PubMed HealthSearch

Biomedical subjects

M Lopez

Publications and source records attributed to M Lopez.

35 records · Page 2Linked to original sources

An unusual Rh phenotype indicating heterogeneity of the Cw antigen.

A family is reported in which a new Cw antigen occurred in two generations. This was recognized by 17 anti-Cw sera, but by none of the 21 anti-C sera which were, however, shown to react strongly with common Cw+ cells. This unusual finding provides evidence that the Cw antigen is in fact heterogeneous. On the basis of data obtained from absorption-elution and coagglutination studies a tentative explanation is attempted: common Cw+ phenotypes are assumed to be Cw (+1+2) and the present phenotype Cw (+1-2). Anti-Cw sera should accordingly be anti-Cw1, whereas anti-C sera should only react with Cw2.

Antigens, Heterophile

An immunological investigation of a family with chronic mucocutaneous candidiasis.

Chronic mucocutaneous candidiasis in two siblings of consanguineous parents suggested an autosomal recessive transmission of the disease. We evaluated the two affected persons and 21 members of their kindred for an inherited immunological defect. Six members of the kindred, including both patients, had negative skin-delayed hypersensitivity to Candida. The lymphocytes of both patients and three asymptomatic relatives had diminished in vitro blastogenic response when cultured with Candida albicans. Because the defect occurred in clinically unaffected relatives, we concluded that the lack of blastogenic response to C. albicans was not the only determinant for or may be unrelated to the clinical manifestations of the disease.

Antigens

Polyagglutinability associated with the cad antigen.

Various anti-Cad and anti-Sda reagents were tested against a panel of Cad red cells in order to determine whether Cad and Sda antigens were identical. According to the results, although strong Sda reactivity was always found in Cad red cells, the two antigen specificities are not identical. The polyagglutinability of Cad red cells seems to be related to an anti-Cad present in all human sera but Cad, and not with anti-Sda antibody.

ABO Blood-Group System

Jk(a-b-) phenotype in a French family. Quantitative evidence for the inheritance of a silent allele (Jk).

A Caucasian French family was investigated including two Jk(a-b-) sibs who had developed anti-JkaJkb. The parents were first cousins. Quantitative study of Kidd antigens using titration scoring and HD50 assay clearly showed the parents and a maternal aunt, phenotypically Jk(a+b-), to have a weak expression of Jka documenting thereby the transmission of the postulated silent gene Jk. Absorption, elution and coagglutination assays revealed the cross reactivity of the antibody developed by the two sibs. Leucocytes and platelets from these two individuals were not shown to absorb anti-JkaJkb.

Alleles

Cis AB blood groups. Immunologic, thermodynamic and quantitative studies of ABH antigens.

Fifteen samples of cis AB bloods belonging to six unrelated families were tested by serological and thermodynamic assay techniques. The B and H antigens of cis AB bloods differ significantly from those of trans AB bloods. Differences were found among unrelated samples, but identical results were obtained within a given family : this could mean that there had been as many mutations as there were families.

ABO Blood-Group System

Incidence of serum anti-DNA precipitins in patients with systemic lupus erythematosus by counterimmunoelectrophoresis.

The technique of counterimmunoelectrophoresis (CIE) has been adapted for detection of serum precipitins to calf thymus (CT) DNA in patients with SLE, discoid LE, miscellaneous connective tissue and infectious diseases, and control populations. Of seventy-eight LE patients, 58% demonstrated anti-ss DNA precipitins, and 20% exhibited anti-ds DNA precipitins. Good correlation was noted between the presence of ss DNA precipitins and ss DNA binding values determined by the more sensitive ammonium sulphate precipitation assay. Depressed total serum haemolytic complement activity in CH50 mu/ml was noted in 64% of sera exhibiting ss DNA precipitins and 38% of those with negative ss DNA precipitins. There was a strong association, however, between ds DNA precipitins and depressed serum complement levels. Although less sensitive than primary binding assays, CIE can be used as a rapid and simple screening test for detection of circulating anti-native and denatured CT DNA precipitins. CT DNA serum precipitins are present in a significantly higher percentage of SLE patients when compared with other disease states and normal control populations.

Ammonium Sulfate

Agglutination kinetics. A method for quantitative red cell antigen assays.

A simple, sensitive and highly reproducible method is described using a particle counting procedure for the study of agglutination percentage of red cells as a function of time. The method may advantageously be used for the current study of zygosity and other antigenic variations especially in family investigation.

Erythrocyte Count

Numbers of Giardia in the feces of infected children.

Estimates were made of the number of Giardia in 1,090 stools from 15 infected children over periods of 1 to 3 months. Three patterns of excretion were observed: 1) high, with the parasite abundant in nearly all stools; 2) low, with the parasite detectable in only 40% of the stools and scanty when present; and 3) mixed, with periods of 1 to 3 weeks of high excretion alternating with generally shorter periods of low excretion, and an overall average of about 60% of stools positive. The presence and relative numbers of Giardia in the feces apparently were unrelated to either the consistency of the stools or frequency of defecation. Attempts to increase parasite excretion with purgatives were, on the whole, unsuccessful.

Carrier State

Quantitative and thermodynamic studies of erythrocytic ABO antigens.

This paper presents recent data from quantitative and thermodynamic investigations on A and B erythrocyte antigens. In regard to weak A phenotypes on the basis of quantitative data, practically no gap is observed from the weakest Aend to the strongest A3. Weak B phenotypes give a similar distribution. However, a more precise structural analysis including kinetics and thermodynamic measurements provides convincing evidence for the heterogeneity of each type of weak B reactive structures. Weak B antigens appear to be different from one to another, but similar inside one family. However, thermodynamics failed to demonstrate a qualitative difference between the weak B antigen in BX groups and the enhanced B antigen in ABX heterozygote, phenomenon that occurs in some very rare families. The same data were obtained from kinetic and thermodynamic analysis of B reactivity in cis AB samples; it can be assumed that such mutants are all different.

ABO Blood-Group System