) and I DNA fragment from RhD-negative phenotypes (intron 4 of the RHCE gene). We genotyped 54 RhD-positive fetuses (8 from RhD-negative sensitized mothers) and 8 RhD-negative fetuses (3 from RhD-negative sensitized mothers). The fetal DNA genotyping allows the diagnosis, from a single amniocentesis, of fetuses at real risk of hemolytic disease of the newborn. When the fetus is determined to be RhD-negative invasive procedures can be avoided.

Amniotic Fluid↗
PubMed2002

Senescent erythrocytes: factors affecting the aging of red blood cells.

Human red blood cells (RBC) have a well-defined lifespan of 120 days affected by many cellular parameters. The aim of the present study was to investigate through a functional assay the effect of some factors in the interaction of erythrocytes with monocytes: heat rigidification, equilibration at different pH and desialyzation. We also studied the interaction between stored RBC and peripheral blood monocytes with this functional erythrophagocytosis assay. Blood samples from 30 volunteer donors were investigated. 1) Senescent (Se) and Young (Y) RBC were obtained by differential centrifugation. 2) Erythrocyte suspensions: Aliquots of each sample were subjected to the following treatments: a) Rigidification by heat (RRBC), b) Equilibration at different pH (5.34, 6.30, 7.33, 9.20) and c) Desialyzation with neuraminidase and trypsin. The functional assay was performed incubating monocytes obtained by glass adherence with these suspensions of RBC. Whole blood samples (n = 20) were stored during different periods of time (0, 7, 14, 21, 28, 35 and 42 days). The erythrophagocytosis assay was performed during six weeks incubating isologous monocytes with RBC from every unit. Negative and positive controls were performed using non sensitized (NSRBC) and sensitized with IgG anti-RhD (SRBC) red cells. The percentage of active monocytes (AM) obtained were: 1) YRBC: 2.8 +/- 0.9 and SeRBC: 17.5 +/- 2.1; 2a) RRBC: 3.0 +/- 0.9; 2b) 10.9 +/- 0.9, 15.5 +/- 0.8, 3.1 +/- 1.0, 4.0 +/- 1.1; 2c) 11.1 +/- 1.4 and 3.9 +/- 1.0; SRBC 32.1 +/- 1.7 and NSRBC: 2.8 +/- 1.5. The % of AM with SeRBC was higher (p < 0.001) than those obtained with NSRBC. The data of AM with RRBC were significantly lower (p < 0.001) than those obtained with SeRBC and SBRC, indicatingthat heat rigidification of RBC does not increase phagocytosis by monocytes. The values of AM obtained from the suspensions of erythrocytes equilibrated at different pH indicate that the acidification of RBC increases the interaction with monocytes. The % AM with neuraminidase treated RBC was higher than those observed with YRBC and NSRBC (p < 0.001). No modifications were observed with trypsin treated RBC. These results suggest that the loss of sialic acid may be involved in the physiological phagocytosis. The values of AM of stored whole blood were: 2.3 +/- 1.3, 2.7 +/- 1.3, 4.4 +/- 1.6, 6.7 +/- 1.2, 9.6 +/- 1.0, 11.7 +/- 0.8 and 13.0 +/- 1.2. The results showed a significant increase in the % of AM as a function of the preservation time from 2,3 +/- 1,3 for the first day to 13,0 +/- 1,2 for the 42nd day (p < 0.001). The data obtained in this ex vivo model show a significant increase (p<0.001) in the phagocytosis of RBC equilibrated at low pH, desialinized (greater than 80%) with neuraminidase and stored for over 28 days. These factors would be involved in erythrocyte removal via phagocytosis during tissular homeostasis.

Cellular Senescence↗
PubMed2001

Erythrophagocytosis assay in patients with autoimmune hemolytic anemia.

The aim of this paper is to evaluate the erythrophagocytosis assay (EA) in patients with autoimmune hemolytic anemia (AIHA). Direct antiglobulin test (DAT), indirect antiglobulin test (IAT) and EA were performed in blood samples from 46 patients with presumed AIHA. The EA was carried out incubating patients' erythrocytes and peripheral blood monocytes. A total of 200 monocytes were analysed to determine the percentage of active phagocytic cells (% APC). In 9 of these patients the applied treatment was evaluated by DAT, IAT and EA. In 14 transfusion requirements, the compatibility tests and EA were performed. For EA, patients' monocytes were incubated with erythrocytes from previously selected units sensitized with patients' sera. The % of APC was 32.1 +/- 1.7 in 35 patients with positive DAT and 17.8 +/- 1.3 in 11 patients with negative DAT. This last value was significantly higher than that with negative controls (3.7 +/- 0.3)(p < or = 0.01). As regards the applied treatment, patients with a successful response (n = 6) showed a significant decrease in the initial % APC (31.8 +/- 1.6 to 15.3 +/- 2.4; p < or = 0.05) while DAT and IAT remained positive. In those patients who required blood transfusion the compatibility tests were positive with all the units to be transfused, whereas the % APC varied for each one. Blood units were selected according to the lower % APC.

Anemia, Hemolytic, Autoimmune↗
PubMed2001

[Rh system genotyping in amniotic fluid].

The aim of this work was to determine the presence of the RHD gene in fetal cells obtained from amniotic fluid (AF). We studied 65 samples of AF, 11 from RhD- mothers sensitized with anti-D. The fetal origin of the DNA was confirmed with the analysis of 1 VNTR locus and 3 STR loci in DNA samples from AF and maternal blood. The RHD genotyping was performed in non contaminated samples (n = 62) using a multiplex PCR strategy that yields 3 amplification products from RhD+ phenotypes and 1 DNA fragment from RhD- phenotypes. We genotyped 54 RhD+ fetuses (8 from RhD- sensitized mothers) and 8 RhD- fetuses (3 from RhD- sensitized mothers). Fetal DNA genotyping allows the diagnosis, from a single amniocentesis, of fetuses at real risk of hemolytic disease of the newborn. When the fetus is determined to be RhD- all invasive procedures can be avoided.

Amniotic Fluid↗
PubMed2000

Molecular determination of RhD phenotype by DNA typing: clinical applications.

Rhesus D (RhD) typing is performed by agglutination methods; however, in clinical situations where these techniques cannot be performed, RhD DNA typing is an alternative approach. The Rh antigens are encoded by the RHD and RHCE genes. In RhD-negative individuals the RHD gene is absent or grossly deleted, but variations in the arrangement of the RH locus in different populations are emerging. The aim of this study was to analyse the gross organization of the RH genes in our population using a previously described multiplex polymerase chain reaction (PCR) method with some modifications. We studied 253 DNA samples from Argentinian blood donors, 15 samples with a reduced expression of the D antigen and 1 Dc- phenotype. We evaluated the clinical utility of this method to ascertain the RhD antigen in 10 patients with warm-type autoimmune haemolytic anaemia (AIHA) and 14 samples of amniotic fluids. All Rh phenotypes were properly characterized and no discrepancies with serological typing were found. Analyses performed in the Dc- phenotype suggest the presence of a hybrid RHCE-RHD gene. DNA typing confirmed the RhD-negative type of one AIHA sample in which serological tests were inconclusive. Foetal DNA typing correctly indicated the RhD in every foetus. VNTR (variable number of tandem repeats) and STR (short tandem repeats) analysis detected maternal contamination in two amniocentesis samples and confirmed the foetal origin of 12. This multiplex PCR strategy is suitable for RhD determination in clinical situations in which serological typing cannot be accomplished with its usual ease.

Alleles↗
PubMed1999

Senescent erythrocytes: modification of rheologic properties, antigenic expression and interaction with monocytes.

Human erythrocytes have a well-defined lifespan of 120 days. Their eventual removal from circulation is a complex process affected by many cellular parameters, making them susceptible to sequestration in the spleen and other organs. The purpose of this study was to investigate putative changes in rheologic properties, antigenic expression and interaction with monocytes of senescent erythrocytes (SE). SE and young erythrocyte (YE) fractions were obtained by differential centrifugation from 20 healthy donor blood samples. Membrane rheomechanic properties (by diffractometric method), ABO and MN antigens reactivity and erythrophagocytosis by peripheral monocytes were investigated in each fractions. SE showed a little decrease in the deformability index and an increase of both membrane elastic modulus and surface viscosity. The studies performed indicate a decreased expression in the antigens of both blood group systems studied (p < 0.01) and an increased rate of erythrophagocytosis by monocytes in SE compared to YE (p < 0.01). The significant modifications in the biomechanic properties of senescent red blood cell membrane and the loss of antigenic expression could lead to physiological phagocytosis.

Antigens↗