PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “P Blood-Group System”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed1977

Acid elution of blood group antibodies from intact erythrocytes.

Human IgM and IgG antibodies against blood group antigens (A, B, D, C, c, E, e, Fya, K), autoantibodies and mouse IgM and IgG antibodies against sheep erythrocytes have been eluted from intact human and sheep red cells by glycine-HCl buffer, pH 3.0. The yield of human antibodies was higher with acid than with heat and ether elution, and the contamination of hemoglobin in the eluate was negligible. The acid elution method is very simple and rapid and, therefore, highly suitable for experimental as well as routine immunohematological work.

ABO Blood-Group System↗
PubMed1976

[A serogenetic approach to the study of Alzheimer's disease (author's transl)].

The analysis of 15 hereditary controlled blood characteristics in 57 Alzheimer-patients revealed abnormalities in the distribution of ABO-blood-groups and phenotypes in the third component of complement system. These data indicate that the phenogenesis of the Alzheimer syndrome is multiconditional and is obviously influenced by selective processes of immuno-genetic factors. This selective vulnerability offers a lead into the elucidation of amyloid deposition in Alzheimer's disease.

ABO Blood-Group System↗
PubMed1976

Detection of A1A2 and A2AAm1 heterozygotes among human A blood group phenotypes.

From the variations of alpha-N-acetylgalactosaminyltransferases activities with the pH, evidence was obtained for the recognition of A1A2 heterozygotes in normal A blood group sera. Besides, unusual transferase properties associated with two A2 sera from individuals out of AAm1 siblings, lead to the identification of the very infrequent A2AAm1 genotypes. These results strongly support the simultaneous coexistence of both A1 and A2 transferases in heterozygotes' sera, and bring some new information on the genetical background of the Am phenotype. The meaning of transferase properties directly determined on whole sera is briefly discussed.

ABO Blood-Group System↗
PubMed1977

Effect of heparin on complement activation and lysis of paroxysmal nocturnal hemoglobinuria (PNH) red cells.

The effect of heparin upon the binding of the third component of complement (C3) to PNH red cells in vitro and their subsequent hemolysis is described. Heparin, in increasing concentrations, progressively inhibits membrane C3 fixation and hemolysis when the classic complement pathway is activated by anti-red cell antibodies. Heparin has a biphasic effect upon membrane C3 fixation and hemolysis when complement is activated in serum at decreased ionic strength (sucrose lysis) or in serum at decreased pH (Ham test). Heparin in concentrations above 2 U/ml inhibits C3 binding and hemolysis while lower concentrations of heparin enhance the consequences of complement activation by these two procedures. This enhanced complement activation may explain the increased hemolysis sometimes reported in PNH patients treated with heparin, and suggests that heparin may aggravate the consequences of pathologic alternative pathway complement activation in other diseases.

Binding Sites, Antibody↗
PubMed1975

Bone marrow transplantation in man.

Bone marrow transplantation is emerging as a viable therapeutic approach to a number of diseases that are usually or uniformly fatal. We review here recent experiences in bone marrow transplantation in man at UCLA and in various other institutions throughout the world. We examine marrow transplantation in immunodeficiency diseases, acute leukemia, and aplastic anemia and consider the problems of infection in the transplant recipients. The applications of tissue typing to marrow transplantation and immunologic manipulations, which may influence engraftment and graft-versus-host disease, are also reported.

ABO Blood-Group System↗
PubMed1975

Genetic studies in the Markham Valley, northeastern Papua New Guinea: gamma globulin (Gm and Inv), group specific component (Gc) and ceruloplasmin (Cp) typing.

Genetic studies in the Markham Valley, northeastern Papua New Guinea; Gamma globulin (Gm and Inv), group specific component (Gc) and ceruloplasmin (Cp) typing. M. S. Schanfield, Eugene Giles and H. Gershowitz, Department of Human Genetics, University of Michigan, Ann Arbor, Michigan 48104. Immunoglobulin allotyping was carried out on 680 serum samples from inhabitants of the Markham Valley, Papua New Guinea (seven villages speaking the same Melanesian [PAP] speaking village). Family and population data verified the presence of Gm-ag, G-ab and Gm-afb among the MN speakers and Gm-ag, Gm-axg, Gm-ab and Gm-afb among the PAP speakers. The frequency of Gm-ag was between 0.048 and 0.235, while the frequency of Gm-ab was between 0.427 and 0.627 and the frequency of Gm-afb ranged between 0.261 and 0.424 among the seven MN villages; the single PAP village had frequencies of 0.568, 0.160, 0.213 and 0.059 for Gm-ag, Gm-axg, Gm-ab and Gm-afb respectively. The frequency of Inv1 ranged between 0.034 and 0.095 in the MN villages and 0.014 in the PAP village. The rare occurrence of Gm(x) without Gm(g) was explained by the presence of a Gm-axfb haplotype, while in two PAP families the presence of Gm(x) without Gm(g) was explained by the abnormally weak expression of Gm(g) in a Gm-axg haplotype. A total of 654 sera were typed for Gc, with the seven MN villages ranging between 0.350 and 0.650 for Gc-1, 0.312 and 0.575 for Gc-2 and between 0.017 and 0.112 for Gc-Ab; the single PAP village had a value of 0.627 for Gc-1, 0.165 for Gc-2 and 0.208 for Gc-Ab. A total of 693 sera were tested for ceruloplasmin type. All showed the common Cp(b) phenotype.

ABO Blood-Group System↗
PubMed2025

Long-read DNA sequencing resolves a rare case of alloimmune hemolysis mimicking autoimmune hemolysis.

BACKGROUND: Immune hemolytic anemia poses a significant challenge in transfusion medicine, as identification of underlying alloantibodies can be masked by warm and/or cold autoantibodies. This increases the risk of transfusing incompatible blood, which can precipitate or exacerbate hemolysis. Identifying alloantibodies in the presence of autoantibodies remains difficult with standard serologic and genotypic methods, often delaying accurate diagnosis and appropriate transfusion strategies. CASE REPORT: We describe a 63-year-old woman with autoimmune hemolytic anemia who suffered near-fatal hemolysis following transfusion. Despite extensive serologic and genotypic testing, the cause of her hemolytic transfusion reactions remained elusive. Given her clinical course and transfusion history, we hypothesized that her acute hemolytic transfusion reactions could be due to immune sensitization to a high-incidence RBC antigen. Research whole-genome long-read sequencing (LRS) revealed homozygosity for a rare KEL*02N.16 allele, consistent with a rare Ko phenotype, which was validated by Sanger sequencing. Retrospective serologic testing with Ko RBCs further confirmed alloimmunization within the Kell system. CONCLUSION: This case highlights the limitations of conventional serologic and genotypic methods in detecting rare blood group phenotypes, and emphasizes the diagnostic power of long-read sequencing in transfusion medicine. Early molecular testing in complex hemolytic cases can facilitate targeted transfusion strategies, reduce the risk of severe hemolysis, and improve patient outcomes. As sequencing technologies become more accessible, they have the potential to revolutionize blood group typing and alloimmunization risk assessment in clinical practice.

Humans↗
PubMed2026

Plasmodium knowlesi can adapt to infect Duffy-negative erythrocytes.

Plasmodium knowlesi, a zoonotic malaria species, has become a significant public health concern in Southeast Asia. In regions such as Malaysia and southern Thailand, P knowlesi incidence has risen, even as other human malaria parasites are nearing elimination. Similar to its close relative Plasmodium vivax, P knowlesi relies on the Duffy antigen receptor for chemokine (DARC) as a key receptor for erythrocyte invasion. Only Duffy-positive individuals are thought to be susceptible to clinical infection. Here, we demonstrate that P knowlesi possesses greater invasion plasticity than previously recognized. This parasite can bypass the need for DARC, as shown by its in vitro adaptation to invade and replicate within Duffy-negative (Fy-) erythrocytes. This adaptation is stable and independent of DARC binding, enabling the adapted parasite line to be maintained in Fy- erythrocytes and to resist inhibition by α-DARC antibodies. Genomic analysis identified a genomic recombination event between the parasite's dbpα and dbpγ genes, resulting in a new chimeric gene dbpαγ. Using CRISPR-Cas9 targeted reversion, we could demonstrate that dbpαγ is essential for invasion of Fy- erythrocytes. These findings shed new light on the invasion plasticity of P knowlesi, with implications for the parasite's potential spread beyond Southeast Asia and for understanding the complex host-cell specificity and atypical invasion pathways seen in P vivax.

Plasmodium knowlesi↗
PubMed1975

HL-A matching and kidney-graft survival. Scandiatransplant report.

The follow-up of 523 kidney transplants with grafts from full-house donors shows a significant (p less than 0.02) correlation between the graft survival and the HL-A match grade. There was no indication in this study that kidneys from blood-group O donors do better in group O recipients than in non-O recipients. Neither was it possible to show any effect of matching for either of the haplotypes, HL-A1,8, HL-A3,7, or HL-A2,12.

ABO Blood-Group System↗
PubMed1977

Treatment of aplastic anemia by marrow transplantation from HLA identical siblings. Prognostic factors associated with graft versus host disease and survival.

73 consecutive patients with severe aplastic anemia were treated by marrow transplantation from hematologically normal HLA identical siblings. 68 patients lived long enough to document marrow engraftment. 21 rejected the graft and 19 of these died. 47 sustained engraftment and 18 of these died. In 16 patients, death was associated with graft versus host disease. 29 patients with sustained engraftment are alive with complete hematologic restoration between 8 mo and 5 yr. This analysis, by using a proportional hazards regression model, was directed at identifying factors that predicted survival (and absence of graft versus host disease). Of the 24 factors entered into the analysis only two strongly correlated with survival: (a) sex match of donor and recipient (P less than 0.01), and (b) absence of refractoriness to random donor platelets at the time of transplantation (P less than 0.05). Refractoriness adversely influenced the survival of the sex mismatched patients, These data suggest that X and Y-associated transplantation antigen systems are important determinants of the outcome of marrow grafts between HLA identical siblings for the treatment of aplastic anemia. The machanism by which refractoriness to random donor platelets influences survival is currently unclear.

ABO Blood-Group System↗