搜索结果: 'methocult media formulations for mouse hematopoietic cells serum containing'

BACKGROUND: Conventional regulatory T cells (Tregs) can suppress human immunodeficiency virus type 1 (HIV-1)-specific immune responses but cannot control immune activation in primary HIV infection. Here,we characterized Treg subsets,using recently defined phenotypic delineation,and analyzed the relative contribution of cell subsets to the production of immunosuppressive cytokines in primary HIV infection. METHODS: In a longitudinal prospective study,ex vivo phenotyping of fresh peripheral blood mononuclear cells from patients with primary HIV infection was performed at baseline and month 6 of follow-up to characterize Treg subsets,immune activation,and cytokine production in isolated CD4(+) T cells. RESULTS: The frequency of CD4(+)CD25(+)CD127(low) Tregs and the distribution between the naive,memory,and activated/memory Treg subsets was similar in patients and healthy donors. However,Tregs from patients with primary HIV infection showed peculiar phenotypic profiles,such as elevated FoxP3,ICOS,and CTLA-4 expression,with CTLA-4 expression strikingly increased in all Treg subsets both at baseline and month 6 of follow-up. The great majority of interleukin 10 (IL-10)-producing CD4(+) T cells were FoxP3(neg) (ie,Tr1-like cells). In contrast to conventional Tregs,Tr1-like cells were inversely correlated with immune activation and not associated with lower effector T-cell responses. CONCLUSION: FoxP3(neg) Tr1-like cells-major contributors to IL-10 production-may have a beneficial role by controlling immune activation in early HIV infection. View Publication

IL-27 is formed by the association of a cytokine subunit,p28,with the soluble cytokine receptor EBV-induced gene 3 (EBI3). The IL-27R comprises gp130 and WSX-1. The marked difference between EBI3(-/-) and WSX-1(-/-) mice suggests that p28 has functions independent of EBI3. We have identified an alternative secreted complex formed by p28 and the soluble cytokine receptor cytokine-like factor 1 (CLF). Like IL-27,p28/CLF is produced by dendritic cells and is biologically active on human NK cells,increasing IL-12- and IL-2-induced IFN-gamma production and activation marker expression. Experiments with Ba/F3 transfectants indicate that p28/CLF activates cells expressing IL-6Ralpha in addition to the IL-27R subunits. When tested on CD4 and CD8 T cells,p28/CLF induces IL-6Ralpha-dependent STAT1 and STAT3 phosphorylation. Furthermore,p28/CLF inhibits CD4 T cell proliferation and induces IL-17 and IL-10 secretion. These results indicate that p28/CLF may participate in the regulation of NK and T cell functions by dendritic cells. The p28/CLF complex engages IL-6R and may therefore be useful for therapeutic applications targeting cells expressing this receptor. Blocking IL-6R using humanized mAbs such as tocilizumab has been shown to be beneficial in pathologies like rheumatoid arthritis and juvenile idiopathic arthritis. The identification of a new IL-6R ligand is therefore important for a complete understanding of the mechanism of action of this emerging class of immunosuppressors. View Publication

Helminthic infections modulate host immunity and may protect their hosts from developing immunological diseases like inflammatory bowel disease. Induction of regulatory T cells (Tregs) may be an important part of this protective process. Heligmosomoides polygyrus bakeri infection also promotes the production of the regulatory cytokines TGF-beta and IL-10 in the gut. In the intestines,TGF-beta helps induce regulatory T cells. This study used Foxp3/IL-10 double reporter mice to investigate the effect of TGF-beta on the differentiation of colon and mesenteric lymph node-derived murine Foxp3- IL-10- CD4+ T cells into their regulatory phenotypes. Foxp3- IL-10- CD4+ T cells from H. polygyrus bakeri-infected mice,as opposed to T cells from uninfected animals,cultured in vitro with TGF-beta and anti-CD3/CD28 mAb differentiated into Foxp3+ and/or IL-10+ T cells. The IL-10-producing T cells nearly all displayed CD25. Smad7 is a natural inhibitor of TGF-beta signaling. In contrast to gut T cells from uninfected mice,Foxp3- IL10- CD4+ T cells from H. polygyrus bakeri-infected mice displayed reduced Smad7 expression and responded to TGF-beta with Smad2/3 phosphorylation. The TGF-beta-induced Tregs that express IL-10 blocked colitis when transferred into the Rag/CD25- CD4+ T cell transfer model of inflammatory bowel disease. TGF-beta had a greatly diminished capacity to induce Tregs in H. polygyrus bakeri-infected transgenic mice with constitutively high T cell-specific Smad7 expression. Thus,infection with H. polygyrus bakeri causes down-modulation in Smad7 expression in intestinal CD4+ T cells,which allows the TGF-beta produced in response to the infection to induce the Tregs that prevent colitis. View Publication

Both innate and adaptive immune systems are considered important for cancer prevention,immunosurveillance,and control of cancer progression. It is known that,although both systems initially eliminate emerging tumor cells efficiently,tumors eventually escape immune attack by a variety of mechanisms,including differentiation and recruitment of immunosuppressive CD11b(+)Gr-1(+) myeloid suppressor cells into the tumor microenvironment. However,we show that CD11b(+)Gr-1(+) cells found in ascites of epithelial ovarian cancer-bearing mice at advanced stages of disease are immunostimulatory rather than being immunosuppressive. These cells consist of a homogenous population of cells that morphologically resemble neutrophils. Moreover,like dendritic cells,immunostimulatory CD11b(+)Gr-1(+) cells can strongly cross-prime,augmenting the proliferation of functional CTLs via signaling through the expression of costimulatory molecule CD80. Adoptive transfer of these immunostimulatory CD11b(+)Gr-1(+) cells from ascites of ovarian cancer-bearing mice results in the significant regression of s.c. tumors even without being pulsed with exogenous tumor Ag prior to adoptive transfer. We now show for the first time that adaptive immune responses against cancer can be augmented by these cancer-induced granulocyte-like immunostimulatory myeloid (CD11b(+)Gr-1(+)) cells,thereby mediating highly effective antitumor immunity in an adoptive transfer model of immunity. View Publication

NK cell transcript 4 (NK4),now denoted as IL-32,was originally identified as a transcript whose expression was increased in activated NK cells. It has been very recently demonstrated that NK4 is secreted from several cells upon the stimulation of some inflammatory cytokines such as IL-18,IL-1beta,IFN-gamma and IL-12. Furthermore,NK4 induces production of tumor necrosis factor,macrophage inflammatory protein (MIP)-2 and IL-8 in monocytic cell lines,indicating that this factor would be involved in the inflammatory responses. Based on these findings,NK4 was renamed IL-32. However,the biological activities of IL-32 on other cell types remained undetermined. Furthermore,it was still argued whether IL-32 acts on cells from outside or inside the cells. In this article,we first report that expression of IL-32 was up-regulated in activated T cells and NK cells,and that IL-32beta was the predominantly expressed isoform in activated T cells. IL-32 was specifically expressed in T cells undergoing apoptosis and enforced expression of IL-32-induced apoptosis,whereas its down-regulation rescued the cells from apoptosis in HeLa cells. IL-32 existing in the supernatant would be derived from the cytoplasm of apoptotic cells. These results strongly indicated that IL-32 would be involved in activation-induced cell death in T cells,probably via its intracellular actions. Our present findings expand our understanding of the biological function of IL-32 and argue that IL-32 may act on cells,not only from the outside but also from the inside. View Publication

T-cell genome engineering holds great promise for cell-based therapies for cancer,HIV,primary immune deficiencies,and autoimmune diseases,but genetic manipulation of human T cells has been challenging. Improved tools are needed to efficiently knock out" genes and "knock in" targeted genome modifications to modulate T-cell function and correct disease-associated mutations. CRISPR/Cas9 technology is facilitating genome engineering in many cell types� View Publication

T cells can be re-directed to kill cancer cells using chimeric antigen receptors (CARs) or T cell receptors (TCRs). This approach,however,is constrained by the rarity of tumor-specific single antigens. Targeting antigens also found on bystander tissues can cause life-threatening adverse effects. A powerful way to enhance ON-target activity of therapeutic T cells is to engineer them to require combinatorial antigens. Here,we engineer a combinatorially activated T cell circuit in which a synthetic Notch receptor for one antigen induces the expression of a CAR for a second antigen. These dual-receptor AND-gate T cells are only armed and activated in the presence of dual antigen tumor cells. These T cells show precise therapeutic discrimination in vivo-sparing single antigen bystander" tumors while efficiently clearing combinatorial antigen "disease" tumors. This type of precision dual-receptor circuit opens the door to immune recognition of a wider range of tumors. VIDEO ABSTRACT." View Publication