Role of the Thymus in Immune Reactions in Rats

Abstract

Rats thymectomized at birth gained weight and otherwise developed normally, but were found to be very susceptible to intercurrent infections. Both Arthus reactivity and delayed hypersensitivity to BSA were markedly impaired in rats thymectomized during the first week of life and significantly impaired in rats thymectomized as late as 3 weeks after birth. The inhibition of Arthus reactivity in thymectomized rats was well correlated with their failure to develop significant titers of precipitating or hemagglutinating antibody. However, natural heteroagglutinin titers were not altered in these animals, and no abnormality of serum proteins, including γ-globulin could be detected by paper electrophoresis. The loss of immunologic activity could not be corrected by injecting homogenates of spleen or thymus before and during the sensitization period. Splenectomy at birth did not influence Arthus or delayed reactivity.

Anatomical Distribution of T and B Lymphocytes in the Rat

“…1, 8, and 10, respectively; center well, normal rat serum. There is complete fusion of the lines formed by ALSo, 1,8, and 10; and partial fusion of the lines formed by ALSB 1 and anti-Ig serum, and by ALSB 8 and anti-Ig serum.…”

“…The cells were removed by centrifugation and the sera resterilized by passage through a Millipore membrane. Multiple absorptions (2)(3)(4)(5)(6)(7)(8) were often necessary to completely remove reactivity for any cell type, as judged by indirect immunofluorescence. Absorptions of a single serum with cells from more than one source were done sequentially.…”

Studies on the role of the thymus in immunobiology. Reconstitution of immunologic capacity in mice thymectomized at birth

“…Some of the characteristics of the mice thymectomized at birth have also been described in other species subjected to neonatal thymectomy: the rat (15)(16)(17), rabbit (3,10,18), and hamster (19)(20)(21)(22). Particularly interesting are the findings in the thymectomized hamster in which a wasting syndrome associated with hypogammaglobulinemia has been observed (19).…”

The early history of B cells

“…However, after learning that early removal of the avian bursa of Fabricius impaired the development of antibody responsiveness, they found that thymectomy of newborn mice and rabbits inhibited lymphocyte development and both cellular and humoral immune responses 22 . Branislav Jankovic and co-workers 23 found that thymectomy of neonatal rats had similar immunological consequences.…”