Morris Reichlin

Correlation of a Precipitin Reaction to an RNA-Protein Antigen and a Low Prevalence of Nephritis in Patients with Systemic Lupus Erythematosus

Abstract A group of patients with systemic lupus erythematosus had in their serums precipitating antibodies to a soluble nuclear ribonucleoprotein antigen, a low frequency of complement-fixing antibodies to single-stranded DNA, and a paucity of serious renal disease. As in other reported series, a positive relation was found between the presence of complement-fixing antibodies to single-stranded DNA and the frequency of nephritis. In their nonrenal clinical manifestations the patients with antibodies to the RNA-protein antigen resemble others with systemic lupus erythematosus, but as might be expected from the low prevalence of nephritis, their prognosis thus far appears favorable.

ANTIBODIES TO HUMAN A1 HEMOGLOBIN AND THEIR REACTION WITH A2, S, C, AND H HEMOGLOBINS.

Abstract Antibodies with specificity toward A 1 human hemoglobin have been produced in rabbits. The antisera were identified as anti-hemoglobin by use of agar diffusion and immunoelectrophoresis, the demonstration of the dependence of complete serologic reactivity on the presence of hematin, and the quantitative recovery of hematin in the immune precipitate. The anti- A 1 sera distinguish the mutant hemoglobins S and C from A 1 by micro-complement fixation but not by quantitative precipitation. The antigenic difference in the abnormal hemoglobins is probably a result of a change in conformation at the N -terminus of the β chain. The quantitative reaction of human A 2 and H was also studied. A 2 hemoglobin was less effective serologically than S or C . Hemoglobin H reacted with anti- A 1 as measured by inhibition of A 1 -anti- A 1 . Variable amounts of antibodies directed toward the β chain were found in the three antisera.

Problems in Differentiating SLE and Mixed Connective-Tissue Disease

Although the nature of systemic lupus erythematosus still poses many mysteries, substantial progress has been made in defining specific autoantigens reactive with the serum of patients with this di...

Immunochemical studies on inter-species molecular hybrids of hemoglobin☆

Abstract Several inter-species hybrids of hemoglobin have been produced, primarily under conditions of acid dissociation but also at alkaline pH. These hybrids have been analyzed using antisera, directed specifically toward horse, human A1, pig, chicken, and mouse hemoglobins. Unfractioned solutions of hybridized hemoglobins fix complement less effectively than the same two hemoglobins incubated separately under identical hybridizing conditions. The isolated hybrids do not fix complement with either homologous antibody at the dilutions of the serum used in the assay, but do not inhibit the homologous systems at these serum dilutions. The hybrids will, however, fix complement if serum concentrations greater than those used to measure the homologous system are used. A variety of hemoglobins from different species has been hybridized and the hybrids detected immunochemically. A mouse-human hybrid system has been analyzed in detail and the serological activities of the isolated hybrids studied quantitatively. Location of the antigenic determinants in two molecules as a result of hybrid formation decreases their serological effectiveness, probably by decreasing the antigenic determinant density. Evidence is presented which demonstrates the feasibility of the immunochemical method being utilized as a measure of hemoglobin hybridization. The possible usefulness of specific antibody in the detection and analysis of hybrid molecules that have been synthetized in vitro is discussed.