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R Oriol

Publications and source records attributed to R Oriol.

At least 181 records · Page 10Linked to original sources
PubMed1980

Distribution of blood group antigen A in normal and pathologic human kidneys.

We tested this distribution with an indirect immunofluorescent technique using purified rabbit anti-A antiserum on 21 whole normal kidneys (a group, N equal to 18; AB group, N equal to 1; O group, N equal to 2) and on 349 kidney biopsy samples (A group, N equal to 140; AB group, N equal to 14; O or B group, N equal to 195) representing a large spectrum of renal diseases. In normal kidneys from A and AB groups, the A antigen was detected in the whole vascular endothelium and in the convoluted distal tubules. In secretors, collecting tubules were brightly positive. Epithelial staining was more diffuse in the inner part than it was in the outer part of the medulla. The basement membrane of the inner collecting tubules was positive in frozen sections but not in paraffin sections. In pathologic kidneys, modifications were obvious: (1) The thickened basement membrane of atrophic convoluted distal tubules was brightly stained. (2) Endothelial staining allowed a precise appreciation of the glomerular and interstitial vasculature. (3) In proliferative changes such as arterial intimal proliferation, proliferative glomerulonephritis, and interstitial cell infiltration, endothelial cells do not proliferate. This routine staining technique of endothelial cells by anti-A antiserum provide information not obtainable with light microscopy.

ABO Blood-Group System↗
PubMed1980

Combined effects of HLA matching and age in renal transplantation.

Recipient age and matching for the HLA-A and B antigens each influence the graft survival rate of cadaver kidney transplants by approximately 10%. These two factors are cumulative and have a combined effect of nearly 20%. Thus, other factors that have a relatively weak influence on graft success may have a combined effect that makes their clinical consideration highly relevant.

Adolescent↗
PubMed1980

The Lewis system and kidney transplantation.

A significant effect of Lewis antigens on cadaver kidney graft survival was found in 1,300 North American transplants. Lewis-negative recipients had a graft survival rate that was 8% lower than that of Lewis-positive recipients (P = 0.05). This effect of Lewis antigens was enhanced in patients at a high failure risk as determined by age, race, or transplant center. In patients older than 30 years, the effect of Lewis was 14% (P = 0.07), in non-Caucasians 12% (P = 0.07), in all grafts performed at centers with less than 50% overall 1-year graft survival 12% (P = 0.03), and in non-Caucasians that received transplants in centers with less than 50% overall graft survival it was 18% (p = 0.01). These data confirm previous results on the role of Lewis as a histocompatibility system in renal transplantation; furthermore, they demonstrate that the influence of Lewis is larger in patients at high risk.

Adult↗
PubMed1979

ABH and Lewis antigens on lymphocytes: screening of pregnant women's sera with the B-cell cytotoxicity test.

Five phenotypes related to the ABH-Lewis substances were defined by the B-cell lymphocytotoxic test. These five antigens are built up in a stepwise fashion by the action of the glycosyl transferases specified by the Le, H, and the A, B genes onto the same ABO percursor molecules. The comparison of their chemical structures with the cluster analysis obtained by cytotoxicity suggests that antibodies reacting with large antigenic structures (pentasaccharides) have a more restricted specificity than antibodies reacting only with smaller antigenic determinants (trisaccharides).

ABO Blood-Group System↗
PubMed1978

The Lewis system: New histocompatibility antigens in renal transplantation.

Lewis antigen types (Le, le) were retrospectively determined in 255 first-kidney-transplant recipients. Actuarial survival of grafts at two years was significantly lower in the le/le recipients than in the Le recipients. This indicates that mismatching of these antigens contributes to rejection of kidney transplants. The effects of mismatching for the Lewis and HLA antigen systems seemed to be additive.

Epitopes↗
PubMed1977

[Role of the Lewis (Le-le) and secretor (Se-se) systems in the rejection of kidney grafts].

ABH and Lewis antigens are secreted in distal convoluted and collector tubes of the kidney. The renal ABH secretion is genetically controlled by the Se-se system, while the Lewis specificities are controlled by the Le-le system. The secretory status of the recipient does not modify the probability of graft survival, while the Lewis phenotype seems to play a major role in rejection. The probability of graft survival at 2 years in le-le homozygous recipients (29%) is much lower than that of Le recipients (58%) p less than 0.01.

ABO Blood-Group System↗
PubMed1977

Radioimmunoassay of the WZ polymorphic antigens of normal human colon and their relationship with ABH antigenic determinants.

Heat resistant, high mol. wt glycoproteins of the three WZ phenotypes (W+Z+, W-Z+ and W-Z-) were extracted from normal human colonic mucosa and labelled with 125I. More than 80 per cent of the radioactivity of the W+Z+ antigens labelled with I125, was precipitated by natural or immune anti-W antibodies. About 60 per cent of the W-Z+ 125I-labelled antigens were precipitated by immune anti-Z antibodies. No specific precipitation could be detected with W-Z- 125I-labelled antigens. All the precipitin reactions were quantitatively inhibited with the crude antigen extracts of the corresponding phenotypes. The W and Z antigens were only found in the intestinal mucosa and there was a 100-fold increase in the relative concentrations between the small bowel and the rectum. As opposed to this, the ABH antigens were found in all the digestive secretions studied, except those of the rectum, and their relative concentrations progressively decreased by about 100 between the small intestine and the recutm. The decrease in ABH concentration seems to be correlated to a WZ increase in the same regions.

ABO Blood-Group System↗
PubMed1977

Differences in the maturation of the immune response of A- and A+ rabbits. Good and poor responders respectively for the A antigen.

The amount, avidity and specificity of anti-A antibodies produced by rabbits having the A substance in their secretions (A+) and rabbits lacking this antigen (A-), were studied with a series of antigens chemically related to the A substance. Both A- and A+ rabbits produced specific anti-A antibodies but the amount, maturation of avidity and specificity of these antibodies was completely different. These results suggest that the difference between the immune response of A+ and A- animals is not based on a genetically determined inability of A+ rabbits to recognize the self antigen, but rather on differences in the regulatory mechanism(s) controlling the maturation process of the anti-A response.

Animals↗
PubMed1976

Immunological response to experimental echnococcosis in Meriones unguiculatus.

Varying doses of protoscolices of Echinococcus granulosus were injected intraperitoneally into Mongolian jirds, Swiss mice, and golden hamsters. After 4 months the animals were killed and the numbers of developing cysts counted. Jirds were by far the most susceptible hosts. Doses of 500 protoscolices produced 100% infection rates in both weanlings and adults. Comparable infection rates in weanling mice required inocula of 5,000 protoscolices, but even at this dose hamsters were refractory to infection. Three of 5 jirds developed pulmonary cysts after intravenous administration of 500 protoscolices. Serologic responses in infected jirds were followed using the indirect hemagglutination tests and a purified fraction of hydatid cyst fluid (HCF) as antigen. Titers reached a plateau after 15 weeks and were maintained for several months. Much brisker serologic responses occurred in animals sensitized with the antigenic fraction in various adjuvant vehicles. At no time during infection did jirds show any evidence of immediate hypersensitivity to HCF in direct skin tests, passive cutaneous anaphylactic tests, or after intravenous challenge with antigen. After artificial immunization with hapten-conjugated antigens or HCF, jirds underwent a fatal shock following intravenous challenge with antigen. HCF provoked the appearance of circulating antibodies which were capable of sensitizing normal recipients for passive systemic anaphylaxis after a latent period of 72 hr. It is concluded that the failure of the infected jird to develop immediate hypersensitivity responses to E. granulosus represents a marked deviation from the parrern of the immune response in echinococcosis in man and domestic animals and must be considered in the future use of this animal in experimental studies on the host-parasite relationship.

Animals↗
PubMed1975

An IgM Waldenström with specificity against phosphorylcholine.

Anti-phosphorylcholine specificity has recently been shown to occur with relatively high incidence among IgA myeloma proteins secreted by oil-induced plasma cell tumors in the BALB/c strain of mice. A similar screening of human myeloma sera indicates that in man activity for phosphorylcholine is very rare. Among 904 human sera containing IgG, IgA, and IgM M-components only one reacted with phosphorylcholine-containing antigens. This serum was obtained from a patient with macroglobulinemia Waldenström. The active homogeneous protein could be isolated by affinity chromatography using a Sepharose-phosphorylcholine immunoadsorbent. It was an IgM immunoglobulin; the light chains were of the kappa type. The association constant for the reaction with phosphorylcholine was homogeneous and equalled 6.4 times 10-4 l. mol-1 at 25 degrees and 8.1 times 10-4 l. mol-1 at 2 degrees, indicating that the binding reaction is exothermic. The valences of the pentamer IgM, the 7S IgM subunit produced by reduction with cysteine, and the Fab fragment obtained by cleavage with papain were 10, 2, and 1, respectively. By all criteria available for antibody-like binding such as high specificity, restriction of the binding sites to the Fab part of the molecule and correct stoichiometry this IgM exhibits the fundamental characteristics associated with conventionally induced antibodies.

Aged↗
PubMed1975

Bispecific cells among IgM and IgG producers during the early phase of primary and secondary responses.

Simultaneous immunization of mice with sheep (SRBC) and horse (HRBC) erythrocytes regularly resulted in the appearance of hemolytic plaque-forming cells (PFC) specific for each type of erythrocyte and also of PFC lysing both types of erythrocytes. After primary stimulation the highest number of bispecific cells (42/10(6) cells) was found among PFC as revealed by the direct procedure (IgM producers). Among PFC enhanced with anti-mouse Fab serum (IgG producers), bispecific cells were less numerous (8/10(6) cells). In preparations enhanced by anti-mouse-gammaFc serum which reveals IgG producers without inhibiting IgM antibody, the number of bispecific PFC equalled the sum of bispecific cells revealed by direct and anti-Fab enhanced procedures. The number of direct bispecific PFC during primary and secondary response was approximately the same, whereas the number of IgG-producing, bispecific PFC increased considerably during the secondary response. Another difference was the time limitation of the appearance of bispecific cells: after primary immunization direct bispecific PFC were detected only on days 3, 4 and 5, but enhanced bispecific PFC were present from day 4 up to day 12. However, during the secondary reaction, bispecific PFC were detected by all three procedures only between days 3 and 6. Studies on the cross-reactivity between SRC and HRBC gave negative results at the humoral level, even when the mice were primed with a minimal amount of both erythrocytes and then two months later, boosted with one of them. Studies at the cellular level showed that after immunization with one antigen, only 0.4 to 0.7 direct or enhanced PFC/10(6) cells could simultaneously lyse both erythrocyte types. Thus, a hundred times more bispecific PFC were constantly found after double immunization of the animals. Moreover, sudden disappearance of all bispecific PFC on the 7th day after secondary stimulation makes it unlikely that all bispecific PFC are simply cross-reacting cells.

Animals↗
PubMed1975

Definition in man of a polymorphic system of the normal colonic secretions.

A study conducted in 30 normal human colons, obtained from cadaveric kidney donors, has evidenced the presence of two polymorphic antigenic specificities, W and Z, in the secretory cells of the colon mucosa. Three phenotypes have been demonstrated so far: W-Z- (frequency: 0.17), W-Z+ (frequency: 0.23), and W+Z+ (frequency: 0.60). Specific anti-WZ and anti-W alloantibodies, independent of anti-A and B agglutinins, were found in normal sera from blood donors. No apparent correlation was found between the WZ specificities and the ABH Lewis specificities, the other blood group systems specificities, and the leucocyte group (HL-A) specificities.

Blood Group Antigens↗
PubMed1975

Physiocochemical properties of a lipoprotein antigen of Echinococcus granulosus.

Molecular weight and optical properties of the lipoprotein B, the main antigen produced by the parasite in sheep hydatid fluid, have been determined. By sedimentation equilibrium studies, its molecular weight has been found equal to 120,000. Circular dichroism and optical rotatory dispersion spectra are consistent with an alpha-helix content of about 50%, and this ordered structure is not completely destroyed by dissociation in guanidinium choloride. The ORD spectrum is discussed in relation to the biological function of the lipoprotein antigen.

Animals↗
PubMed1975

Statistical study on double paraproteinemias. Evidence for a common cellular origin of both myeloma globulins.

Double paraproteinemias (DPP) are usually considered as resulting from a proliferation of two independent clones of cells. The present study describes a statistical analysis based on 141 published cases of DPP. The incidence of the heavy chain classes as well as of light chain types association has been compared with the frequency of occurence of the same H and L chains in simple paraproteinemias. Computation of the frequency of associations showed that different heavy chains are randomly associated in DPP. However, light chains are more frequently of the same type in both immunoglobulins more so than could be expected on the basis of a biclonal hypothesis (p less than 0.005). This preferential occurence of identical light chains suggests a linkage in the synthesis of two proteins and it favours a monoclonal origin of myeloma cells in DPP.

Humans↗