| 1. |
- Hellberg, Åsa, et al.
(författare)
-
An update on the GLOB blood group system and collection.
- 2013
-
Ingår i: Immunohematology. - 0894-203X. ; 29:1, s. 19-24
-
Tidskriftsartikel (refereegranskat)abstract
- The P blood group antigen of the GLOB system is a glycolipid structure, also known as globoside, on the red blood cells (RBCs) of almost all individuals worldwide. The P antigen is intimately related to the Pk and NOR antigens discussed in the review about the P1PK blood group system. Naturally occurring anti-P is present in the serum of individuals with the rare globoside-deficient phenotypes p, P1k, and P2k and has been implicated in hemolytic transfusion reactions as well as unfavorable outcomes of pregnancy. The molecular genetic basis of globoside deficiency is absence of functional P synthase as a result of mutations at the B3GALNT1 locus. Other related glycolipid structures, the LKE and PX2 antigens, remain in the GLOB blood group collection pending further evidence about the genes and gene products responsible for their synthesis.
|
|
| 2. |
- Hellberg, Åsa, et al.
(författare)
-
P1PK: the blood group system that changed its name and expanded.
- 2013
-
Ingår i: Immunohematology. - 0894-203X. ; 29:1, s. 25-33
-
Tidskriftsartikel (refereegranskat)abstract
- The antigens in the P1PK blood group system are carried on glycosphingolipids. The system currently includes three different antigens, P1, Pk, and NOR. The P1 antigen was disovered in 1927 by Landsteiner and Levine, and Pk and NOR were described in 1951 and 1982, respectively. As in the ABO system, naturally occurring antibodies of the immunoglobulin (Ig) M or IgG class, against the missing carbohydrate structures, can be present in the sera of people lacking the corresponding antigen. Anti-P1 is generally a weak and cold-reactive antibody not implicated in hemolytic transfusion reaction (HTR) or hemolytic disease of the fetus and newborn while Pk antibodies can cause HTR, and anti-NOR is regarded as a polyagglutinin. A higher frequency of miscarriage is seen in women with the rare phenotypes p, P1k, and P2k. Furthermore, the Pk and P1 antigens have wide tissue distributions and can act as host receptors for various pathogens and toxins. Why p individuals lack not only Pk and P expression but also P1 has been a longstanding enigma. Recently, it was shown that the same A4GALT-encoded galactosyltransferase synthesizes both the P1 and Pk antigens and that a polymorphism in a new exon in this gene predicts the P1 and P2 phenotypes.
|
|
| 3. |
- Suppiah, Ravi, et al.
(författare)
-
A cross-sectional study of the Birmingham Vasculitis Activity Score version 3 in systemic vasculitis.
- 2011
-
Ingår i: Rheumatology (Oxford, England). - : Oxford University Press (OUP). - 1462-0332 .- 1462-0324. ; 50, s. 899-905
-
Tidskriftsartikel (refereegranskat)abstract
- Objective. Assessment of disease activity in vasculitis can be achieved using the BVAS, a clinical checklist of relevant symptoms, signs and features of active disease. The aim of this study was to revalidate the BVAS version 3 (BVAS v. 3) in a cohort of patients with systemic vasculitis. Methods. A total of 238 patients with vasculitis from seven countries in Europe were evaluated at a single time point. Spearman's correlation coefficients were calculated between BVAS v. 3 scores, vasculitis activity index (VAI), physician's global assessment (PGA), the physician's treatment decision, CRP and the vasculitis damage index (VDI) to demonstrate that the BVAS v. 3 measures disease activity. Results. WG (63%), Churg-Strauss syndrome (9%) and microscopic polyangiitis (9%) were the most common diagnoses. The BVAS v. 3 showed convergent validity with the VAI [ρ = 0.82 (95% CI 0.77, 0.85)], PGA [ρ = 0.85 (95% CI 0.81, 0.88)] and the physician's treatment decision [ρ = 0.54 (95% CI 0.44, 0.62)]. There was little or no correlation between BVAS v. 3 and the CRP level [ρ = 0.18 (95% CI 0.05, 0.30)] or with the VDI [ρ = -0.10 (95% CI 0.22, 0.03)]. The inter-observer reliability was very high with an intra-class correlation coefficient (ICC) of 0.996 (95% CI 0.990, 0.998) for the total BVAS v. 3 score. Conclusion. The BVAS v. 3 has been evaluated in a large cohort of patients with vasculitis and the important properties of the tool revalidated. This study increases the utility of the BVAS v. 3 in different populations of patients with systemic vasculitis.
|
|
| 4. |
- Suppiah, Ravi, et al.
(författare)
-
Measurement of damage in systemic vasculitis: a comparison of the Vasculitis Damage Index with the Combined Damage Assessment Index
- 2011
-
Ingår i: Annals of the Rheumatic Diseases. - : BMJ. - 1468-2060 .- 0003-4967. ; 70:1, s. 80-85
-
Tidskriftsartikel (refereegranskat)abstract
- Objectives To compare the Vasculitis Damage Index (VDI) with the Combined Damage Assessment Index (CDA) as measures of damage from vasculitis. Methods A total of 283 patients with vasculitis from 11 European centres were evaluated in a cross-sectional study using the VDI and CDA. Results Wegener's granulomatosis (58.4%) and microscopic polyangiitis (11.0%) were the most common diagnoses. Agreement between VDI and CDA scores (Spearman's correlation) was 0.90 (95% CI 0.87 to 0.92). There was good correlation between individual comparably evaluated organ systems (Spearman's correlation 0.70-0.94). Interobserver reliability (assessed by intraclass correlation coefficient (ICC)) was 0.94 (95% CI 0.89 to 0.98) for VDI and 0.78 (95% CI 0.63 to 0.93) for CDA. Intraobserver reliability was 0.92 (95% CI 0.83 to 1.00) for VDI and 0.87 (95% CI 0.75 to 1.00) for CDA. A total of 13 items were not used in the VDI compared to 23 in the CDA. Observers agreed that the CDA covered the full spectrum of damage attributable to vasculitis but was more time consuming and thus possibly less feasible for clinical and research purposes. Conclusions The VDI and CDA capture reliable data on damage among patients with vasculitis. The CDA captures more detail but is more complex and less practical than the VDI. Further evolution of damage assessment in vasculitis is likely to include key elements from both instruments.
|
|
| 5. |
- Thuresson, Britt, et al.
(författare)
-
Identification of a novel A4GALT exon reveals the genetic basis of the P1/P2 histo-blood groups.
- 2011
-
Ingår i: Blood. - : American Society of Hematology. - 1528-0020 .- 0006-4971. ; 117:2, s. 678-687
-
Tidskriftsartikel (refereegranskat)abstract
- The A4GALT locus encodes a glycosyltransferase that synthesizes the terminal Galα1-4Gal of the P(k)(Gb3/CD77) glycosphingolipid, important in transfusion medicine, obstetrics and pathogen susceptibility. Critical nucleotide changes in A4GALT not only abolish P(k) formation but also another Galα1-4Gal-defined antigen, P1, which belongs to the only blood group system for which the responsible locus remains undefined. Since known A4GALT polymorphisms do not explain the P1-P(k)+ phenotype, P(2), we set out to elucidate the genetic basis of P(1)/P(2). Despite marked differences (P(1)>P(2)) in A4GALT transcript levels in blood, luciferase experiments showed no difference between P(1)/P(2)-related promoter sequences. Investigation of A4GALT-mRNA in cultured human bone marrow cells revealed novel transcripts containing only the non-coding exon 1 and a sequence (here termed exon 2a) from intron 1. These 5'-capped transcripts include poly-A tails and 3 polymorphic sites, one of which was P(1)/P(2)-specific among >200 donors and opens a short reading frame in P(2) alleles. We exploited these data to devise the first genotyping assays to predict P1 status. P(1)/P(2) genotypes correlated with both transcript levels and P1/P(k) expression on red cells. Thus, P(1) zygosity partially explains the well-known interindividual variation in P1 strength. Future investigations need to focus on regulatory mechanisms underlying P1 synthesis.
|
|
| 6. |
- Westman, Julia, et al.
(författare)
-
Large deletions involving the regulatory upstream regions of A4GALT give rise to principally novel P1PK-null alleles.
- 2014
-
Ingår i: Transfusion. - : Wiley. - 1537-2995 .- 0041-1132. ; 54:7, s. 1831-1835
-
Tidskriftsartikel (refereegranskat)abstract
- Cells of the clinically important p histo-blood group phenotype lack P1, P(k) , and P glycosphingolipid antigens. All cases investigated so far are due to alterations in the 4-α-galactosyltransferase-encoding Exon 3 of A4GALT. Repetitive elements in the genome can mediate DNA rearrangements, the most abundant being the Alu family of repeats.
|
|
| 7. |
- Westman, Julia, et al.
(författare)
-
P1/P2 genotyping of known and novel null alleles in the P1PK and GLOB histo-blood group systems.
- 2013
-
Ingår i: Transfusion. - : Wiley. - 1537-2995 .- 0041-1132. ; 53:11, s. 2928-2939
-
Tidskriftsartikel (refereegranskat)abstract
- The rare but clinically important null phenotypes of the P1PK and GLOB blood group systems are due to alterations in A4GALT and B3GALNT1, respectively. A recently identified single-nucleotide polymorphism in Exon 2a of A4GALT predicts the common P1 and P2 phenotypes but rare variants have not been tested.
|
|
