scholarly journals Changes in the blood group Wright antigens are associated with a mutation at amino acid 658 in human erythrocyte band 3: a site of interaction between band 3 and glycophorin A under certain conditions [see comments]

Blood ◽  
1995 ◽  
Vol 85 (2) ◽  
pp. 541-547 ◽  
Author(s):  
LJ Bruce ◽  
SM Ring ◽  
DJ Anstee ◽  
ME Reid ◽  
S Wilkinson ◽  
...  

The Wright (Wr) blood group antigens, Wra and Wrb, have been suggested to be determined by alleles of the same gene. The Wrb antigen appears to involve both red blood cell (RBC) band 3 and glycophorin A (GPA). We have examined the cDNA sequences of the band 3 and GPA of one of the two known Wr(a+b-) individuals. We show that this individual is homozygous for the mutation Glu658--<Lys in band 3, but has normal GPA. Putative heterozygotes with Wr(a+b+) RBCs have both Glu and Lys at residue 658 of band 3, whereas the common Wr(a-b+) RBC phenotype only have band 3 with Glu658. The Wra and Wrb antigens are determined by the amino acid at residue 658 of band 3 and are antithetical. Examination of the amino acid sequence and Wrb antigen expression of GPA-related hybrid glycophorins suggests that Arg61 of GPA interacts with Glu658 of band 3 to form the Wrb antigen. We suggest that the interaction is stabilized by the presence of anti-Wrb antibodies and that this site of association between GPA and band 3 may be responsible for the previously reported ability of anti-GPA antibodies to decrease the deformability of RBCs.

Blood ◽  
1995 ◽  
Vol 85 (2) ◽  
pp. 541-547 ◽  
Author(s):  
LJ Bruce ◽  
SM Ring ◽  
DJ Anstee ◽  
ME Reid ◽  
S Wilkinson ◽  
...  

Abstract The Wright (Wr) blood group antigens, Wra and Wrb, have been suggested to be determined by alleles of the same gene. The Wrb antigen appears to involve both red blood cell (RBC) band 3 and glycophorin A (GPA). We have examined the cDNA sequences of the band 3 and GPA of one of the two known Wr(a+b-) individuals. We show that this individual is homozygous for the mutation Glu658--<Lys in band 3, but has normal GPA. Putative heterozygotes with Wr(a+b+) RBCs have both Glu and Lys at residue 658 of band 3, whereas the common Wr(a-b+) RBC phenotype only have band 3 with Glu658. The Wra and Wrb antigens are determined by the amino acid at residue 658 of band 3 and are antithetical. Examination of the amino acid sequence and Wrb antigen expression of GPA-related hybrid glycophorins suggests that Arg61 of GPA interacts with Glu658 of band 3 to form the Wrb antigen. We suggest that the interaction is stabilized by the presence of anti-Wrb antibodies and that this site of association between GPA and band 3 may be responsible for the previously reported ability of anti-GPA antibodies to decrease the deformability of RBCs.


Blood ◽  
1996 ◽  
Vol 87 (9) ◽  
pp. 3942-3947 ◽  
Author(s):  
CH Huang ◽  
ME Reid ◽  
SS Xie ◽  
OO Blumenfeld

The Wright (Wra/Wrb) blood group polymorphism is defined by an allelic change (Lys658Glu) in the band 3 protein; nevertheless, the Wrb antigen apparently requires glycophorin A (GPA) for surface presentation. To gain insight into the structural basis for this protein-protein interaction and delineate its relationship with Wrb antigen expression, we investigated GPA and band 3 sequence polymorphisms occurring in rare humans and nonhuman primates. The lack of GPA or amino acid residues 59 through 71 of GPA results in the absence of Wrb from human red blood cells (RBCs) exhibiting the MkMk, En(a-), or MiV phenotype. However, the SAT homozygous cells carried a Glu658 form of band 3 and a hybrid glycophorin with the entire GPA extramembrane domain from residues 1 through 71, yet expressed no Wrb antigen. This finding suggests that formation of the Wrb antigenic structure is dependent on protein folding and that the transmembrane junction of GPA is important in maintaining the required conformation. Comparative analyses of GPA and band 3 homologues led to the identification in the interacting regions of conserved and dispensable amino acid residues that correlated with the Wrb positive or negative status on nonhuman primates. In particular, the chimpanzee RBCs cells expressed Wrb and the Glu658 form of band 3, which is identical to humans, but their GPA contained the Gly rather than Arg residue at position 61. Taken together, the results suggest that (1) Arg61 of GPA and the proposed Arg61-Glu658 charge pair are not crucial for Wrb antigen exhibition and (2) the role of GPA for interaction with band 3, including Glu658, probably involves a number of amino acid residues located in the alpha-helical region and transmembrane junction.


Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 1027-1027 ◽  
Author(s):  
Barbara Ghinassi ◽  
Maria Themeli ◽  
Kai-Hsin Chang ◽  
Gregory Halverson ◽  
Ghazala Hashmi ◽  
...  

Abstract Abstract 1027 Red blood cells (RBC) survive shear forces in the microvasculature because trans-membrane complexes embedded in the lipid bilayer attach their membrane to the cytoskeleton assuring its flexibility. The expression of clinically relevant red blood cell antigens present on these complexes is determined by genetic polymorphisms and their developmental regulation. Therefore, flow cytometry studies of blood group antigens may provide insights both on potential immunogenicity and on membrane structure of ex-vivo generated EBs. Blood group antigen profiles of EBs expanded ex vivo from one AB (three experiments), three CB, the H1 hESC line and one iPS line derived from mononuclear cells from a healthy donor were compared by flow cytometry using commercially available antibodies recognizing antigens present on proteins in the 4.1R [Duffy (Fya and Fy3), Kell (Kell prot, K/k, Kpa/Kpb, Jsb) and glycophorin C (GPC, Ge2)] and ankyrin R [glycophorin A (GPA, CD235a, M and EnaFS) RhAG and band 3 (Wrb)] complexes and on other important membrane proteins [glycophorin B (GPB, s and U), urea transporter (Kidd, Jk3), the complement receptor (CD35) and inhibitors of complement-mediated lysis (CD55 and CD59)]. Controls included DNA genotyping (CB, AB and H1-hESC) (HEA-Bead Chip, Immunocor, Norcross, GA) and immunophenotyping of blood red cells from the same AB and CB. Antigen expression similar to that observed on in vivo generated RBC was considered normal. EBs were generated from AB and CB at day 10 in HEMAser cultures whereas EBs from hESC and iPS were derived using previously optimized protocols. The maturation state was determined by morphological analyses and CD36/CD235a profiles. Irrespective of the stem cell source, the immunophenotype of ex-vivo expanded EBs was consistent with that predicted by genotyping. However, source specific differences in the magnitude of antigen expression and in the changes with maturation were observed (see Figure). Immature EBs from AB expressed normal levels of the antigens present on both the 4.1R (Duffy, Kell, GPC) and ankyrin R (GPA, M/N, EnaFS, RhAG and band 3) complexes. With maturation, expression of 4.1R-associated antigens remained normal while that of ankyrin R associated antigens varied (M decreased and RhAG increased). EBs from CB expressed normal levels of antigens present on the ankyrin R complex and of some of those present on the 4.1R complex (Duffy, Kell protein and GPA). However, expression of epitopes on Kell protein varied with some antigens expressed at normal levels (k and Jsb) and others (Kpa/Kpb) at levels 2x greater than normal. With maturation, CB-derived EBs maintained normal levels of ankyrin R associated antigens while those associated with complex 4.1R became barely detectable. EB from hESC expressed unbalanced levels of proteins associated with both ankyrin R (2x levels of GPA and barely detectable levels of RhAG) and 4.1R [3x levels of Duffy and 2x levels of Jsb (Kell) with normal levels of k and Kpb (Kell) antigens] complexes. The variegation in expression of different epitopes on the same protein observed with CB- and hESC-derived EBs likely reflect altered structural conformation of the complexes rather than differences in protein concentration on the membrane. EBs from iPS, as those from AB, expressed normal levels of antigens present on Ankyrin R and 4.1R complexes which increased with maturation. Irrespective of stem cell sources, EBs expressed normal levels of GPB and Kidd. EBs from AB expressed normal levels of the complement regulatory proteins tested which in the case of CD59 CD59 decreased with maturation. EBs from CB expressed normal levels of CD35 and CD59 but 2x levels of CD55 with expression of CD35 and CD55 decreasing with maturation. EBs from iPS expressed 2x levels of CD35 and CD55 and expression of these antigens was not affected by maturation. The observation that blood group antigenic profiles of ex-vivo generated EBs are consistent with those predicted by DNA-genotyping suggests that these cells are unlikely to be immunogenic for known epitopes. However, the antigen profiles of ankyrin R and 4.1R complexes were normal only for AB and iPS-derived EBs raising the possibility that antigenic deviations seen in EBs derived from CB and hESC may have immunologic or functional consequences in vivo. Disclosures: No relevant conflicts of interest to declare.


Vox Sanguinis ◽  
2000 ◽  
Vol 78 (1) ◽  
pp. 52-56 ◽  
Author(s):  
Jill R. Storry ◽  
Gail Coghlan ◽  
Joyce Poole ◽  
Dolores Figueroa ◽  
Marion E. Reid

Blood ◽  
1993 ◽  
Vol 82 (10) ◽  
pp. 3198-3203
Author(s):  
G Daniels ◽  
MJ King ◽  
ND Avent ◽  
G Khalid ◽  
M Reid ◽  
...  

Glycophorin C (GPC) and glycophorin D (GPD) are homologous sialoglycoproteins in the human red blood cell membrane. Both are thought to be encoded by the GPC gene (GYPC). We report that the rare blood group antigen, Ana, is expressed on GPD but not on GPC. cDNA was synthesized from total RNA obtained from two unrelated, heterozygous Ana+ blood donors and analyzed by the polymerase chain reaction using primers that spanned sequences encoded by the GYPC gene. The expected 412-bp fragment was generated, and sequencing of the amplified product showed a G-->T substitution at nucleotide 67 of the coding sequence, resulting in the substitution of alanine by serine at amino acid residue 23 of GPC and, presumably, residue 2 of GPD. To explain the expression of Ana on GPD but not on GPC, we postulate that the conformation of the amino acid residues at the N-terminal region of GPD determines the antigenic expression as this conformation would be different from that of the same sequence of amino acids occurring within GPC. Other possible reasons for antigen expression on a shorter protein product but not on the full-length protein product of the same gene are discussed. We extrapolate this reasoning to account for the expression of the common GE2 blood group antigen on GPD but not on GPC.


Blood ◽  
1993 ◽  
Vol 82 (6) ◽  
pp. 1913-1920 ◽  
Author(s):  
M Ugorski ◽  
DP Blackall ◽  
P Pahlsson ◽  
SH Shakin-Eshleman ◽  
J Moore ◽  
...  

Abstract Glycophorin A is a heavily glycosylated glycoprotein (1 N-linked and 15 O-linked oligosaccharides) and is highly expressed on the surface of human red blood cells. It is important in transfusion medicine because it carries several clinically relevant human blood group antigens. To study further the role of glycosylation in surface expression of this protein, four mutations were separately introduced into glycophorin A cDNA by site-directed mutagenesis. Each of these mutations blocks N- linked glycosylation at Asn26 of this glycoprotein by affecting the Asn- X-Ser/Thr acceptor sequence. Two of these mutations are identical to the amino acid polymorphisms found at position 28 in the Mi.I and Mi.II Miltenberger blood group antigens. The mutated recombinant glycoproteins were expressed in transfected wild-type and glycosylation- deficient Chinese hamster ovary (CHO) cells. When expressed in wild- type CHO cells and analyzed on Western blots, each of the four mutants had a faster electrophoretic mobility than wild-type glycophorin A, corresponding to a difference of approximately 4 Kd. This change is consistent with the absence of the N-linked oligosaccharide at Asn26. Each of the four mutants was highly expressed on the surface of CHO cells, confirming that, in the presence of normal O-linked glycosylation, the N-linked oligosaccharide is not necessary for cell surface expression of this glycoprotein. To examine the role of O- linked glycosylation in this process, the Mi.I mutant cDNA was transfected into the IdlD glycosylation-deficient CHO cell line. When the transfected IdlD cells were cultured in the presence of N- acetylgalactosamine alone, only intermediate levels of cell surface expression were seen for Mi.I mutant glycophorin A containing truncated O-linked oligosaccharides. In contrast, when cultured in the presence of galactose alone, or in the absence of both galactose and N- acetylgalactosamine, Mi.I mutant glycophorin A lacking both N-linked and O-linked oligosaccharides was not expressed at the cell surface. This extends previous results (Remaley et al, J Biol Chem 266:24176, 1991) showing that, in the absence of O-linked glycosylation, some types of N-linked glycosylation can support cell surface expression of glycophorin A. The glycophorin A mutants were also used for serologic testing with defined human antisera. These studies showed that the recombinant Mi.I and Mi.II glycoproteins appropriately bound anti-Vw and anti-Hut, respectively. They also demonstrated that these antibodies recognized the amino acid polymorphisms encoded by Mi.I and Mi.II rather than cryptic peptide antigens uncovered by the lack of N- linked glycosylation.


Blood ◽  
1993 ◽  
Vol 82 (6) ◽  
pp. 1913-1920 ◽  
Author(s):  
M Ugorski ◽  
DP Blackall ◽  
P Pahlsson ◽  
SH Shakin-Eshleman ◽  
J Moore ◽  
...  

Glycophorin A is a heavily glycosylated glycoprotein (1 N-linked and 15 O-linked oligosaccharides) and is highly expressed on the surface of human red blood cells. It is important in transfusion medicine because it carries several clinically relevant human blood group antigens. To study further the role of glycosylation in surface expression of this protein, four mutations were separately introduced into glycophorin A cDNA by site-directed mutagenesis. Each of these mutations blocks N- linked glycosylation at Asn26 of this glycoprotein by affecting the Asn- X-Ser/Thr acceptor sequence. Two of these mutations are identical to the amino acid polymorphisms found at position 28 in the Mi.I and Mi.II Miltenberger blood group antigens. The mutated recombinant glycoproteins were expressed in transfected wild-type and glycosylation- deficient Chinese hamster ovary (CHO) cells. When expressed in wild- type CHO cells and analyzed on Western blots, each of the four mutants had a faster electrophoretic mobility than wild-type glycophorin A, corresponding to a difference of approximately 4 Kd. This change is consistent with the absence of the N-linked oligosaccharide at Asn26. Each of the four mutants was highly expressed on the surface of CHO cells, confirming that, in the presence of normal O-linked glycosylation, the N-linked oligosaccharide is not necessary for cell surface expression of this glycoprotein. To examine the role of O- linked glycosylation in this process, the Mi.I mutant cDNA was transfected into the IdlD glycosylation-deficient CHO cell line. When the transfected IdlD cells were cultured in the presence of N- acetylgalactosamine alone, only intermediate levels of cell surface expression were seen for Mi.I mutant glycophorin A containing truncated O-linked oligosaccharides. In contrast, when cultured in the presence of galactose alone, or in the absence of both galactose and N- acetylgalactosamine, Mi.I mutant glycophorin A lacking both N-linked and O-linked oligosaccharides was not expressed at the cell surface. This extends previous results (Remaley et al, J Biol Chem 266:24176, 1991) showing that, in the absence of O-linked glycosylation, some types of N-linked glycosylation can support cell surface expression of glycophorin A. The glycophorin A mutants were also used for serologic testing with defined human antisera. These studies showed that the recombinant Mi.I and Mi.II glycoproteins appropriately bound anti-Vw and anti-Hut, respectively. They also demonstrated that these antibodies recognized the amino acid polymorphisms encoded by Mi.I and Mi.II rather than cryptic peptide antigens uncovered by the lack of N- linked glycosylation.


Blood ◽  
1993 ◽  
Vol 82 (10) ◽  
pp. 3198-3203 ◽  
Author(s):  
G Daniels ◽  
MJ King ◽  
ND Avent ◽  
G Khalid ◽  
M Reid ◽  
...  

Abstract Glycophorin C (GPC) and glycophorin D (GPD) are homologous sialoglycoproteins in the human red blood cell membrane. Both are thought to be encoded by the GPC gene (GYPC). We report that the rare blood group antigen, Ana, is expressed on GPD but not on GPC. cDNA was synthesized from total RNA obtained from two unrelated, heterozygous Ana+ blood donors and analyzed by the polymerase chain reaction using primers that spanned sequences encoded by the GYPC gene. The expected 412-bp fragment was generated, and sequencing of the amplified product showed a G-->T substitution at nucleotide 67 of the coding sequence, resulting in the substitution of alanine by serine at amino acid residue 23 of GPC and, presumably, residue 2 of GPD. To explain the expression of Ana on GPD but not on GPC, we postulate that the conformation of the amino acid residues at the N-terminal region of GPD determines the antigenic expression as this conformation would be different from that of the same sequence of amino acids occurring within GPC. Other possible reasons for antigen expression on a shorter protein product but not on the full-length protein product of the same gene are discussed. We extrapolate this reasoning to account for the expression of the common GE2 blood group antigen on GPD but not on GPC.


1992 ◽  
Vol 287 (1) ◽  
pp. 223-228 ◽  
Author(s):  
K Ridgwell ◽  
N K Spurr ◽  
B Laguda ◽  
C MacGeoch ◽  
N D Avent ◽  
...  

The Rh blood-group antigens are associated with human erythrocyte membrane proteins of approx. 30 kDa (the Rh30 polypeptides). Heterogeneously glycosylated membrane proteins of 50 and 45 kDa (the Rh50 glycoproteins) are coprecipitated with the Rh30 polypeptides on immunoprecipitation with anti-Rh-specific mono- and poly-clonal antibodies. We have isolated cDNA clones representing a member of the Rh50 glycoprotein family (the Rh50A glycoprotein). We used PCR with degenerate primers based on the N-terminal amino acid sequence of the Rh50 glycoproteins and human genomic DNA as a template and cloned and sequenced three types of PCR product of the expected size. Two of these products, Rh50A and Rh50B, gave the same translated amino acid sequence which corresponded to the expected Rh50 glycoprotein sequence but had only 75% DNA sequence similarity. The third product (Rh50C) contained a single base deletion, and the translated amino acid sequence contained an in-frame stop codon. We have isolated cDNA clones containing the full coding sequence of the Rh50A glycoprotein. This sequence predicts that it is a 409-amino acid N-glycosylated membrane protein with up to 12 transmembrane domains. The Rh50A glycoprotein shows clear similarity to the Rh30A protein in both amino acid sequence and predicted topology. Our results are consistent with the Rh30 and Rh50 groups of proteins being different subunits of an oligomeric complex which is likely to have a transport or channel function in the erythrocyte membrane. We mapped the Rh50A gene to human chromosome 6p21-qter, showing that genetic differences in the Rh30 rather than the Rh50 genes specify the major polymorphic forms of the Rh antigens.


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