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J Moulds

Publications and source records attributed to J Moulds.

At least 19 recordsLinked to original sources

The Dr hemagglutinin, afimbrial adhesins AFA-I and AFA-III, and F1845 fimbriae of uropathogenic and diarrhea-associated Escherichia coli belong to a family of hemagglutinins with Dr receptor recognition.

The receptor specificities of four Escherichia coli cloned hemagglutinins, AFA-I, AFA-III, F1845 fimbriae, and the Dr hemagglutinin were studied. Evidence is provided that all four hemagglutinins recognize as their receptor the Dr blood group antigen. However, results of experiments using enzyme-treated erythrocytes and monoclonal antibodies indicate that the four adhesins recognize different epitopes on the Dr antigen and thus constitute a family of Dr receptor-recognizing bacterial adhesins. Furthermore, the same results suggest that the Dr antigen itself may be divided into subcomponents on the basis of bacterial adhesins.

Adhesins, Escherichia coli

A hemagglutinin of uropathogenic Escherichia coli recognizes the Dr blood group antigen.

A receptor moiety and blood group substance recognized by the O75X adhesin was studied. Well-defined erythrocytes representing different blood group systems and bacterial derivatives carrying plasmid pBJN406 encoding the adhesin were used in a direct hemagglutination assay. We showed that Dr blood group antigen, a component of the IFC blood group complex, is the receptor for the O75X fimbrialike adhesin (Dr hemagglutinin) of uropathogenic Escherichia coli. The molecule recognized by the Dr hemagglutinin on Dr blood group substance is a chloramphenicol-like structure. The inhibitory effect of the active compounds indicates that a tyrosine-containing molecule could be a natural receptor for the Dr hemagglutinin. Dr blood group substance was found in tubular basement membrane and Bowman's capsule of the human kidney. Specific attachment of a Dr hemagglutinin-positive bacterial strain to the kidney substructures was inhibited by chloramphenicol.

Bacterial Adhesion

Presence of the Dr receptor in normal human tissues and its possible role in the pathogenesis of ascending urinary tract infection.

The Dr hemagglutinin of uropathogenic Escherichia coli recognizes the Dra blood group antigen, a component of the IFC or Cromer-related blood group complex. The present report used the Dr hemagglutinin to demonstrate location of the Dr receptor in selected human tissues and to evaluate the possible use of this lectin as a tissue marker recognizing sites sensitive for bacterial colonization. It was found that the Dr receptor was expressed in different parts of the digestive, urinary, genital, and respiratory tracts, and skin. Intense staining by Dr hemagglutinin was shown in colonic, bronchial, and endometrial glands, and skin eccrine sweat glands. Structures of the urinary tract showing strong fluorescence were renal tubular basement membrane, Bowmans' capsule, and transitional epithelium. The role of Dra antigen as receptor for adhesion for Dr-positive E. coli in ascending colonization of urinary tract and the possible importance of Dra in human pathology is discussed.

Antigens, Bacterial

Hybrid glycophorins from human erythrocyte membranes. Isolation and complete structural analysis of the novel sialoglycoprotein from St(a+) red cells.

Human red cells from donor Pj carry the Sta blood group antigen and an unusual sialoglycoprotein of 24 kDa molecular mass tentatively identified as a hybrid molecule of the anti-Lepore type [Blanchard et al. (1982) Biochem. J. 203, 419-426]. This component is resistant towards proteinase treatment and was purified from trypsin-treated and chymotrypsin-treated Pj erythrocytes. The molecule is composed of 99 amino acid residues whose alignment was established following manual and automatic sequencing of cyanogen bromide, trypsin, chymotrypsin and V8 proteinase peptides. The polypeptide chain comprises residues 1-26/28 of glycophorin B and residues 59/61-131 of glycophorin A. The sugar composition resembles that of glycophorin B, indicating the absence of an N-glycosidic chain. Identical sequences were obtained from analyses of the 24-kDa component purified from unrelated St(a+) donors. These results support the hypothesis that glycoprotein Pj represents a B-A hybrid molecule which is encoded by a new gene product resulting from an unequal crossing-over between the genes coding for the polypeptide chains of the glycophorins A and B. The novel molecule carries both N and Sta blood group antigens. The N activity is clearly understandable from the sequence of the five N-terminal residues (Leu and Glu at positions 1 and 5 respectively). Inhibition studies with the untreated and chemically modified hybrid glycoprotein indicate that the Sta determinant is located within residues approximately 25-30 of the molecule, which corresponds to the newly formed sequence found neither in glycophorin A nor in glycophorin B.

Amino Acid Sequence

Hybrid glycophorins from human erythrocyte membranes. I. Isolation and complete structural analysis of the hybrid sialoglycoprotein from Dantu-positive red cells of the N.E. variety.

The hybrid glycophorin in Dantu-positive human erythrocytes of the N.E. variety was not cleaved by treatment of intact cells with various proteases, in contrast to normal glycophorins. Therefore, it could be purified by phenol/saline extraction of membranes from trypsin-treated and chymotrypsin-treated red cells and subsequent gel filtration in the presence of Ammonyx-LO. The complete structure of the hybrid molecule, comprising 99 amino acid residues, was elucidated by sequence analyses of peptides prepared by chymotrypsin, trypsin, cyanogen bromide or V8 proteinase treatment. The N-terminal 39 residues and the glycosylation of the molecule were found to be indistinguishable from those of blood-group-s-specific glycophorin B. Conversely, the residues 39-99 were shown to be identical with the residues 71-131 of the major blood-group M-active or N-active sialoglycoprotein (glycophorin A). Hemagglutination inhibition assays revealed that the Dantu antigen represents a labile structure. The receptor might be located within the residues approximately 28-40 of the hybrid glycophorin, as judged from the effects of modifications of membranes. Our data provide an explanation for the previous findings that Dantu-positive cells (N.E. type) exhibit a protease-resistant N antigen and a qualitatively altered s antigen.

Amino Acids

The Dantu erythrocyte phenotype of the NE variety. I. Dodecylsulfate polyacrylamide gel electrophoretic studies.

Red cell membranes from patient NE, Mr. Dantu and 16 additional Black individuals, positive for the low-frequency MNSs-system antigen Dantu, were studied by dodecylsulfate polyacrylamide gel electrophoretic techniques. The content of the major, blood group M- or N-active sialoglycoprotein (glycophorin A, GP A) was found to be decreased by about 57%. The blood group S- or s-active sialoglycoprotein (GP B) was decreased by about 51% in membranes from proven Dantu/U heterozygotes and not detectable in those from patient NE and other Dantu+U- individuals. Donor NE was shown to exhibit the genotype Dantu/u. Dantu-positive cells exhibit a proteinase-resistant GP B-GP A hybrid with an apparent molecular mass of 29 KDa whose intramembraneous and cytoplasmic domains were shown to be similar to those of GP A. The molar hybrid: GP A ratio in all cells was found to be about 2.4: 1, indicating that the NE variety of the Dantu phenotype is much more frequent than the Ph or MD types. The significance of an additional minor 'new' component (molecular mass 21 KDa) in Dantu+ membranes and the minor component J (molecular mass 22 KDa) occurring in normal and Dantu+U+ GP preparations, but not in those from Dantu+U- cells, has not been resolved. The apparent molecular mass of the anion channel protein (band 3) in all cells of the NE variety was shown to be decreased by about 3 KDa, due to a shortening of carbohydrate chains. This suggests that the hybrid, just like GP A, might form a complex with band 3.

Alleles

Characterization of the Ss sialoglycoprotein and its antigens in Rhnull erythrocytes.

The Ss sialoglycoprotein (glycophorin B) and its antigens in Rhnull erythrocytes, which lack the Rhesus blood group antigens, due to apparently silent (amorphic type) or independent suppressor (regulator type) genes, were investigated. The quantity of the molecule in amorphic and in regulator type red cell membranes was found to be decreased by about 60%-70%, as judged from sodium-dodecylsulfate polyacrylamide gel electrophoresis. The Ss glycoprotein content in the erythrocytes from heterozygotes (regulator type) was diminished to an extent of about 30%. Confirming and extending previous studies, the S, s, Ux, Uz and 'N' antigens were slightly weakened in Rhnull erythrocytes. The U and Duclos receptors were only slightly or not depressed in amorphic Rhnull cells, but almost absent from or not detectable in those of the regulator type. This demonstrates that an additional alteration, apart from the decreased Ss glycoprotein content of the membranes, accounts for the weakness of these receptors in regulator type cells. We propose the hypothesis that (a) protein(s) encoded by the Rhesus locus form(s) a complex with the Ss glycoprotein. Thus, it (they) might facilitate the incorporation of the Ss glycoprotein into the membrane and also contribute to the complete expression of the U and Duclos antigens in normal cells.

Densitometry

Swa: a subdivision.

For some time, anomalous serological reactions have been observed when the same anti-Swa sera are tested against red cells from different individuals reported as Sw(a+). A comparative collaborative study using the same collection of Sw(a+) cells and anti-Swa sera was undertaken by 4 reference laboratories, and it was found that Swa represents a heterogeneous group of antigens that can be subdivided into two categories. Both categories, Sw(a+) 700:41 and Sw(a+) 700:-41, were shown to be inherited.

Blood Group Antigens

Altered membrane sialoglycoproteins in human erythrocytes lacking the Gerbich blood group antigens.

The sialoglycoproteins (glycophorins) in human red cell membranes of rare individuals lacking totally (Ge-1,-2,-3 phenotype) or partially (Ge-1,-2,3 phenotype) the Gerbich (Ge) blood group antigens and two Ge-1,-2,-3 heterozygotes were studied by dodecylsulfate polyacrylamide gel electrophoretic techniques. Two sialoglycoproteins (components D and E) were not detectable in the membranes from the homozygotes and found to be decreased by about 50% in those from the heterozygotes. Ge--1,-2,-3 and Ge-1,-2,3 cells were found to contain a 'new' component (mol. masses about 29 and 30 kDa, respectively) possibly representing a D/E hybrid molecule. This sialoglycoprotein was not detectable in membranes from the Ge-1,-2,-3 heterozygotes, suggesting that the Ge-1,-2,-3 phenotype may be caused by at least two different alleles at the Ge blood group antigen locus. Hemagglutination or hemagglutination inhibition tests involving anti-Ge 1,2,3 and -Ge 1,2 as well as native and enzyme-treated normal red cells (phenotype Ge 1,2,3) or membrane and sialoglycoprotein fractions from normal erythrocytes indicate that the receptors of these sera are located within the glycosylated domain(s) of the D and/or E sialoglycoprotein(s). Our data suggest that the Ge locus encodes the polypeptide sequences of the D and E sialoglycoproteins.

Blood Group Antigens

High frequency antigens of human erythrocyte membrane sialoglycoproteins. I. Ena receptors in the glycosylated domain of the MN sialoglycoprotein.

The specificity of various allo- and autoantibodies, which agglutinate normal erythrocytes, but do not react with En(a-) red cells and normal erythrocytes, treated with trypsin (anti-EnaTS) or ficin (anti-EnaFS), was investigated. Various fragments and modification products of the major (MN) red cell membranes sialoglycoprotein were used in hemagglutination inhibition assays. Six anti-EnaFS sera were found to be directed against the residues approx. 46-56 of the molecule. Five of these require the carbohydrate unit, attached to Thr50, for binding. One anti-EnaTS serum was found to be directed against the residues approx. 36-42. Another antibody with anti-EnaTS specificity was shown to react with the residues 31-39 in some of the MN sialoglycoprotein molecules, namely those not glycosylated at a certain position (probably Thr33). A third anti-EnaTS serum, directed against the sequence domain around Lys30, was also found to react only with a fraction of the molecules, apparently due to the variable attachment of oligosaccharides in that region. The heterogeneity of glycosylation, detected by these two sera, appears to account for the partial tryptic and chymotryptic cleavage in this domain of the MN sialoglycoprotein, which has been described previously. Heterogeneity of the glycosylation at various positions of the molecule could be established by the isolation and analysis of peptides.

Amino Acid Sequence

Cold agglutinins in infectious mononucleosis and heterophil-antibody-negative mononucleosis-like syndromes.

Cold agglutinins (CA) were evaluated prospectively in patients with various mononucleosis syndromes and in a large control group. Cold agglutinins with anti-i specificity were seen mainly in heterophil-positive or -negative Epstein-Barr virus (EBV)-induced infectious mononucleosis (31.8% of cases). Unclassified CA with equal reactivity against cord and adult erythrocytes were seen in 56 of 150 (37.3%) cases of heterophil-antibody-positive infectious mononucleosis (IM), in 1 of 7 (14.3%) cases of heterophil-negative EBV-induced IM, and in 12 of 31 (38.7%) cases of the heterophil-negative mononucleosis-like syndrome due to cytomegalovirus or other unspecified agents. One patient with heterophil-positive IM had a persistent, partially papain sensitive CA with anti-Pr-like activity. Anti-i CA were seen in less than 1.0% of healthy young adults (500) or patients without mononucleosis (500) submitted for heterophil studies. Unclassified CA were noted in 3.2% of the latter 1000 samples.

Agglutinins

A clinical study of anti-NDP in the sera of patients in a large repetitive hemodialysis program.

Anti-NDP has been detected in the sera of 38 of 430 patients on regular hemodialysis at the Regional Kidney Disease Program in Minneapolis. It developed in these patients from 7 to 58 months after commencement of dialysis. Bacterial infection appeared temporally related to the development of anti-NDP in 12 patients. Hemolytic episodes, possibly related to anti-NDP, occurred in 11. Fifty-five percent of the patients never reused dialyzers. The antibody preceded the insertion of a bovine graft in seven. We postulate that anti-NDP is recognizing an antigenic site similar to that recognized by Vicia graminea lectin, and that this site might become immunogenic by alteration of M and N antigens on red blood cell surfaces. Though formaldehyde might be involved in this alteration, dialysis membrane reuse does not seem to be required for the formation of anti-NDP.

Adult

Hemolytic anemia caused by auto anti-N.

The second case of hemolytic anemia caused by auto anti-N, occurring in a 7-year-old boy, is described. The antibody was IgG, as shown by the use of specific anti-human IgG Coombs sera, failure of inactivation by 2-mercaptoethanol, and chromatographic separation on a G-200 Sephadex column.

Anemia, Hemolytic, Autoimmune

Anomalous inheritance of Ss in a Caucasian family.

An unusual allele at the Ss locus with no S or s antigenic representation was found in 3 generations of a Caucasian family. Traveling with N, this genetic determinant was detected because of an apparent maternal exclusion.

Alleles

A new antigen, McCa (McCoy), and its relationship to Kna(Knops).

The antigen McCa is detected in 98.5 and 96.7 per cent of the American Caucasian and Negro populations respectively. In population studies with anti-McCa and anti-Kna, a strong association was demonstrated between the two antigens, with 53 per cent of McC(a-) sample being Kn(a-) compared with a reported frequency for Kn(a-) of only 0.19 per cent.

Adult