Properties and kinetics of a population of B-lymphocytes during rat ontogenesis]

Cells bearing surface immunoglobulins (Ig+-cells) detected by the indirect immunofluorescent method and cells forming rosettes (RFC) with sheep erythrocytes coated with antibody and complement (EAC rosettes) were found in the liver and the spleen on the 15th and the 20th days of prenatal life of rats. The percentage of Ig+-cells and RFC in the liver was high and remained unchanged and at about the same level during the whole postnatal life. The spleen and the bone marrow displayed an increase of the Ig+-cells and RFC increased throughout the 1st month of postnatal life with the maximum at the 30th day after birth; a sharp decrease occurred in old animals. In the thymus the Ig+-cells and the RFC were either absent or present in very small amounts only at some periods of study. Ig+-cells with "capping" were discovered in the spleen and bone marrow on the 5th--10th days of postnatal life; their count increased considerably in 30-day and adult rats. Such cells were absent in the lymphoid tissues of old 40-month rats.     

Types of cells involved in antigen-stimulated and spontaneous rosette formation with Toxoplasma gondii.

Antigen-binding cells were identified by using rosette formation of Toxoplasma gondii and defined lymphoid populations under different experimental conditions. Treatment of immunized spleen cell suspensions with anti-Thy 1 serum plus complement inhibited 5 to 29% of the rosette-forming cells (RFC). Higher numbers of thymus-derived lymphocyte-RFC were obtained after incubation at 4 degrees C and by the centrifugation method than by simple incubation at 20 degrees C. RFC were also observed with thymocytes. Combined treatment with anti-Thy 1 serum plus complement and depletion of adherent cells indicated that the major proportion, 46 to 70%, of RFC were B cells. Spleenocytes of nu/nu mice formed similarly high numbers of rosettes. Spontaneous RFC were observed in nonimmunized mice with both spleen and thymus populations. Numbers of rosettes varied considerably depending on the method and the source of cell population used. Removal of adherent cells from spleen suspensions resulted in RFC reduction of 14 to 25% in immunized and 14 to 33% in nonimmunized animals. Pretreatment with anti-mouse immunoglobulin inhibited completely the spleen and spontaneous thymus RFC and partially the thymus RFC in immunized animals.     

Lymphocyte subpopulations in sensitization and specific immunotherapy in an experiment. Lymphocyte subpopulations in sensitization to staphylococci, Artemisia pollen and their combinations

The distribution of T- and B-lymphocytes in the body of guinea pigs was studied in different groups of the animals. As shown in this study, in delayed hypersensitivity to staphylococci the number of PE- and E-rosette-forming cells increased in the blood, the spleen, and the lymph nodes and decreased in the thymus; the number of EA- and EAC-rosette-forming cells decreased in the bone marrow and the spleen, the number of T gamma-suppressors decreased in the bone marrow and the distant lymph node. Immediate hypersensitivity to tarragon pollen induced the general increase of the content of T- and B-lymphocytes; the number of T gamma-cells decreased in the thymus, the bone marrow, and the lymph nodes and increased in the spleen. The characteristic features of combined microbial-pollen sensitization were the high content of B-cells in all lymphoid organs (except the thymus), a low level of T-lymphocytes in the blood and the peripheral lymphoid organs, the decreased number of T gamma-cells in most of the immunogenetic organs.     

The morphological characteristics of globulin production during the vaccinal process induced by tularemia and brucellosis vaccines

Significant data on the dynamics of globulin production in guinea pigs in the process of immunogenesis after the injection of Francisella tularensis vaccine strain or conjugated brucellosis vaccine have been obtained by means of immunofluorescence and the enzyme immunoassay. The number of globulin-producing cells in lymphoid organs (the spleen, regional and remote lymph nodes) differs, depending on the injected antigen. The relationship between the character of immunomorphological changes in lymphoid organs and the dynamics of the increase of antibody titers in the peripheral blood of the animals after their immunization with conjugated brucellosis vaccine and the injection of avirulent F. tularensis has been established.     

The development of the lymphoid organs of flounder, Paralichthys olivaceus, from hatching to 13 months

The growth of the lymphoid organs, such as head kidney, spleen and thymus were studied in flounder, Paralichthys olivaceus Temminck & Schlegel, from hatching to 13 months of age. Except for the thymus, all organs grew as the fish grew. By 2 months of age the lymphoid organs attained their maximum relative weight. The organ weight showed a closer correlation to body weight than they did to age. The total number of leucocytes in the lymphoid organs increased with age, but the number per milligram of lymphoid organ remained constant. A micro and ultrastructural study of the lymphoid organs showed that the full development of the lymphoid organs was not achieved until the juvenile stage. The spleen and head kidney had mixed populations of "red" and "white" cells. The head kidney was more lymphoid than the spleen. The thymus involuted quickly during the first 6 months. The blood components had no obvious relationship with age or season during the period studied.     

Nuclear RelB+ cells are found in normal lymphoid organs and in peripheral tissue in the context of inflammation, but not under normal resting conditions

Differentiated dendritic cells (DC) have been identified by the presence of nuclear RelB (nRelB) and HLA-DR, and the absence of CD20 or high levels of CD68, in lymph nodes and active rheumatoid arthritis synovial tissue. The current studies aimed to identify conditions in which nRelB is expressed in human tissues, by single and double immunohistochemistry of formalin-fixed peripheral and lymphoid tissue. Normal peripheral tissue did not contain nRelB+ cells. nRelB+ DC were located only in T- or B-cell areas of lymphoid tissue associated with normal organs or peripheral tissues, including tonsil, colon, spleen and thymus, or in association with T cells in inflamed peripheral tissue. Inflamed sites included skin delayed-type hypersensitivity reaction, and a wide range of tissues affected by autoimmune disease. Nuclear RelB+-HLA-DR- follicular DC were located in B-cell follicles in lymphoid organs and in lymphoid-like follicles of some tissues affected by autoimmune disease. Lymphoid tissue T-cell areas also contained nRelB(-)-HLA-DR+ cells,some of which expressed CD123 and/or CD68. Nuclear RelB+ cells are found in normal lymphoid organs and in peripheral tissue in the context of inflammation, but not under normal resting conditions.     

Rescue of embryonic lethality in reduced folate carrier-deficient mice by maternal folic acid supplementation reveals early neonatal failure of hematopoietic organs

The reduced folate carrier (RFC1) is an important route by which the major blood folate, 5-methyltetrahydrofolate, is transported into mammalian cells. In this study we determined the consequences of inactivation of RFC1 in mice by homologous recombination. While RFC1-null embryos died in utero before embryonic day 9.5 (E9.5), near-normal development could be sustained in RFC1(-)/- embryos examined at E18.5 by supplementation of pregnant RFC1(+/-) dams with 1-mg daily subcutaneous doses of folic acid. About 10% of these animals went on to live birth but died within 12 days. These RFC1(-)/- mice showed a marked absence of erythropoiesis in bone marrow, spleen, and liver along with lymphoid depletion in the splenic white pulp and thymus. In addition, there was some impairment of renal and seminiferous tubule development. These data indicate that in the absence of RFC1 function, neonatal animals die due to failure of hematopoietic organs.     

Intracellular localization of anti-tumor immune RNA.

Syngeneic spleen cells from normal, non-immune Fischer 344/N rats and allogeneic spleen cells from normal Wistar-Furth rats became cytotoxic, in vitro, to chemically induced Fischer rat sarcoma (MC3-R) target cells following incubation with xenogeneic Immune RNA (I-RNA) extracted from spleens of guinea pigs immunized with MC3-R tumor cells. I-RNA extracted from intact spleen cells or from the cytoplasmic fraction of spleen cells were equally active. RNA extracted from isolated spleen cell nuclei was inactive, as were all RNA fractions from spleen cells of nonspecifically immunized guinea pigs. Syngeneic I-RNA extracted from intact spleen cells or the cytoplasmic fraction of cells from spleens of Fischer rats bearing growing MC3-R transplants mediated cytotoxic reactions against MC3-R target cells when incubated with normal Fischer rat spleen cells. RNA from the nuclei of spleen cells of rats bearing MC3-R tumors was considerably less active. All RNA fractions from spleen cells of normal non-immune Fischer rats were inactive. The immunologically active component of xenogeneic and Syngeneic I-RNA, therefore, were found to be localized in the cytoplasm of specifically sensitized lymphoid cells.     

Quantitative evaluation of the total number and distribution of lymphocytes in young pigs.

In young pigs, the spleen, thymus and all lymph nodes were dissected out and weighed. The relative content of lymphoid cells was determined from histological sections. The number of nucleated cells was evaluated by two different methods: firstly, by measuring the DNA content of samples of lymphoid tissue and dividing by the DNA content of a single nucleus; and, secondly, by counting all lymphoid cells in histological sections of defined volumes of these organs. The number of lymphoid cells in tonsils, gut, bone marrow and lung were determined using histological evaluations and the volumes or weights of these organs. The resulting average number of lymphocytes was 321 times 10 (9) for a pig of 26 kg body weight. The lymphocytes showed the following distribution in lymphoid and non-lymphoid organs: thymus 44%, spleen 9%, mesenteric lymph nodes 17%, cervical lymph nodes 9%, other peripheral lymph nodes 3%, gut-associated lymphocytes 5%, tonsils 2%, bone marrow 5%, blood 3%, lung 0.2% and an estimated figure of 3% for all other tissues.     

IgM complex receptors on subpopulations of murine lymphocytes.

Murine lymphocytes from spleen, lymph node, and thymus were examined for IgM complex receptors. Lymphocytes from all three organs were found to bind SRBC sensitized with IgM from various sources including: primary anti-SRBC serum, murine and rabbit anti-Escherichia coli LPS sera, and a murine IgM myeloma (MOPC 104E). Rosette formation by lymphocytes with IgM-sensitized SRBC was inhibited by soluble antigen-IgM complexes but not by IgM or antigen alone. Rosette formation was also inhibited by human IgM (Fc)5mu but not by Fab mu. Antiserum and complement treatment of the cells and subsequent recovery of the viable cells by trypsinization, filtration, and washing revealed the IgM rosette-forming cell (RFC) in the thymus to be a T cell. Spleen on the other hand was found to contain both B and T cells capable of binding IgM sensitized SRBC. Removal of both B and T cells from spleen cell suspensions eliminated all IgM RFC. The IgM complex receptor was found to be trypsin insensitive. Anti-Ig column fractionation enriched IgM RFC in spleen and lymph node suspensions passed through the columns, whereas cells bearing surface Ig, IgG complex receptors, and C3 receptors were retained in the columns.     

Immune reconstitution in the immunodeficient chicken by transfer of embryonic lymphoid cells

Embryonic chickens were rendered immunodeficient by in ovo injection of homologous IgM on the 10th embryonic day. The immunodeficient embryos were intravenously given lymphoid cells taken from normal embryonic bursa, spleen or thymus on the 15th embryonic day. Gain of splenic or bursal weight, natural antibodies to sheep red blood cells (SRBC), frequencies of rosette forming cells (RFC) binding to SRBC or dinitrophenyl-SRBC (DNP-SRBC) and of immunoglobulin bearing cells (IBC) in the bursa and the spleen were investigated to assess the effect of transferred cells during the embryonic stage. Transferred bursal and splenic cells showed an ability to restore the frequency of RFC or IBC in the recipients. However, reversion from the immunodeficient state was not observed in the thymic cell transfer. These findings suggested that the cells derived from embryonic bursa and spleen contained stem cells which developed into RFC and also into precursors of IBC.     

Dynamics of immunoglobulins and immunocompetent lymphocytes in guinea pigs with experimental ascariasis

The paper presents data on variations in the level of serous immunoglobulins (Ig M and Ig G classes), immunocompetent T- and B-lymphocytes in lymphoid organs (spleen, mesenteric, portal and mediastinal lymph nodes) and specific antiparasitic antibodies in guinea pigs during the dynamics of experimental ascariasis.     

Combined reaction of the lymphoid organs and the adrenals to stress in mature animals subjected to cold in the early period of postnatal ontogeny

Structural-functional organization of the lymphoid organs and functional state of the adrenals have been studied in animals, subjected to cold in early postnatal period, as well as changes of the parameters mentioned to a short and prolonged cooling in mature rats. For the animals increase in the thymus mass and in reproduction rate of lymphocytes in the thymus, spleen and lymph nodes is specific against the background of high corticosteroid secretion. When the control animals are kept in cold for a long time, after the phase of an acute stress, accompanied with hypercorticism and a pronounced lymphatic effect, during the period of an increased cold stability, the high secretion of glucocorticoid hormones is accompanied with a certain activation of thymus-dependent zones in the peripheral lymphoid organs. In the mature rats, subjected to cold at early ontogenesis both stress-reaction to cooling and rearrangement in the regulatory systems studied does not develop at adaptation to cold.     

Studies on the resistance to tolerance induction against human IgG in DDD mice. I. Organ differences of tolerogen susceptibility and cellular sites responsible for the resistance.

Cellular sites of the tolerogen resistance in DDD mice against human IgG (HGG) were examined by reconstitution experiments in which cells of various lymphoid organs from tolerized mice were transferred into lethally irradiated syngeneic recipients with or without the supplement of an excess number of untreated T or B cells. It was shown that T cells but not B cells in the spleen and bone marrow-locating B cells were tolerogen resistant. Kinetic profiles of tolerance induction were compared among thymus, lymph node, and spleen T cells. Thymus cells fall into unresponsive state as early as 2 days after the tolerogen (tHGG) injection when only partial tolerance was observed in lymph node T cells. By 1 week of tolerogen treatment, the tolerant state was completed in both thymus cells and lymph node T cells, while spleen T cells showed marked resistance. Tolerance induced in thymus cells and spleen T cells was of relatively short duration and responsiveness was completely recovered by 5 weeks after the injection of tHGG. At this time lymph node T cells still showed hyporesponsiveness. The differences in tolerance inducibility were also shown among different lymphoid organs in tolerogen dose response. Lymph node T cells were very sensitive to tolerance induction, giving no response even by the injection of 0.01 mg of tHGG. Thymus cells were much less sensitive with the gradual loss of responsiveness by increasing the amount of tHGG. In contrast, spleen T cells showed gradual resistance with increasing amount of tHGG, indicating that some positive response was evoked in spleen T cells by a relatively high dose of tHGG. These results seem to suggest that the tolerogen resistance of spleen T cells may be due to their capability of showing positive response against the tolerogenic material. This was also suggested by the fact that the treatment with cyclophosphamide following the tolerogen injection diminished completely the responsiveness against the subsequent challenge immunization.     

Lymphoid organ weights and organ:body weight ratios of growing beagles

Although dogs, especially beagles, are used extensively in biological and clinical investigations, the literature dealing with normal biological measurements of their lymphoid organs is scanty. This study was undertaken to provide the information on the weight of lymphoid organs of beagles. The thymus, spleen, and prescapular, popliteal, and mesenteric lymph nodes of 95 normal beagle dogs, from one day to 11 months of age, were weighed and compared with body weights. The weight of the thymus and spleen increased drastically at and after 2 months of age, although the organ:body weight ratios remained the same at 2 months of age and decreased afterward. Similar increases in the weight of the mesenteric lymph node complex, but with an increase in the organ:body weight ratio, occurred also at and after 2 months of age, reflecting the importance of the gut-associated lymphoid organs after weaning. The increases in the size of the cutaneous nodes, prescapular and popliteal, were less pronounced and their organ:body weight ratios remained the same from birth through 11 months of age.     

Microscopic observations of skin and lymphoid organs in the hairless dog derived from the Mexican hairless

The skin and lymphoid organs of Mexican hairless dogs and their hairless offspring were examined histologically. The hairless dogs lacked most hairs except for sparse hairs on the head, tail and feet. The skin of newborn pups consisted of a thick epidermis with epidermal ingrowths forming the rudiments of hair follicles. In older dogs more than 2 months of age, however, the epidermis was thin and the ingrowths were few. Neither hair follicles nor skin glands were present. The hairy skin of the head and tail had hair follicles with sebaceous glands. Regarding the lymphoid organs, the newborn pups possessed a thymus like haired pups. But in the older dogs more than 2 months of age, the thymus was atrophied and the lymphocyte population was too sparse to demarcate the cortex and the medulla. Lymphocyte accumulation in older dogs was also poor in the spleen and mesenteric lymph nodes. The present findings indicate that the hairlessness of the Mexican hairless dogs and their descendants is accompanied by early atrophy of the thymus after birth, and is followed by poor accumulation of lymphocytes in the thymus-dependent area of the spleen and the mesenteric lymph nodes. The defect of the thymus in the hairless dog seems to be different from that in athymic nude mice and rats. Further studies are needed to elucidate the immunological response and function in hairless dogs.     

Morphometric ultrastructural evaluation of human peripheral blood T lymphocyte subpopulations isolated on the basis of their affinity for sheep red blood cells

The present investigation were undertaken to compare on the basis of ultrastructural morphometric analysis human T lymphocyte subfractions forming rosettes with sheep red blood cells (SRBC). The following T lymphocyte subfractions were obtained: ARFC (active rosettes), T1RFC (rosettes after 1 h at 4 degrees C) and T2RFC (rosettes after 2 h at 4 degrees C). Analysis of the mean cell and nuclei volumes of lymphocyte subfractions led to the separation of two cell groups differing in volume in each donor: a cell group consisting of large cells (T1RFC) and group of small cells (ARFC and T2RFC).     

Ontogeny of IgM-producing cells in the lymphoid organs of rainbow trout, Salmo gairdneri Richardson: an immuno- and enzyme-histochemical study

The ontogenetic development of IgM-containing cells is described as demonstrated by immunoperoxidase staining with a mouse anti-trout IgM monoclonal antibody and the differentiation of enzyme-histochemical markers in the non-lymphoid cells forming the stroma of the thymus, spleen and kidney of the rainbow trout. The first lymphoid cells staining with the monoclonal antibody occurred at day 4-5 after hatching in the renal lympho-haemopoietic tissue. By 1 month after hatching IgM-positive cells also appeared in the spleen and thymus. Enzyme-histochemical demonstration of the alkaline and acid phosphatase and non-specific σ-naphthyl acetate esterase enzymatic activities in the non-lymphoid cells indicated that a certain degree of maturation of the cellular stroma of the developing lymphoid organs of trout was reached before or at the time when IgM-expressing cells could be observed. The relationships of the stromal components of the various lymphoid organs to the development of IgM-positive cells, and the possible role of the renal lympho-haemopoietic tissue as a primary lymphoid organ for B-cell differentiation in the trout are discussed.     

Thymic and splenic changes following injection of living Brucella and BCG in the Guinea pig

Summary The thymic and splenic reactions, following injections of BCG and living Brucella M. in the guinea pigs, were studied. Both microorganisms injected intravenously produced thymic involution, maximal after BCG inoculation, followed by regeneration that was complete by day 10 in Brucella M.-treated guinea pigs, and by day 15, in BCG injected guinea pigs. Increase of mitotic index was more accentuated and more persistent after Brucella M. than after BCG treatment in the thymus. After a short involution period the spleen of injected animals increased in size in both groups. The splenic enlargement was dramatic and occurred at an accelerated rate in animals given BCG. It appeared to be the result of a conspicuous involvement of the red pulp by multiple granulomas. In Brucella M. treated guinea pigs the splenic enlargement was less obvious, but the splenic white pulp was more abundant in BCG-treated guinea pigs. Granulomas were observed only in the periarterial sheaths of the white pulp.These observations provide evidence for the hypothesis that injections of both BCG and Brucella M. provoke a proliferation of B and T lymphocytes, a migration of T lymphocytes from the thymus to the T-dependent area of the spleen which seems, perhaps, more marked after injection of Brucella M., and a strong granulomatous histiocytic reaction which is more conspicuous in animals given BCG.     

Time dependent effects of hormones on rate of protein synthesis in lymphoid organs of chickens

Total protein content in blood serum and different lymphoid organs, such as bursa, spleen and thymus was investigated in chickens at two different circadian stages (0800 or 1600 hrs; early or late photophase) following administration of either saline or hormones (thyroxine or hydrocortisone or epinephrine). The results suggest that the lymphoid organs may respond differently to the exogenous administration of different hormones depending on the time of their administration.