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Query: UMLS:C0153470 (Spleen)
 4,015 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Spleen cells from male (CBA/N x DBA/2) F1 hybrid mice do not significantly respond to in vitro stimulation by trinitrophenyl-conjugated polyacrylamide beads (TNP-PAA), whereas the same antigen elicits high PFC responses in female F1 hybrid cells. Therefore, this antigen could be classified as a T-independent type 2 (TI-2) antigen. When male spleen cells were co-stimulated by TNP-PAA and TI type 1 antigen, either LPS or Brucella abortus, they produced vigorous anti-TNP responses. A similar increase of the in vitro responsiveness of male F1 hybrid spleen cells to TNP-PAA antigen was provoked by the addition of supernatants from P 388-D1 cells stimulated by muramyl-dipeptide (MDP) mainly containing interleukin-1 (IL-1) or supernatants from phorbol 12-myristate 13-acetate (PMA)-stimulated EL-4 cells that contained T-cell factors. The PFC response to another TI-2 antigen, TNP-Ficoll, was also significantly enhanced after co-stimulation by P 388-D1 supernatants. The response to TI-2 antigens being macrophage dependent, the influence of supernatants of peritoneal macrophages from male and female F1 hybrids incubated with TNP-Ficoll on the PFC response of normal DBA/2 mouse spleen cells to sheep erythrocytes was assessed. It was found that macrophage supernatants from female hybrids regularly increased by more than two times this anti-SRBC PFC response, whereas macrophage supernatants from male F1 hybrids did not. Moreover, in a specific proliferation test measuring IL-1 activity, when macrophage supernatants from female F1 produced a 13-fold increase of thymidine incorporation, supernatants from male F1 only produced a three-fold increase. It is concluded that, in addition to the known defects of B cells from Xid mice, their macrophages are also defective.
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PMID:Xid mouse lymphocytes respond to TI-2 antigens when co-stimulated by TI-1 antigens or lymphokines. 329 78

The present study was performed to determine whether H-2 matching is required for full cytotoxic T lymphocyte (CTL) responses to allo-H-2 antigens in allogeneic bone marrow chimeric mice. A number of irradiated, bone marrow-reconstituted chimeras constructed from various combinations of marrow cells from B10 H-2 recombinant strains and AKR recipient mice were prepared. Spleen cells obtained from such chimeras and normal control mice were activated in vitro by culturing them with irradiated stimulator cells. It was shown that spleen cells from [4R----AKR], [(4R X 3R)F1----AKR] or [AQR----AKR] chimeras, which were histocompatible on the left hand-side of the H-21 subregion between donor and recipient mice, generated greater CTL activities than those that were seen with spleen cells of [3R----AKR] or [5R----AKR] chimeras, which were histoincompatible in this region. We were unable to demonstrate suppressor cell activity of the spleen cells of [3R----AKR] chimeras cultured with stimulator cells. Although spleen cells from [3R----AKR] chimeras showed substantial proliferative responses to stimulator cells (MLR) and to Con A and LPS, IL2 activities of supernatants from Con A-activated spleen cells (Con A SN) of the chimeras were significantly lower than those of [4R----AKR] or [(4R X 3R)F1----AKR] chimeras. Furthermore, vigorous CTL activities were obtained with either spleen cells or thymocytes from [3R----AKR] chimeras when rat Con A SN was added to the MLR cultures. These observations suggest that the numbers of precursor CTLs in the cells from [3R----AKR] chimeras are at the same level as those of [(4R X 3R)F1----AKR] or normal mice and that the low CTL activities generated by spleen cells of [3R----AKR] chimeras compared to H-2I-matched chimeras are due in large measure to deficiency in IL2 production by the splenic T cells of the [3R----AKR] chimeras.
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PMID:Generation of cytotoxic T lymphocyte responses to allo-H-2 antigens in allogeneic bone marrow chimeras histocompatible at the H-2 subregions. 349 Apr 29

The suppression of in vitro antibody responses by dimethylnitrosamine (DMN) was produced in a mouse hepatocyte and splenocyte co-culture system. Mouse hepatocytes were isolated from female B6C3F1 mice and cultured for 20-24 hr to allow the formation of a monolayer on collagen-coated plastic petri dishes. Spleen cells were isolated from the same hybrid and were co-cultured with the hepatocytes along with DMN. Cyclophosphamide (CP), an immunosuppressive agent requiring metabolic activation that was included as an initial positive control, produced a marked suppression of the in vitro antibody responses to LPS, DNP-Ficoll, and SRBCs in 4 hr in the co-culture system. Under comparable conditions DMN markedly suppressed the response to SRBCs, marginally suppressed the response to DNP-Ficoll, and did not suppress the polyclonal response to LPS. The suppression by DMN was related to the rocking speed during the 4-hr co-culture period and was optimally produced when the cultures were not rocked. Addition of serum into the medium (10% fetal calf serum) during the co-culture period did not change the effects of DMN on the antibody response. However, the addition of extracellular DNA (1 mg calf thymus DNA/ml) prevented the suppression of the antibody response by DMN. These results suggest that DNA represents the primary macromolecular target for the reactive intermediate of DMN, and indicate that a syngeneic co-culture system can be used to characterize the in vitro immunosuppression
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PMID:Suppression of in vitro antibody production by dimethylnitrosamine in mixed cultures of mouse primary hepatocytes and mouse splenocytes. 349 64

Bone marrow and spleen cells obtained from female B6C3F1 mice given a single i.p. exposure to cadmium acetate (0.9 mg/kg), lead acetate (12 mg/kg), or sodium acetate (12 mg/kg), were studied using flow cytometry, immunologic, and hematologic assays. Significant changes were detected in subpopulations of bone marrow cells using multiparameter flow cytometry within 1 day following treatment with cadmium or lead. Bone marrow cells obtained from B6C3F1 mice 5 days after treatment with cadmium or lead were found to have a decreased number of cells expressing Mac-1, 55-7.2, 14.8, and Lyt-1 antigens, suggesting a shift to immature cell types. An increase in the number of progenitor cells (CFU-C) obtained from the bone marrow of mice treated with heavy metals was also noted 5 days after exposure to cadmium or lead. A time-dependent suppression of the in vitro primary humoral immune response of spleen cells to SRBCs, TNP-Ficoll and TNP-LPS was produced by cadmium or lead treatment. Suppression of the mitogenic response of spleen cells to Con A, PHA, and LPS was also found to be time-dependent. Spleen cell surface marker expression (Mac-1, Lyt-1, Lyt-2 and 14.8) was altered in response to cadmium or lead treatments, but these changes did not appear to correlate with the humoral immunity or mitogen-induced proliferation data. These studies demonstrate that changes in cell surface markers on discrete subpopulations of lymphoid cells present in the spleens of heavy metal exposed mice may not correlate with alterations in the functional activity of these cells. However, changes in murine bone marrow surface markers in response to cadmium or lead treatment predicts a shift to immature cell types, which appeared to correlate with the increase in CFU-C activity.
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PMID:Analysis of heavy metal immunotoxicity by multiparameter flow cytometry: correlation of flow cytometry and immune function data in B6CF1 mice. 362 73

Inbred C57BL/6J mice were infected with either Trypanosoma rhodesiense organisms of Walter Reed Army Trypanozoon antigenic type 3 or 5 (WRATat 3 or WRATat 5) or were immunized with soluble trypanosomal antigens. Spleen cells obtained from immunized hosts undergo blastogenesis, measured by thymidine incorporation, when exposed to trypanosomal antigens in vitro. Spleens obtained from mice infected with T. rhodesiense organisms do not respond or respond only minimally to trypanosomal antigens in vitro. Spleen cells of infected mice suppress the trypanosomal antigen-induced proliferative response of spleen cells from immunized mice in co-culture experiments. The suppressive activity was found in both the plastic adherent and plastic nonadherent spleen cell populations. The in vitro responses of normal spleen cells to LPS and Con A were also suppressed by spleen cells obtained from infected mice.
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PMID:Suppression of parasite antigen-specific lymphoid blastogenesis in African trypanosomiasis. 617 Jul

Spleen cells from adult CBA/H or CBA/N mice, or from neonatal CBA/H mice, were fractionated on thin layers of fluorescein (FLU)-gelatin to yield FLU-specific B lymphocytes. A single cell, or small numbers ranging from 1 to 10, were cultured in 10-microliter microcultures together with various antigens and mitogens. The results were compared with those of bulk culture or limiting dilution cultures supported by thymus filler cells. B cell growth and differentiation-promoting conditioned media (BGDA) were added to some cultures. The CBA/N results gave no support to the commonly used classification of T cell-independent (TI) antigens into TI-1 and TI-2 categories. A typical supposed TI-1 antigen, FLU-LPS, strongly stimulated normal adult single FLU-specific B cells to proliferate and form antibody, but virtually failed to trigger CBA/N B cells of comparable antigen-binding avidity. The same was true of LPS or LPS plus dextran sulfate acting as mitogens. The allegedly TI-2 antigen FLU-Ficoll, although still triggering comparatively poor responses, was actually marginally more active than FLU-LPS. FLU-Brucella abortus (FLU-BA) + BGDA gave the best results with single CBA/N B cells, but still induced only 1.27% of cells to develop into antibody-forming clones vs 12.2% with CBA/H cells. The results obtained with single neonatal B cells also lent no support to the distinction between TI-1 and TI-2. Both "TI-1" and "TI-2" stimuli caused adequate proliferation, one "TI-2" antigen stimulating 23.2% of the cells. None of the antigens caused good antibody formation, however, probably because multivalent antigens can deliver signals impeding the differentiation of immature B cells. It is therefore suggested that the classification of TI-1 antigens into two subcategories be abandoned, at least for the time being.
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PMID:A reappraisal of "T-independent" antigens. II. Studies on single, hapten-specific B cells from neonatal CBA/H or CBA/N mice fail to support classification into TI-1 and TI-2 categories. 619 8

Murine splenic B lymphocytes were separated into size-dependent subpopulations by using counterflow centrifugation. Spleen cells were rigorously depleted of T lymphocytes to yield a population of cells that were greater than 90% surface immunoglobulin (Ig)-positive and that had a mean cell volume of 136.6 +/- 3.3 microns. From this population, five fractions of cells were obtained with mean cell volumes that ranged from 115.8 +/- 3.7 microns in fraction 1 to 168.0 +/- 6 microns in fraction 5. The cells in these five subpopulations were characterized by analysis on a fluorescence-activated cell sorter after staining with acridine orange to evaluate RNA and DNA content, and with fluorescein-conjugated anti-mu, anti-delta, and anti-Ia antibodies to evaluate their surface membrane phenotypes. DNA analysis revealed that virtually all of the cells in fractions 1 to 4 had 2 N DNA. Between 7 and 21% of fraction 5 cells were either in S-phase or contained 4 N DNA. In contrast, RNA content increased through the fractions, suggesting a transition from G0 to G1 in the subpopulations with increasing B cell size. As another measure of cell activation seen with increasing cell size, we observed a progressive increase in the expression of surface Ia and a decrease in the expression of surface IgD. In the absence of in vitro stimulation, the larger cells showed significantly higher levels of thymidine incorporation. When polyclonal B cell activators such as LPS or anti-Ig antibody were added, peak proliferative responses were similar in all of the fractions, but the time necessary to achieve a maximal response was shorter for the larger-sized cell subpopulations than it was for the smaller-sized cell subpopulations. Unprimed, size-dependent B lymphocyte subpopulations exhibited spontaneous or "background" antibody formation that occurred primarily in the subpopulations containing the largest cells. T cell factors present in EL4 supernatant enhanced the efficiency of in vitro differentiation of these same subpopulations. When cultured in the absence of T cell help, the thymus-independent type 1 (TI-1) antigen TNP-Brucella abortus (TNP-BA) or the thymus-independent type 2 (TI-2) antigen TNP-Ficoll induced the largest anti-TNP plaque-forming cell (PFC) responses in the fractions containing intermediate-sized cells, suggesting that in vitro, antigen-specific responses came primarily from B cells that have been influenced in vivo to leave their small resting state. The subpopulations containing the smallest size B cells required the presence of both a TI antigen and EL4 supernatant for efficient differentiation.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Size-dependent B lymphocyte subpopulations: relationship of cell volume to surface phenotype, cell cycle, proliferative response, and requirements for antibody production to TNP-Ficoll and TNP-BA. 620 26

In this report we provide evidence that suggests that MOPC 104E may come under regulation in highly immunosuppressed hosts depleted of T cells. Mice that are adult thymectomized, total body irradiated, and transplanted with bone marrow cells were able to resist the growth of MOPC 104E cells. Spleen cells from such animals had low NK activity and no cytotoxicity against MOPC 104E, and poor response to Con A, PHA, and LPS. The animals were deficient in Lyt-1+ and Lyt-2+ cells. The growth of MOPC 104E cells was measured by using the circulating level of MOPC 104E IgM in vivo in mice treated by different modalities. We observed that inhibition of tumor growth in vivo varied with the treatment of the host. Growth was inhibited in the host in the following order: ATXBM greater than XBM greater than NORMAL greater than ATx mice.
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PMID:Inhibition of growth of MOPC 104E cells in immunosuppressed mice. 638 85

Male (A/Ph and C3H/Cbi/BOM) mice were used in our experiments. The cell-free supernatants of spleen mixed leucocyte cultures and allogeneic brain cortex cells were collected upon short-term incubation and tested in a comparative study. Spleen and brain low molecular factors were fractionated (ultrafiltration and gel column chromatography) and assayed for their activity in mitogen-induced 3H-thymidine incorporation into spleen lymphocytes. The specific release of the allogeneic spleen fraction (ASF-2) has been observed. A non-specific stimulating effect of ASF-2 on PHA- and LPS-activated spleen lymphocytes was shown. In contrast, a non-specific suppressive effect of brain fraction on PHA- and LPS-stimulated lymphocytes was demonstrated. The opposite effects of spleen and brain factors can be connected with their different composition. The lymphocyte cultures were not affected by spleen or brain factor, when cultured without the addition of mitogen. Positive and negative regulation or modulation of triggering events in lymphocyte activation by these factors can be suggested.
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PMID:Effect of low molecular factors released during allogeneic interactions of leucocytes or brain cells on PHA- and LPS-induced DNA synthesis in lymphocytes. 644 24

A cell fusion assay system was devised as a means of measuring cell activation. Polyethylene glycol (PEG) was used to induce fusion between spleen cells of various mouse strains and the BW5147 thymoma cell line. A fusion index (FI) was calculated by determining the ratio of the number of nuclei in fused cells to the number of nuclei in all cells and multiplying by 100 (the FI could range from 0 to 100). Spleen cells from BALB/c mice were compared in PEG-induced fusion assays. BALB/c spleen cells stimulated with phytohemagglutinin, leucoagglutinin, concanavalin A, pokeweed mitogen and LPS showed FI two- to three-fold higher than those found in unstimulated cultures, indicating that stimulated cells fuse at much higher rates. This response is mitogen dose-dependent and parallels DNA synthesis as measured by 3H-TdR incorporation. Treatment of spleen cells with cycloheximide 12 h prior to fusion had no effect on FI. In vivo and in vitro stimulation of BALB/c, C57BL/6 and NZW mice with LPS resulted in enhanced FI. This was not the case in low-responder DBA/2 and nonresponder C3H/HeJ animals.
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PMID:Effect of mitogenic stimulation of murine splenocytes on PEG-induced cell fusion. 667 99


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