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81.
The fine-needle aspiration cytologic findings of Wilms' tumor occurring in a 20-yr-old female patient and a 35-yr-old male patient showing blastemal, spindled sarcomatous and rare epithelial components are reported. The male patient had the typical presentation of renal mass with metastasis to lung and pleura, whereas the female patient had an unusual presentation with the tumor originated from the subcapsular nephrogenic zone of the kidney, extending into the liver without invasion into the renal cortex. Cytogenetic analysis of this case identified: 90, XXXX, +2x3-4, -5, -15, -16, -17, -17, i (17)(q10) x2. This finding may represent a genetic change associated with Wilms' tumor of older pediatric and young adult patients. To the best of our knowledge, this case is the sixth case with cytogenetic study and the first case revealing isochromosome 17q of an adult Wilms' tumor. 相似文献
82.
Cytokine production in the spleens of mice infected with the protozoan parasite Trypanosoma cruzi was analyzed in three models which differ in the outcome of the infection. Using immunocytochemical techniques to detect cytokine-producing cells, the production of type 1 [interleukin-2 (IL-2) and interferon (IFN)-γ], type 2 (IL-4, IL-5, IL-10), inflammatory [tumor necrosis factor (TNF)-α, IL-1α, IL-6] and regulatory (transforming growth factor-β) cytokines were examined. With the exception of IL-4 and IL-5, cells producing all of the cytokines assayed were detected in both the resistant and susceptible models of T. cruzi infection. Cells producing IL-4 and IL-5 were not detected until later in infection in the resistant mice (>34 days), at about the time animals of the susceptible strain succumb to the infection. Mice of the susceptible model showed a slight delay in the appearance of cells producing the type 1 cytokines IL-2 and IFN-γ and an earlier appearance of TNF-producing cells, in comparison to resistant mice. Cells producing IL-2 or IL-10 were transient in their appearance in the spleen while cells producing IL-1, IL-4, IL-5, IL-6, IFN-γ, TNF, or TGF-β were first detectable in either the acute or post-acute stage of the infection and persisted up to 700 days post infection in two different resistant models of the infection. Cells producing IFN-γ, TNF-α and TGF-β were particularly numerous even very late in the infection. Double-staining techniques were used to show that the vast majority of the IFN-γ-producing cells in the spleen were CD4?, CD8? α/β TCR+ T cells. This study confirms the transience of IL-2 production in the acute stage of T. cruzi infection and the persistent and simultaneous production of type 1 and type 2 cytokines during the late-acute and chronic stages of the infection. Susceptibility or resistance to T. cruzi infection does not associate with a Th2 pattern of cytokine production in the three models examined in this study. The overlapping pattern of type 1 and type 2 cytokine-producing cells in both the acute and chronic stages of T. cruzi infection demonstrates that longterm infections do not necessarily lead to a dominance of either type 1 or type 2 cytokine production. 相似文献
83.
Tomohiro Koga Kunihiro Ichinose Atsushi Kawakami George C. Tsokos 《Expert Review of Clinical Immunology》2019,15(6):629-637
Introduction: Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by autoantibodies production and immune complex deposition with systemic clinical manifestations. Interleukin (IL)-17-producing cells play a crucial role in disease pathogenesis and represent an attractive therapeutic target.
Areas covered: This review provides an update on the possibility of targeting IL-17 in SLE. The rational for this approach as well as currently available and future targets are discussed.
Expert opinion: Although human expression studies and animal models indicate that IL-17 blocking may be a promising therapeutic strategy for SLE, direct evidence for IL-17 inhibition in SLE patients is unavailable. Biologic therapies and small-molecule drugs that target IL-17 production are required for the achievement of a favorable clinical effect in SLE patients. 相似文献
84.
R. Kretz G. Rager 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1990,82(2):271-278
Summary WGA-HRP injections were placed into area 17 close to the border with area 18 of Tupaia belangeri in order to study the callosal connections of the striate area in this animal. Most callosal neurons were found in the striate cortex (57.6–86.9%), some in the extrastriate area 18 (10.6–28.1%), and a few in even more temporal regions (2.5–14.3%). Concerning only the area 17, reciprocal homotopic connections could be observed as a strip along the area 17/18 border. Additionally, heterotopic callosal connections could be seen in regions representing the binocular visual field, especially the lower part. The area 17 cells were mostly located in the supragranular layers II and III (94.1–97.2%). But neurons could also be found in the infragranular layers, especially layer VI (2.6–5.2%) and in layer IV (0.2–1.1%). Homotopic projections were mostly seen in layers IIIc and V. The majority of the supragranular and infragranular neurons are pyramidal cells. However, a newly defined subpopulation of neurons, most probably stellate cells, were discovered forming a band in sublayer IIIc, very close to the layer III/IV border. 相似文献
85.
Complex pattern of Th1 and Th2 activation with a preferential increase of autoreactive Th1 cells in BALB/c mice with proteoglycan (aggrecan)-induced arthritis 总被引:2,自引:0,他引:2
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Holló K Glant TT Garzó M Finnegan A Mikecz K Buzás E 《Clinical and experimental immunology》2000,120(1):167-173
The central role of CD4+ T cells and the balance between T helper (Th) subpopulations in the pathogenesis of autoimmune diseases have been extensively studied. Proteoglycan (aggrecan)-induced arthritis (PGIA) is a murine model for rheumatoid arthritis (RA), which is characterized by a Th1 dominance at the onset of the disease. In addition to CD4+ T cells, antigen-presenting B cells and autoantibodies seem to play an important role in the development and regulation of PGIA. To identify proteoglycan-specific CD4+ T cell subsets and Th1- and Th2-supported antibody isotypes during the progression of PGIA, spleen cells of proteoglycan-immunized BALB/c mice were harvested at different times of immunization, and at different stages of the disease, and their cytokine production and antigen-specific antibody isotype profiles were determined by enzyme-linked immunospot (ELISPOT) assays. Both Th1 and Th2 cytokine-producing cells, with the predominance of IL-4/IL-5-secreting cells, were detected during the prearthritic stage, and a shift toward a Th1 dominance was observed at the time of onset of arthritis. Tissue homogenates of acutely inflamed joints contained significantly higher levels of interferon-gamma than IL-4. The prearthritic period and both the acute and chronic phases of joint inflammation were characterized by IgG1 dominance in the sera and this correlated with the number of IgG1-secreting B cells in the spleen. However, the ratio of autoreactive IgG1/IgG2a-secreting cells decreased in arthritic animals. These results indicate the activation and possible regulatory roles of both Th1 and Th2 subsets in the autoimmune process, with the necessity of a relative increase of autoreactive Th1 cells for the induction of joint inflammation. 相似文献
86.
87.
Type 1 and type 2 tumor infiltrating effector cell subpopulations in progressive breast cancer 总被引:4,自引:0,他引:4
Effector T cells fall into two subpopulations based on cytokine-secretion. Type 1 cells secrete IFN-gamma, whereas type 2 cells secrete IL-4, IL-10, and GM-CSF. NKT cells represent a third subpopulation that secretes similar cytokines and have been associated with immunoregulation. Using the TS/A adenocarcinoma, we assessed the phenotype and kinetics of tumor-infiltrating lymphocytes (TIL) in mice challenged subcutaneously in the mammary region. Flow cytometric analysis shows that T cells do not infiltrate the primary tumor site until days 7-14 following tumor challenge. Both CD4 and CD8 TILs were predominantly CD44(High) and expressed CD25, CD69, and CD95 cell surface activation markers. Activated CD4/CD44(High) TIL numbers reached peak levels at day 21 that precipitously decreased by day 28 whereas corresponding CD8 cell numbers progressively increased, however, at lower levels and with later kinetics. Intracellular cytokine staining showed that greater numbers of IL-4-producing Th2 cells were elicited and with earlier kinetics than that of IFN-gamma-producing Th1 cells. T cells co-expressing DX5 (CD3(+)/DX5(+)) emerged (>21 days), suggesting a recruitment of NK-like T cells at later stages of tumor progression. Moreover, tumors selectively up-regulated TGF-beta, MIF, and IP-10 gene expression at times as early as day 4, with peak levels at day 7 in vivo. Such gene expression remained elevated and correlated with a continued progression in tumor growth suggesting that preferential effector cell recruitment and production of select factors during different stages of tumor maturation may aid in regulating effective endogenous antitumor responses in progressive breast cancer. 相似文献
88.
Toll-like receptors (TLR) are pathogen-associated molecular patterns (PAMPs) recognition receptors that playan important role in protective immunity against infection and inflammation.They act as central integrators ofa wide variety of signals,responding to diverse agonists of microbial products.Stimulation of Toll-like receptorsby microbial products leads to signaling pathways that activate not only innate,but also adaptive immunity byAPC dependent or independent mechanisms.Recent evidence revealed that TLR signals played a determiningrole in the skewing of na(?)ve T cells towards either Th1 or Th2 responses.Activation of Toll-like receptors alsodirectly or indirectly influences regulatory T cell functions.Therefore,TLRs are required in both immuneactivation and immune regulation.Study of TLRs has significantly enhanced our understanding of innate andadaptive immune responses and provides novel therapeutic approaches against infectious and inflammatorydiseases.Cellular & Molecular Immunology.2004;1(4):239-246. 相似文献
89.
Immune regulation by novel costimulatory molecules 总被引:10,自引:0,他引:10
CD4 helper T (Th)-cells and the cytokines that they produce play essential regulatory roles in immune and autoimmune responses.
Th activation and differentiation is regulated by costimulatory receptors. CD28 and CTLA-4 are important in maintaining the
threshold of T-cell activation. ICOS and PD-1 are novel costimulatory receptors expressed on activated T-cells. B7-H3 recognizes
a putative costimulatory receptor on activated T-cells. Here we summarize the latest developments in the novel costimulatory
molecules and their roles in regulating Th activation, differentiation, and function. 相似文献
90.
The distributions of retrograde labeled cells in fields 17 and 18 and the fields 17/18 transitional zone were studied in both hemispheres of cats after microiontophoretic administration of horseradish peroxidase into individual cortical columns in fields 17, 18, 19, and 21a. The clustered organization of the internal connections of the cortical fields, the asymmetrical locations of labeled callosal cells relative to the injected columns, and the defined distribution of labeled cells in layers A of the lateral geniculate body suggested that eye-specific neuronal connections support binding of the visual hemifields separately for each eye. Application of marker to columns in fields 19 or 21a demonstrated disparate inputs from fields 17 and 18 and the fields 17/18 transitional zone. It is suggested that these connections may support the extraction of loci and stereoscopic boundaries located in the central sectors of the visual space.Translated from Rossiiskii Fiziologicheskii Zhurnal imeni I. M. Sechenova, Vol. 89, No. 10, pp. 1281–1290, October, 2003. 相似文献