Formation of rosettes by nonspecific lymphoid cells which have adhered to antigen-antibody complexes

Rat lymph node-sheep red cell rosettes have been formed through the adherence of nonspecific small lymphocytes and larger cell types to antibody-sheep red cell complexes. Enough antibody to form a significant number of rosettes has been synthesized in cultures, containing draining lymph node cells of immunized rats, within 1 hr of incubation at 37 °C, or during overnight storage at 4 °C. This suggests that conditions which differentiate between specific and nonspecific rosette-forming cells are essential when immunocyto-adherence phenomena are utilized for the study of the specificity of the immune response.     

Post-radiation disorders in the cyclic AMP system of mouse spleen and thymus lymphoid cells]

Early alterations in the enzyme activities controlling cyclic adenosine-3',5'-monophosphate (cAMP) metabolism after the irradiation (800 rad) of mice were found in the lymphoid cells of the spleen and thymus. Postradiation disturbances in these activities' ration induced alterations in cAMP steady-state concentrations in the cell. It was also demonstrated that irradiation reduced lymphoid cell ability to accumulate cAMP in response to isoproterenol administration.     

Changes in rabbit thymus lymphoid tissue after administration of pyrogenal and hydrocortisone]

After a single administration of pyrogenal (0.2 and 5 mkg/kg) and hydrocortisone (100 mg/kg) histological changes in the rabbit thymus have been studied and compared with the level of 11-oxycorticosteroids (11-OCS) in blood of the animals under investigation. Hydrocortisone, while producing a considerable rise in the level of 11-OCS, increases the number of degenerating cells, inhibits mitotic activity and decreases the amount of lymphocytes per stipulated area unit in the cortical substance. Changes produced in the thymus after pyrogenal administration are similar to those produced by hydrocortisone administration but are pronounce much weaker, that is connected with concentration of corticosteroids circulating in blood.     

Migration of thymus cells to the developing gut-associated lymphoid tissues of the young rabbit

Thymus cell migration to the gut-associated lymphoid tissues (GALT) as compared to other lymphoid tissues in young rabbits was determined following in vivo intrathymic inoculation of tritiated thymidine. The GALT received as many or more thymus cells than the spleen or lymph nodes during the first few postnatal days. Migration to the GALT and nonGALT decreased with age, and seeding appeared to be essentially complete by 30–40 days.     

Role of lymphoid cells of the immune system in the genesis of kidney diseases]

Experiments on mice CBA X C57BL showed that the mixture of cells of the bone marrow, thymus, and spleen from donors with experimental hepatitis caused by carbon tetrachloride and from donors with resection of the normal liver, injected to healthy animals, caused dystrophic changes in the liver; this testifies to the presence of a special clone of cells with a damaging hepatotrophic effect, and participating in the mechanism of autoimmune disturbances in diseases of the liver.     

Electrophoretic mobility of human lymphocytes purified by nylon columns and spontaneous rosettes]

Cell electrophoresis enables the separation of the lymphocytes in normal human blood into two principal groups, as a function of their migration speed in relation to 1 mum.sec -1..v-1.cm. In 42 healthy adults, 19,9 % of the lymphocytes have a slower migration, and 80,1 % a faster migration than the reference speed. Two known methods are used for the selection of the lymphocytic populations : spontaneous rosetting with sheep red blood cells, a property of the T lymphocytes, and the adherence to nylon wool columns, which is dominant in the case of B lymphocytes. The cells which do not form spontaneous rosettes, and the cells adhering to nylon wool columns have above all a slow migration. On the contrary, cells which do not adhere to nylon columns have a fast migration. These arguments are in favour of the T nature of the rapid migrating lymphocytes, and of the B nature of the slow migrating lymphocytes.     

Perturbation of early development of the immune system by normal adult lymphoid cells

Seven-day-old C57BL/10 mice injected with 3 X 10(6) normal adult lymph node cells (NAL) from syngeneic donors were compared with uninjected littermates when 5 to 7 wk old. The direct PFC response to sheep erythrocytes was suppressed by 60%. Responses to PHA and Con A but not LPS were suppressed by 60 to 90%. Primary and secondary (after skin graft rejection) MLR responses were suppressed by 30 to 40%. Active suppressor cells were demonstrable in these mice. Skin grafts incompatible for H-2 were rejected in normal time. NAL derived from adult mice conferred the effect, but not cells from 7-day-old donors. Mice inoculated with Rous sarcoma virus within the 1st day of life and 3 X 10(6) NAL at 7 days of age displayed up to 5-fold increased incidence of primary sarcomas.     

B cells in the appendix and other lymphoid organs of the rabbit: Stimulation of DNA synthesis by anti-immunoglobulin

Lymphocytes from rabbit lymphoid organs were cultured in the presence of class specific anti-immunoglobulin sera and of anti-allotype sera. Stimulation of tritiated thymidine uptake into DNA was taken to indicate the presence of the corresponding immunoglobulins on the cell surfaces. Thymus and bone marrow lymphocytes were unresponsive to all reagents tested. Popliteal lymph node contained cells responsive to anti-μ, anti-γ, and anti-α and therefore presumably bearing IgM, IgG, and IgA. Spleen had only IgM- and IgG-bearing-cells, and the appendix contained cells with IgM and IgA receptors only. The lymph node, spleen, and appendix cells of rabbits depleted of B lymphocytes by irradiation (900 R) and injection of thymocytes were unresponsive to anti-immunoglobulin but were stimulated at almost normal levels by PHA and Con A. T cell-depleted animals (thymectomy, irradiation with three divided doses of 450 R and bone marrow shielding) had immunoglobulin-bearing lymphocytes but were unresponsive to the mitogens. However a moderate level of mitogen-responsiveness reappeared by 3–4 wk after irradiation. Cells of morphologically distinct regions of the appendix, separated manually, showed different responses corresponding to the inferred origins of these anatomic areas. The “dome” and “corona” contained functional IgM- and IgA-bearing cells. The “TDA” reacted well to PHA, Con A, and PWM, but was depleted of immunoglobulin-bearing cells. The “follicle” cells, which are almost all in active DNA synthesis or mitosis, were relatively unresponsive to either T or B cell stimuli. Anti-allotype serum stimulated the same populations which responded to class-specific heteroantisera but at a slightly lower level. It was inferred that gut-associated lymphoid tissues like the appendix may play a special role as an amplification site for B-cells destined to produce IgM and IgA elsewhere in the organism.     

Analysis of the mitotic activity of the lymphoid cells of the thymus in relation to age]

The mitotic activity of lymphoid cells of the thymus was studied separately in the subcapsule zone of the cortical substance, cortical substance and medullary substance of newborn, 21-day, 3-, 4-month and 12-month-old mice. In addition to counting mitoses (MA%) histograms of the organ lobes were drawn with exact localization of mitoses of dividing cells. The greatest index of mitotically dividing cells was noted in the subcapsule zone of newborns and 21-day-old mice (5,2+/-0,9 and 4,7+/-0,5). After sex maturation the mitotic activity considerably decreased but in 3-, 4- and 12-month-old mice, the mitotic coefficient of lymphoid cells also retained rather high level (2,6+/-0,3 and 2,1+/-0,2) though processes of involution took place in their thymus.     

Interaction of intact and irradiated macrophages with thymus lymphoid cells

The rat broncho-alveolar macrophages, subjected to gamma-irradiation, were incubated for 4 hours with irradiated (4 Gy) thymocytes. Following the total 24 hour incubation, some morphological features of macrophages were revealed in addition to their influence on survival, autologous rosetting and mitotic index of intact thymocytes. The increase in macrophage spreading was shown which was dose-dependent in the 1 to 4 Gy scale. Enhanced viability of thymocytes was revealed in the presence of macrophages irradiated at the dose of 1-2 Gy. Addition of 24 hour cultures of intact or irradiated macrophages elicited a significant decrease in rosette-forming capacity among thymocytes. Gamma-irradiation of 2 to 4 Gy inhibited the ability of macrophages to suppress the mitotic activity of thymic cells. A possibility of postradiational modification of some specific functions and properties of macrophages, including their thymotropic effects, is discussed.     

A membrane antigen of rabbit thymus cells

Rabbit cells, bearing a thymus-specific antigen, which we call rabbit thymus lymphocyte antigen (RTLA), could be detected with a suitably absorbed heterologous antiserum (goat). In the presence of complement, the RTLA antiserum lysed more than 95% of thymus cells, 70 ± 6% of lymph node cells, 46 ± 10% of spleen cells and 12 ± 7% of bone marrow cells. The number of direct or indirect hemolytic spleen plaques was not reduced by treatment with RTLA antiserum and complement, but was greatly diminished by an unabsorbed thymus antiserum which killed more than 90% of bone marrow cells. RTLA-bearing subpopulations of spleen cells were characterized by velocity sedimentation analysis and were distinguished from Ig receptor bearing subpopulations. The antiserum concentration could be so adjusted that the cytotoxicity against bone marrow was not manifested, while the cytotoxicity against other cell populations remained unchanged. The latter were identified by thymidine incorporation induced by treatment with antibody directed against rabbit light chain allotype. A small subpopulation of thymus cells did not have RTLA antigen and sedimented with a velocity distinct from that of the peak of RTLA-bearing cells.     

Isolation and partial chemical characterization of THF, a thymus hormone involved in immune maturation of lymphoid cells.

A procedure for isolation and characterization of the active principle of calf thymus is described. It consists of homogenization, ultracentrifugation and dialysis of the material. The active dialyzate is further purified by gel filtration on Sephadex G-10 and G-25 columns followed by anion exchange chromatography. The level of purification is assessed by isoelectric focusing on polyacrylamide gels. The active principle is a polypeptide of MW 3220. Determination of the amino acid composition revealed the presence of high proportion of acidic residues.     

Localization of PNA-binding and nonbinding thymus cells in peripheral lymphoid organs

Thymus cells were labeled in vitro with FITC and injected into syngeneic recipients. In cell suspensions of lymphoid organs green cells were inspected for PNA receptors with double immunofluorescence. A striking preference of PNA-negative cells to localize in lymph nodes and the lymphoid compartment of the spleen was demonstrated. Incubation with anti-Ly sera revealed that Ly 1⁺ PNA-negative cells homed in popliteal lymph nodes and Peyer's patch but not in mesenteric lymph nodes.     

The anatomy and topography of the lymphoid formations of the human stomach in postnatal ontogeny]

By means of macro-microscopical methods 80 stomachs from persons of various age have been studied. In the mucous membrane of the human stomach during all age periods of postnatal development the lymphoid tissue is present as diffusely scattered lymphocytes, their microaccumulations and lymphoid noduli. Maximal amount of the lymphoid noduli is observed during the second mature age. The greatest number of the lymphoid noduli per 1 cm2 of the mucous membrane surface is revealed in the area of the lesser curvature and in the pyloric part of the stomach. Most often the lymphoid noduli are situated in the depth of the lumen proper of the mucous membrane, somewhat more seldom--in its more superficial parts, in the muscular lamina and in the submucous tela. The lymphoid noduli with germinative centers are met beginning from the first childhood up to old age. The greatest amount of diffusively scattered lymphocytes is situated near the lymphoid noduli and in the deep layer of the lamina proper of the mucous membrane.