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R Benner

Publications and source records attributed to R Benner.

At least 199 records · Page 11Linked to original sources
PubMed1979

Studies on the mechanism of haemopoietic stem cell (CFUs) mobilization. A role of the complement system.

A variety of substances can mobilize haemopoietic stem cells (CFUs) into the peripheral blood. In this study the involvement of the complement system in the mobilization process was investigated. Pretreatment of mice with the complement-activating factor of cobra venom (CoF), which lowered the serum C3 levels to 10-25% of the normal value, could completely prevent CFUs mobilization induced by high doses of CoF, endotoxin (ET) from Salmonella typhosa, inulin, zymosan and the proteolytic enzymes proteinase and trypsin. On the other hand, mobilization induced by the polyanions dextran sulphate and the copolymer of polymethacrylic acid and styrene could not be prevented, or at least affected only slightly. There appears to be a relationship between the extent of decomplementation by CoF and the extent of CFUs mobilization induced by ET. The results indicate that certain agents mobilize CFUs via the complement system, whereas other agents induce CFUs mobilization independent of the availability of complement components.

Animals↗
PubMed1979

Alterations in granulation tissue growth induced in vivo by lymphocytes from adjuvant-diseased rats.

Lymph node cells from Lewis and Wistar rats, treated 9 or 11 days previously with Freund's complete (FCA) or incomplete adjuvant (FIA), were transferred into polyether sponges implanted subcutaneously into syngeneic, recipient rats. FCA-treated lymphocytes enhanced or reduced granuloma formation (measured after 8 days), when compared with FIA-treated controls, depending on the strain of mycobacterium present in the FCA. The stimulatory effects of lymphocytes from FCA-treated, Lewis rats were abolished by pre-incubation with mitomycin C (25 microgram/ml). Whole serum and isolated serum immunoglobulin from adjuvant-diseased rats had no effect on the sponge granulomas. These data confirm that cell-mediated immunity is involved in the articular granuloma formation of adjuvant arthritis.

Animals↗
PubMed1979

Serum immunoglobulin levels in mice. Determination of the low IgA level in AKR mice by an irradiation-resistant factor.

A comparison was made between the serum immunoglobulin (Ig) levels in H-2 compatible AKR and C3H mice. The IgG1 and especially the IgA level in preleukemic AKR mice was much lower than in age-matched C3H mice, while the IgM concentration was hardly different for AKR and C3H. Lethally irradiated AKR and C3H mice reconstituted with syngeneic bone marrow (BM) cells showed a return to serum Ig levels which are normal for these strains. In AKR mice reconstituted with C3H BM cells low IgA levels were observed. On the other hand, in C3H mice reconstituted with AKR BM cells high quantities of IgA appeared, showing the AKR allotype. It is concluded that the low serum IgA concentration in AKR mice is not a reflection of a genetically determined inability of the B cell line to produce IgA, but rather a manifestation of a genetically determined capability to prevent IgA synthesis.

Animals↗
PubMed1979

The distribution of cytoplasmic immunoglobulin containing cells over various lymphoid organs of congenitally athymic (nude) mice as a function of age.

The distribution of cells containing cytoplasmic immunoglobulin (C-Ig cells) over various lymphoid organs was studied in congenitally athymic (nude) mice as a function of age. The C-IgM, C-IgG and C-IgA cells were enumerated in spleen, bone marrow, mesenteric lymph node and Peyer's patches of nude mice and their heterozygous littermates of 6, 40 and 100 weeks of age. In the nude as well as in the heterozygous mice an age-related shift was observed in the localization of the C-Ig cells. In young mice of both groups the majority of these cells resided in the spleen, whereas in adult and old mice the bone marrow was found to be the major C-Ig cell organ, indicating that this shift is not dependent on the presence of the thymus. In young and adult nude and heterozygous mice C-Ig cell numbers in the spleen were comparable, whereas C-Ig cell numbers in the other lymphoid organs were higher in the heterozygous mice than in the nude mice. The total C-Ig cell number in young and adult nude mice was lower than in heterozygous mice of the same age, whereas in old nude mice they were as high as in heterozygous mice of the same age, indicating a retarded development of the immunological activity in nude mice. C-Ig cells in nude mice were almost exclusively of the IgM class, although in the bone marrow of the oldest animals also a substantial number of C-IgG and C-IgA cells was observed. Our finding that nude mice can live up to at least two years of age indicates that the age-related deterioration of the thymus-dependent limb of the immune system is not the cause of ageing, but rather a consequence of it.

Aging↗
PubMed1978

B lymphocyte differentiation in lethally irradiated and reconstituted mice. A histological study using immunofluorescent detection of B lymphocytes.

The recovery of the B lymphocyte compartments was investigated in lethally irradiated mice reconstituted with fetal liver cells. This was done by means of immunofluorescence on frozen sections of spleen, lymph nodes and Peyer's patches. The first B lymphocyte recovery in the spleen was observed on day 8, a few days earlier than in lymph nodes and Peyer's patches (day 13). These early B cells in the spleen were found in the central part of the periarteriolar lymphatic sheath (PALS). Later on, while increasing in number, the B cells formed growing follicles at the periphery of the PALS. Subsequently, brightly fluorescent B cells appeared in the marginal zone, which surrounded the follicles. Another two weeks later, around day 30, also germinal center formation was observed in the follicles of the spleen. B cell development in lymph nodes and Peyer's patches started somewhat later than in the spleen, but once started, the recovery of the different compartments was completed very fast. Germinal center reactions were found in lymph nodes and Peyer's patches already on day 25, and thus earlier than in the spleen, but later than the first occurrence of the strongly fluorescent cells in the marginal zone. Apparently, germinalcenter formation is not essential for the recovery of the population of brightly fluorescent B cells in the marginal zone after irradiation and reconstitution.

Animals↗
PubMed1978

Immunobiology of the graft-versus-host reaction. I. Symptoms of graft-versus-host disease in mice are preceded by delayed-type hypersensitivity to host histocompatibility antigens.

During initiation of an acute graft-versus-host reaction by injection of C57BL/Rij spleen cells into lethally irradiated (C57BL/Rij X CBA/Rij)F1 hybrid mice, a state of delayed-type hypersensitivity (DTH) against host histocompatibility (H) antigens occurs. This was demonstrated by means of transfer of host spleen and lymph node cells into C57BL/Rij recipients, which received a challenge with CBA/Rij spleen cells. Initiation and transfer of the graft-versus-host-related DTH reactivity was highly dependent on Thy-1.2+ cells. The development of DTH reactivity started between 8 and 24 hr after semiallogeneic spleen cell transplantation and increased during the days thereafter. In the spleen maximal DTH reactivity was found on day 4, whereas in the lymph nodes maximal reactivity occurred on day 5 after irradiation and reconstitution. Thereafter, the reactivity decreased until there was no further DTH reactivity demonstrable on day 13. The specificity of the DTH reactivity for host H antigens was proved by no reactivity to a challenge of DBA/2 and Swiss spleen cells, which are H-2-incompatible with CBA cells.

Animals↗
PubMed1978

Regulating influence of transferred immune spleen cells on the primary response of mice to sheep red blood cells.

The regulating influence of transferred immune spleen cells on the primary response of mice to sheep red blood cells (SRBC) was investigated. When splenic memory cells were intravenously inoculated, the greater part of these cells disappeared from the peripheral blood between 30 min and 6 h after injection. Transfer of immune spleen cells 2 days before immunization with 4 X 10(8) SRBC intravenously caused decreased numbers of PFC in the recipient spleen and up to 10 times as many PFC in the bone marrow. Apparently, the regulating influence of immune spleen cells upon antibody formation during the primary response can differ in different organs.

Animals↗
PubMed1977

Mobilization of B and T lymphocytes and haemopoietic stem cells by polymethacrylic acid and dextran sulphate.

The leucocytosis which can be evoked by the polyanions dextran sulphate (DS), polymethacrylic acid (PMAA) and the copolymer of PMAA and styrene (PMAA--STYR) was studied in mice. After intravenous administration of these polyanions peak numbers of leucocytes were found in the peripheral blood 3 hr after injection. All three types of polyanions increased the number of lymphocytes, granulocytes and monocytes. Dose--response studies revealed that the nature of the polyanion determined the degree of leucocyte mobilization. The most potent mobilizer was found to be DS. This polyanion could evoke a six-fold increase of the number of peripheral blood leucocytes. By means of the membrane fluorescence technique it could be demonstrated that optimal doses of DS, PMAA and PMAA--STYR mobilized both B and T lymphocytes. The ratio between the number of B and T cells mobilized was greater for DS than for the other two polyanions. Intravenous injection of DS, PMAA and PMAA--STYR also increased the number of circulating haemopoietic stem cells (CFU-S). The most potent stem cell mobilizer appeared to be PMAA--STYR. This polyanion evoked a twenty-five-fold increase in the number of CFU-S.

Acrylic Resins↗
PubMed1977

B memory cells in the thymus: part of the pool of potentially circulating memory cells.

Immunization of mice with sheep red blood cells (SRBC) or Escherichia coli lipopolysaccharide (LPS) induces the appearance of B memory cells in the thymus. In this paper the origin of these B memory cells was investigated. Therefore, mice primed with either SRBC or LPS 6 months previously and nonprimed mice were joined for parabiosis. Four weeks later the parabiotic mice were separated from each other. Another 3 weeks later thymus cells from the primed and nonprimed mice were transferred separately into lethally irradiated mice in order to determine the adoptive PFC response. It was found that the 4-week period of parabiosis could account for the appearance of a distinct population of B memory cells in the thymus of the nonprimed mice. This result suggest that the B memory cells which appear in the thymus belong to the pool of potentially circulating memory cells.

Animals↗