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P D Issitt

Publications and source records attributed to P D Issitt.

At least 109 records · Page 6Linked to original sources
PubMedDate not supplied

An antibody that recognizes a determinant common to S and s-bearing sialoglycoproteins.

We describe an antibody, made by an individual of the phenotype M+, N+, S+, s+, U+, that reacted only with ficin or papain-treated red blood cells, and that initially appeared to have anti-S specificity. However, further studies revealed that the antibody, which did not have anti-U specificity, recognized a determinant present on S+, s-, U+, and S-, s+, U+, but missing from S-, s-, U-, and S-, s-, U+, red blood cells. The specificity of this antibody is discussed in terms of current knowledge of the structure of the Ss sialoglycoprotein.

Aged↗
PubMedDate not supplied

Studies on the blood of an MiV/Mk proposita and her family.

An individual (J-1) was shown to be heterozygous for the MiV and Mk genes. Her red cells typed as M+(weak), N-, S-, s+(strong), U+, Hil+, Wr(a-b-), En(a+weak). Polyacrylamide gel electrophoresis analysis of her red cell membranes revealed absence of PAS-staining bands corresponding to normal MN and Ss sialoglycoprotein (SGP), and presence of a hybrid MNSs SGP [(alpha-delta)MiV] similar but not identical to that reported for an MiV homozygote. However, J-1 cannot be homozygous for MiV since the red cells of two of her children are Hil- and s-, carry only a single dose of M antigen, and have a sialic acid content that is consistent with the presumption that they are Mk heterozygotes. J-1's hybrid MNSs SGP is considered to be gene-fusion product resulting from unequal crossover between a normal alpha M and delta gene, and her red cells lack that portion of the Ena antigen that is resistant to ficin. Her hybrid MNSs SGP differs, therefore, from that reported for the MiV homozygote, which probably arose from unequal crossover between alpha N and delta genes. Further, the red cells of the MiV homozygote carry the ficin-resistant Ena determinant.

Aged↗
PubMedDate not supplied

Further studies on the dependence of some examples of anti-M and anti-N on the presence of red-cell-borne sialic acid.

Previous studies have shown that some examples of anti-M and anti-N fail to agglutinate neuraminidase-treated (NeuNAc-depleted) red cells. This investigation extends those observations and shows that the antibodies fail to bind to such treated red cells. These observations may mean that NeuNAc residues act to orient the protein portion of the MN sialoglycoprotein so that it is recognized by the antibodies. Alternatively, it is possible that NeuNAc residues are an integral part of the antigen defined.

Binding Sites, Antibody↗
PubMedDate not supplied

The M1 and Tm antigens require M and N gene-specified amino acids for expression.

It is known that the major red cell sialoglycoprotein (SGP) of M1 + red cells has the same amino acid sequence as M SGP, whereas that of Tm + cells has the same sequence as N SGP. M1 and Tm are serologically demonstrable when a substitution of N-acetyl-D-glucosamine for N-acetyl-neuraminic acid occurs in one or more of the alkali-labile tetrasaccharides bound at positions 2, 3, and/or 4 of M or N SGP, respectively. The authors used two serums containing anti-M and potent anti-M1 and two containing anti-Tm in tests for antibody crossreactivity and cross adsorption and in antibody inhibition studies. The distinct specificities of anti-M1 and anti-Tm, as determined by these studies, show that the M and N gene-specified amino acids are more important than the glycosylation change in the fine structure of M1 and Tm antigens.

Acetylglucosamine↗
PubMedDate not supplied

Donath-Landsteiner hemolytic anemia due to an anti-Pr-like biphasic hemolysin.

Anemia, hyperbilirubinemia, and reticulocytosis subsequent to viral infection were present in a 32-year-old woman. The direct antiglobulin test was negative, and no unexpected antibodies were detected in pretransfusion tests. Rosettes of red cells (RBCs) around neutrophils were observed in peripheral blood smears, and a Donath-Landsteiner (D-L) test was positive. However, the patient did not show the classic features of paroxysmal cold hemoglobinuria (PCH). There was no hemoglobinuria, and in vivo hemolysis was not precipitated by cold. The D-L antibody was IgG, but classic anti-P specificity was not apparent. Rather, protease- or neuraminidase-treated RBCs, as well as certain sialic acid deficient RBCs of uncommon MN phenotypes, were not hemolyzed in D-L tests. Further, D-L antibody activity could be inhibited by MN sialoglycoprotein. These data support a diagnosis of chronic D-L hemolytic anemia, caused by an anti-Pr-like biphasic hemolysin.

Adult↗
PubMedDate not supplied

Anti-Rh33, the second separable example, also made by a person who made anti-D and has C+ red cells.

A complex serologic investigation resulted in identification of the second example of separable anti-Rh33. A patient who had been transfused frequently and who had red cells that lacked a portion or portions of the D mosaic of antigens made anti-D against that portion of D missing from her red cells, anti-c, anti-V, anti-Rh33, anti-K, and an autoantibody that mimicked the reactions of anti-D. Differential adsorption experiments showed that the anti-Rh33 was separable from the other antibodies present. The serologic findings in this case and in the study in which anti-Rh33 was first found show some sort of relationship between D and Rh33. First, one of the genes, RoHar, that makes Rh33 makes a form of D that is difficult to detect. Second, the only other gene thus far known to make Rh33, DIV (C)-, encodes for a form of D from which portions of the D mosaic are missing. Third, both examples of separable anti-Rh33 were made by women who made anti-D and whose red cells were C+.

Blood Grouping and Crossmatching↗
PubMedDate not supplied

Evidence that Wra and Wrb are antithetical.

Studies on 24 Wr(a+b+) and 23 Wr(a-b+) blood samples, using anti-Wrb in the enzyme-linked antiglobulin test (ELAT), have shown that Wr(a+b+) red cells bind, on average, a little over half the amount of anti-Wrb bound by Wr(a-b+) red cells. Similarly, ELAT studies using six different anti-Wra and 10 Wr(a+b+) samples, as well as red cells from the original Wr(a+b-) proposita, have shown that Wr(a+b+) red cells bind about half the amount of anti-Wra bound by Wr(a+b-) red cells. Various pitfalls that can arise when the ELAT is used to measure antigen ratios on red cells have been avoided but are described. This conclusive evidence that Wra and Wrb have an antithetical relationship is discussed in light of the knowledge that a ficin-resistant portion of MN sialoglycoprotein (SGP), when carried in liposomes, can inhibit anti-Wrb. It is possible that Wra, Wrb, or both may encode a post-translational change in MN SGP, or production of transferases that glycosylate membrane lipids that affect in situ orientation of MN SGP, or production of protein band 3 that then forms a complex with MN SGP at the red cell membrane surface.

Antibodies, Anti-Idiotypic↗
PubMedDate not supplied

Studies on the blood of a Dc(e) homozygote and her family.

It has been reported previously that genes that have been called Dc- represent a heterogeneous group and that some of them would better be described as Dc[e] and Dc(e). We have studied the blood of a black proposita and some of her family members and have concluded that she is homozygous for Dc(e). The form of Dc(e) present in this family makes all the Rh antigens of common occurrence for which we were able to test. In this respect, it differs markedly from another form of Dc(e), which is seen in individuals whose red cells lack a very common Rh antigen and who become immunized against that antigen. We suggest the term Dc(e)R17 for the gene present in the family studied; our results indicate that its products are: normal amounts of D, c, G, Hr0, and Rh29; reduced amounts of e and f; and markedly reduced amounts of hrS and hrB. The expression of some antigens encoded by Dc(e)R17 are quantitatively but not qualitatively different from the products of R0.

Blood Grouping and Crossmatching↗
PubMedDate not supplied

Heterogeneity of anti-U demonstrable by the use of papain-treated red cells.

When red cells (RBCs) are treated with papain, one form of the U antigen, which we have named UPS (U papain-sensitive), is almost completely removed or denatured. A second form, UPR (U papain-resistant), remains unaltered on the treated RBCs. Tests on 42 examples of anti-U showed that two contained only anti-UPS, 19 contained only -UPR, and 21 contained separable -UPS and -UPR. In those sera containing both antibodies, anti-UPR was always the stronger of the two. These findings suggest 1) that UPS is located on the Ss sialoglycoprotein (glycophorin B) at a position distal to a papain-sensitive site or that the cleavage point is within the portion of the SGP that comprises UPS, and 2) that UPR is located between the papain-sensitive site and the RBC membrane. The UPS determinant was not denatured by neuraminidase, L-cysteine, trypsin, ficin, or alpha-chymotrypsin, and it was only partially denatured by pronase. The finding that RBCs treated with para-chloromercuribenzoic acid or para-chloromercuriphenyl sulfonic acid did not react with anti-UPR but did continue to react with anti-UPS suggests that the in situ configuration of UPR, but not UPS, is dependent on the presence of one or more disulfide bonds. RBCs of the S-s-U+(weak) phenotype were shown to carry markedly reduced amounts of both UPS and UPR.

Adsorption↗
PubMedDate not supplied

In vivo red cell destruction by anti-Lu6.

An example is presented of an IgG1, anti-Lu6, that reacted by indirect antiglobulin test and was capable of destroying antigen-positive red cells in vivo. Two methods for the measurement of red cell survival, 51Cr labeling and flow cytometry, gave the same result: 20 percent of the test dose of Lu:6 red cells was destroyed in the first hour after injection and 80 percent in the first 24 hours. The clinical relevance of the antibody was correctly predicted by an in vitro monocyte monolayer assay. The finding that this example of anti-Lu6 was clinically significant should not be taken to mean that all antibodies directed against high-incidence Lutheran and Lutheran system-related antigens will behave similarly. When such antibodies are encountered, in vivo and/or in vitro studies to assess their clinical significance are necessary before rare blood is used for transfusion.

Aged↗
PubMedDate not supplied

Inhibition of an anti-Pr1d cold agglutinin by citrate present in commercial red cell preservative solutions.

A patient with known cold autoimmune hemolyticanemia was admitted for surgery. Routine cold agglutinin evaluations, using commercial red cells (RBCs) in modified Alsever's preservative solution, revealed a cold agglutinin titer of 4 to 16. However, using RBCs washed four times with saline, a high-titer (greater than 2000 at 4 degrees C) cold autoagglutinin was demonstrated. The cold agglutinin was shown to be an IgM kappa paraprotein with anti-Pr1d specificity. The addition of Alsever's solution to washed RBCs inhibited the cold agglutinin. Each major component of Alsever's solution (neomycin, chloramphenicol, inosine, dextrose, and citrate) was tested individually; only citrate inhibited the patient's cold agglutinin. Various compounds structurally related to citrate were tested and found to cause various degrees of inhibition. The strongest inhibition correlated with the presence of either three carboxyl groups on molecules devoid of double-bonded carbon atoms or two carboxyl groups in cis configuration. A panel of 54 cold agglutinins, including 7 with anti-Pr specificity, was analyzed. None was significantly inhibited by Alsever's solution, although one with anti-Pr2 specificity was weakly inhibited. In summary, these studies describe an anti-Pr1d cold autoagglutinin that was inhibited by citrate in RBC preservative solutions. The failure to detect such a cold agglutinin can result from not washing RBCs free of citrate before testing.

Aged↗
PubMedDate not supplied

JMH variants: serologic, clinical, and biochemical analyses in two cases.

BACKGROUND: JMH is a high-frequency red cell blood group antigen that resides on a 76- to 80-kDa glycosylphosphatidylinositol-linked protein also known as CDw108. Antibodies with JMH specificity are often autoimmune and are usually, if not always, clinically benign. Some individuals with JMH-variant antigen produce alloantibodies to JMH, but little evidence concerning their clinical significance is available. This article reports on two patients who express a JMH-variant antigen and produced alloanti-JMH. STUDY DESIGN AND METHODS: Murine monoclonal antibodies and human antibodies to JMH were used in hemagglutination, radioimmunoassay, and Western blot testing of red cells from two JMH-variant patients; antiserum from one of these patients was also used in biochemical studies. In addition, in vivo survival of JMH-positive red cells was studied in the same patient. RESULTS: Biochemically, both examples of red cells with the JMH-variant phenotype expressed a JMH protein with a molecular weight similar to that of the normal JMH protein. For both patients, family studies suggested an autosomal recessive pattern of inheritance. Survival study demonstrated reduced in vivo red cell survival in one patient. CONCLUSION: JMH-variant phenotypes express a protein of normal molecular weight and are inherited in an autosomal recessive pattern. Furthermore, individuals with this phenotype can produce clinically significant antibodies.

Aged↗