Search results for "spleen"

Frequency of cytotoxic T lymphocyte precursors to herpes simplex virus type 1 as determined by limiting dilution analysis.

1983

The conditions for establishing a limiting dilution assay to measure cytotoxic T lymphocyte precursors (CTL-P) against herpes simplex virus type 1 (HSV-1) were determined. Analysis by Poisson statistics demonstrated that the estimated frequency of HSV-1-reactive cells in the spleens of normal mice was less than 1/250,000. In contrast, mice immunized previously with infectious HSV-1 demonstrated a CTL-P frequency between 1/3,500 and 1/15,670. The generation of a maximum cytotoxic T lymphocyte response required that mice be primed in vivo with infectious virus. Immunization with inactivated virus either failed to elicit detectable CTL-P frequencies or gave frequencies markedly less than thos…

Fine specificity and cytolytic activity of continuously growing alloreactive cytotoxic T lymphocyte clones.

1980

The role of Lyt 1+ T-cell-derived secondard CTL inducing factor allowed the cloning of alloreactive cytotoxic T lymphocytes (CTL) by the limiting dilution approach. Several monoclonal cell lines were established in vitro. The lytic activity of some of the cell lines exceeded that of CTL from bulk cultures; that is, 50% of the target cells were lysed at an effector to target cell ratio of 0.04:1. The fine specificity of individual CTL clones is discussed.

T cell-mediated cytotoxic immune responsiveness of chimeric mice bearing a thymus graft fully allogeneic to the graft of lymphoid stem cells

1980

Fully allogeneic, chimeric mice were established by adult thymectomy of (A × B) F1animals, grafting parental A-type thymus under the kidney capsula, followed by lethal (900 rd) irradiation and reconstitution with B parental-type bone marrow cells treated with xenogeneic anti-T cell antiserum plus complement. Following in vivo sensitization with inactivated Sendai virus (SV) suspensions, no virus-specific T cells could be detected within the spleen cells of the mice. Upon stimulation with third-party allogeneic cells in a primary mixed lymphocyte culture, spleen cells of all animals generated alloreactive cytotoxic T lymphocytes (CTL). More interestingly, upon secondary in vitro stimulation …

Impact of thymus on the generation of immunocompetence and diversity of antigen-specific MHC-restricted cytotoxic T-lymphocyte precursors.

1981

How I diagnose and treat splenic lymphomas.

2011

Abstract The incidental finding of an isolated splenomegaly during clinical assessment of patients evaluated for unrelated causes has become increasingly frequent because of the widespread use of imaging. Therefore, the challenging approach to the differential diagnosis of spleen disorders has emerged as a rather common issue of clinical practice. A true diagnostic dilemma hides in distinguishing pathologic conditions primarily involving the spleen from those in which splenomegaly presents as an epiphenomenon of hepatic or systemic diseases. Among the causes of isolated splenomegaly, lymphoid malignancies account for a relevant, yet probably underestimated, number of cases. Splenic lymphoma…

L-Selectin-deficient SJL and C57BL/6 mice are not resistant to experimental autoimmune encephalomyelitis

2008

L-selectin has been suggested to play a role in the pathogenesis of experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis. Here we demonstrate that L-selectin(-/-) SJL mice are susceptible to proteolipid protein (PLP)-induced EAE because the compromised antigen-specific T cell proliferation in peripheral lymph nodes is fully compensated by the T cell response raised in their spleen. Transfer of PLP-specific T cells into syngeneic recipients induced EAE independent of the presence or absence of L-selectin on PLP-specific T cells or in the recipient. Leukocyte infiltration into the central nervous system parenchyma was detectable independent of the mode of dis…

Effects of Indole-3-Carbinol and Flavonoids Administered Separately and in Combination on Nitric Oxide Production and iNOS Expression in Rats

2010

Beneficial effects of natural compounds are often attributed to modulation of NO production; however effects produced by plant extracts do not correlate with effects of purified components. The goal of our work was to study ability of flavonoids and indole-3-carbinol, as well as their combinations to modify NO production, iNOS gene and protein expression in rat tissues. Baicalein and luteolin decreased NO concentration in both intact and LPS-treated animals. Baicalein decreased iNOS gene expression. Luteolin decreased NO production in the liver and heart and number of iNOS-positive cells in the liver of LPS-treated animals. Combination of the two substances did not decrease the NO synthesis…

Immune suppression in advanced chronic fascioliasis: an experimental study in a rat model.

2006

Chronicity and Th2 immune responses are features of helminth infections in humans. The liver fluke promotes its own survival through several strategies to down-regulate the immune response of the host during the early phase of infection. However, there is no evidence that this modulation occurs much later. The immune response in advanced chronic fascioliasis was analyzed in an experimental rat model at 20 weeks after infection. Cytokine quantification in infected rat serum revealed basal levels. The predominant immunoglobulin (Ig) isotype was IgG1. Flow cytometry analysis of T cell (CD3 + , CD4 + , and CD8a + ), B cell (CD45R + ), and macrophage (CD11b + ) populations in spleens showed no s…

Anaemia in advanced chronic fasciolosis

2008

Abstract The association between fasciolosis-induced anaemia and related factors has been quantified in a rodent model. Haematological parameters were analysed in Wistar rats at 20 and 60 weeks post-infection (p.i.). Pigment stones and bile specimens were collected. Serum IgG1, IgG2a and IgE were determined in rat serum samples. Cytokine levels have been correlated with haematological parameters. The screening for gastrointestinal bleeding was carried out. Bacteriological bile cultures revealed viable bacteria in 53.8% of specimens at 60 weeks p.i. The results show that the type of anaemia in fasciolosis might be considered a biomarker of the chronicity period of the disease, changing from …

Expression of a glucocorticoid receptor (DlGR1) in several tissues of the teleost fish Dicentrarchus labrax

2008

Since glucocorticoids have a role in maintaining the homeostatic status in fish, in the present paper mRNA expression (in situ hybridization) and tissue immunohistochemical localization of a glucocorticoid receptor (DlGR1) in several Dicentrarchus labrax organs are reported. Riboprobe and specific antibodies were prepared by using the DlGR1 that has been previously cloned and sequenced from peritoneal cavity leukocytes. Both mRNA and receptor were identified in head kidney, spleen, gills, intestine, heart and liver tissues. The functional roles of DlGR1 localization are discussed.