Ronald L. St. Pierre

The effect of chronic alcohol administration on the immune responsiveness of rats

Abstract A series of studies were carried out to determine the effect of chronic alcohol administration on cellular and humoral immunity in the rat. Alcohol-treated rats received an alcohol liquid formula diet for 3 months, and this uniformly resulted in the development of a fatty liver. In alcohol-treated rats there was a delay in antibody production to both typhoid H and B. abortus antigens following a primary immunization. The peak titers obtained, however, were not significantly different from those of the control animals. The secondary response to typhoid H antigen was not affected. The expression of cutaneous delayed hypersensitivity to a potent skin sensitizing chemical, 2, 4-dinitrofluorobenzene, was also depressed in alcohol-treated rats. Animals receiving alcohol also had markedly atrophic thymuses and small spleens. The normal thymuses and adrenal glands found in control animals treated with ACTH injections indicate that the changes were not due to hyperactivity of the adrenal cortex in a stressful situation. It is postulated that the deleterious effects of alcohol on the immune system of rats may be due to alteration in either reticuloendothelial or thymic function.

Bursa of Fabricius in Chickens: Possible Humoral Factor

Chicks bursectomized by testosterone injection on the 5th day of incubation showed a marked inability to produce antibodies to Salmonella typhimurium. When portions of the bursa of Fabricius were enclosed in cell-impermeable Millipore diffusion chambers and implanted subcutaneously or intraperitoneally, the antibody-producing capacity of these animals was restored. Evidence strongly suggests that the bursa of Fabricius elaborates a non-cellular agent capable of restoring immunologic reactivity in bursectomized chicks.

INDUCTION OF T-CELL DIFFERENTIATION IN VITRO BY THYMUS EPITHELIAL CELLS*

Thymus-reticular epithelial cells (TE-cells) were grown in a cell culture devoid of any lymphocytic elements. These cells were able to induce T-cell differentiation in spleen cells from T-dificient mice as expressed by con-A responsiveness and GvH reactivity. It was also shown that xenogeneic rat TE cells were as effective in the induction of T-cell differentiation in vitro as syngeneic TE cells. This system is therefore ideal for the study of T-cell development.

Analysis of cellular heterogeneity in mouse thymus cultures

SummaryAnalysis of 5 to 6 d primary cultures of cells derived from murine thymus glands revealed a heterogeneous population of cells rather than “pure” reticuloepithelial cell cultures as was assumed previously by other investigators. The monolayer cultures consisted of at least three cell types: thymus epithelial cells, macrophagelike epithelioid cells, and fibroblasts. Surprisingly, about 50% of the cells had positive cytochemical staining reactions for acid phosphatase and nonspecific esterase. The same cells phagocytized carbon particles, latex beads, and yeast. Furthermore, these cells could be removed from the initial cell suspension by phagocytosis of carbonyl iron, followed by magnetic separation, but once they had adhered to the substratum they were resistant to trypsin removal. All of these findings supported the conclusion that about 50% of the cells in the monolayers were macrophages. The other cells present were thymus epithelial cells and a small number of fibroblasts. Both of the latter types of cell were cytochemically negative, did not phagocytize particulate material, and were not removed by carbonyl iron treatment, but were removed by treating the monolayer with trypsin. The findings in this report indicated that epithelioid morphology alone was inadequate to identify correctly the cell types found in thymus cultures and that the use of such cultures as a model to study in vitro the maturation of certain immunological functions has been based on assumptions here shown to be incorrect.

Hemopoietic tissue in the adult newt, Notopthalmus viridescens†‡

The presence of developmental stages of lymphocytes and their precurors, as revealed by serial and thin sections of hemopoietic organs of normal adult newts (Notopthalmus viridescens) suggests that lymphopoiesis is limited to the thymus, medulla of the spleen and, to a lesser degree, the intestine. Stromal cells, small lymphocytes, granulocytes, mature erythrocytes and melanocytes were observed either within or near the parenchyma of the thymus. The urodele thymus differs from the thymus of anurans and higher vertebrates in that it lacks a cortex and a medulla, myoid cells and Hassalls corpuscles.

Influence of bursa implantation upon lymphocytic nodules and plasma cells in spleens of bursectomized chickens.

Summary Implantation of donor bursa in hormonally bursectomized chickens restored the immunological reactivity by means of a humoral substance capable of passing through cell-impermeable diffusion chambers. Lym-phocytic nodules, shown to develop under the influence of the humoral agent from the bursa, are felt, in part, to be the site of antibody production. Plasma cell development does not appear to be by means of the humoral substance alone.

Inability of Neonatal Rabbit Thymus to Induce Antibody Producing Capacity in Bursectomized Chickens.

Summary Implantation of neonatal rabbit thymus in either surgically or hormonally bur-sectomized chickens has failed to restore im-munological competence as measured by their ability to produce antibodies to S. typhi-murium.