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1.
Multicolor flow cytometric analysis for the expression of three effector molecules, i.e., perforin (Per), granzyme A (GraA), and granzyme B (GraB), in human CD8(+) T cells demonstrated that they included five subpopulations, implying the following pathway for the differentiation of CD8(+) T cells: Per(-)GraA(-)GraB(-)-->Per(-)GraA(+)GraB(-)-->Per(low)GraA(+)GraB(-)--> Per(low)GraA(+)GraB(+)-->Per(high)GraA(+)GraB(+). The analysis of the expression of these molecules in the subsets classified by the combination of the expression of CCR7 and CD45RA or by that of CD27, CD28, and CD45RA showed that functional CD8(+) T cell subsets could be partially identified by these phenotypic classifications. However, the functional subsets could be precisely identified by the classification using five cell surface markers or three cell surface markers and three cytolytic molecules. Per(-)GraA(-)GraB(-) and Per(-/low)GraA(+)GraB(-) cells were predominantly found in CCR5(-)CCR7(+) and CCR5(high/low)CCR7(-) subsets, respectively, of CD8(+) T cells expressing the CD27(+)CD28(+)CD45RA(-) phenotype, whereas Per(low)GraA(+)GraB(+) cells were found in the CCR5(low)CCR7(-) subset of those expressing this phenotype and in a part of the CCR5(-/low)CCR7(-) subset of those expressing the CD27(-/low)CD28(-)CD45RA(-/+) phenotype. Ex vivo EBV-specific CD8(+) T cells, which were Per(low/-)GraA(+)GraB(-/+) cells, hardly or very weakly killed the target cells, indicating that these were not effector T cells. These findings suggest that the Per(-)GraA(-)GraB(-), Per(-/low)GraA(+)GraB(-), and Per(low)GraA(+)GraB(+) cells were central memory, early effector memory, and late effector memory T cells, respectively. Per(-/low)GraA(+)GraB(-) cells gained GraB expression after TCR stimulation, indicating that early effector memory T cells could differentiate into late effector and effector T cells. The present study showed the existence of three memory subsets and the pathway for their differentiation.  相似文献   

2.
Introduction of bromine at the 10-position of 3-bromo-8-chloro-benzocycloheptapyridine analogues of type 3 results in formation of atropisomeric compounds of type (+/-)-1 and (+/-)-2 that are easily separable at room temperature on a ChiralPak AD column providing pure atropisomers, (+)-1, (-)-1, and (+)-2, (-)-2, respectively. Evaluation of the FPT activity of these atropisomers revealed that compounds (+)-1 and (+)-2 were more potent in the FPT enzyme and cellular assay than their (-)-isomer counterparts. Compounds (+)-1 and (+)-2 were found to inhibit FPT processing in COS cells at low micro molar range. They were also found to have excellent cellular antitumor activity. Evaluation of compound (+)-1 and (+)-2 in DLD-tumor model in nude mice revealed that they were efficacious, inhibiting tumor growth by 55 and 63% at 50 mpk, respectively.  相似文献   

3.
Six metabolites were obtained as a result of microbial transformation of (+)-nootkatone (1) by the fungal strains: Botrytis, Didymosphaeria, Aspergillus, Chaetomium and Fusarium. Their structure were established as (+)-(4R,5S,7R,9R)-9α-hydroxynootkatone (2), (+)-(4R,5S,7R)-13-hydroxynootkatone (3) and (+)-(4R,5S,7R,9R,11S)-11,12-epoxy-9α-hydroxynootkatone (4), (+)-(4R,5S,7R,11S)-11,12-epoksynootkatone (5), (+)-(4R,5S,7R)-11,12-dihydroxynootkatone (6) and (+)-(4R,5S,7R)-7,11,12-trihydroxynootkatone (7) on the basis of their spectral data. Two products: (4) and (7) were not previously reported in the literature. The antiproliferative activity of (+)-nootkatone (1) and isolated metabolites (2-7) of its biotransformation has been evaluated.  相似文献   

4.
(+)-12alpha-Hydroxysophocarpine (8), a new quinolizidine alkaloid was isolated from the roots of Sophora flavescens, together with 10 known quinolizidine alkaloids, (+)-oxymatrine (1), (+)-matrine (2), (+)-9alpha-hydroxymatrine (3), (+)-allomatrine (4), (+)-oxysophocarpine (5), (-)-sophocarpine (6), (-)-9alpha-hydroxysophocarpine (7), (+)-lehmannine (9), (-)-13,14-dehydrosophoridine (10), and (-)-anagyrine (11). Their structures were elucidated by spectroscopic methods, and the stereochemistry of 8 was confirmed by X-ray analysis. These alkaloids were tested for anti-hepatitis B virus (HBV) activity in vitro, compounds 5, 6, 9, and 10 showed significant anti-HBV activity with inhibitory potency against HBsAg secretion at 48.3-79.3% and that against HBeAg secretion at 24.6-34.6%.  相似文献   

5.
Previous studies of perforin expression and cytokine production in subsets of peripheral human CD45RA(-)CD8(+) T cells with different CD28/CD27 phenotypes showed that CD28(+)CD45RA(-)CD8(+) and CD27(+)CD45RA(-)CD8(+) T cells have characteristics of memory T cells, whereas CD28(-)CD45RA(-)CD8(+) and CD27(-)CD45RA(-)CD8(+) T cells have characteristics of both memory and effector T cells. However, the differentiation pathway from memory CD8(+) T cells into memory/effector CD8(+) T cells has not been completely clarified. We investigated this differentiation pathway using EBV- and human CMV (HCMV)-specific CD8(+) T cells. Three subsets of CD45RA(-)CD8(+) T cells were observed in both total CD8(+) T cells and EBV- or HCMV-specific CD8(+) T cells: CD27(+)CD28(+), CD27(+)CD28(-), and CD27(-)CD28(-). A significant number of the CD27(-)CD28(+) subset was observed in total CD8 T cells. However, this subset was barely detectable in EBV- or HCMV-specific CD8(+) T cells. Analysis of perforin expression and cytotoxic activity in the first three subsets suggested the following differentiation pathway: CD27(+)CD28(+)CD45RA(-)-->CD27(+)CD28(-)CD45RA(-)-->CD27(-)CD28(-)CD45RA(-). This was supported by the observation that the frequency of CCR5(+) cells and CCR7(+) cells decreased during this sequence. Analysis of CCR5 and CCR7 expression in the CD27(+)CD28(+) memory cell subset demonstrated the presence of three CCR5/CCR7 populations: CCR5(-)CCR7(+), CCR5(+)CCR7(+), and CCR5(+)CCR7(-). These findings suggested the following differentiation pathway: CD27(+)CD28(+)CD45RA(-) (CCR5(-)CCR7(+)-->CCR5(+)CCR7(+)-->CCR5(+)CCR7(-))-->CD27(+)CD28(-)CD45RA(-)-->CD27(-)CD28(-)CD45RA(-). The presence of a CD27(-)CD28(+) subset with a CCR5(+)CCR7(-) phenotype implies a specialized role for this subset in the differentiation of CD8(+) T cells.  相似文献   

6.
The ONIOM(B3LYP/6-31G(d):AM1) optimized structures of complexes of diurea calix[4]arene receptor (L) with alkali metals Li(+), Na(+) and K(+) and their complexes with halide ions F(-), Cl(-), Br(-), oxygen-containing anions HCO(3)(-), HSO(4)(-) and CH(3)COO(-) ions were obtained. Binding energies and thermodynamic properties of complex receptors LiL(+), NaL(+) and KL(+) with these anions were determined. The binding stabilities according to binding energies of LiL(+), NaL(+) and KL(+) associated with anions computed either at the ZPVE-corrected ONIOM(B3LYP/6-31G(d):AM1) or BSSE-corrected B3LYP/6-31 + G(d,p)//ONIOM(B3LYP/6-31G(d):AM1) are in the same order: F(-) > CH(3)COO(-) ≈ HCO(3)(-) > Br(-) ≈ HSO(4)(-) ≈ Cl(-). All the receptors LiL(+), NaL(+) and KL(+) were found to be selective toward fluoride ion.  相似文献   

7.
Murine CD4(+)CD25(+) T regulatory (Treg) cells were cocultured with CD4(+)CD25(-) Th cells and APCs or purified B cells and stimulated by anti-CD3 mAb. Replacement of APCs by B cells did not significantly affect the suppression of CD4(+)CD25(-) Th cells. When IL-4 was added to separate cell populations, this cytokine promoted CD4(+)CD25(-) Th and CD4(+)CD25(+) Treg cell proliferation, whereas the suppressive competence of CD4(+)CD25(+) Treg cells was preserved. Conversely, IL-4 added to coculture of APCs, CD4(+)CD25(-) Th cells, and CD4(+)CD25(+) Treg cells inhibited the suppression of CD4(+)CD25(-) Th cells by favoring their survival through the induction of Bcl-2 expression. At variance, suppression was not affected by addition of IL-13, although this cytokine shares with IL-4 a receptor chain. When naive CD4(+)CD25(-) Th cells were replaced by Th1 and Th2 cells, cell proliferation of both subsets was equally suppressed, but suppression was less pronounced compared with that of CD4(+)CD25(-) Th cells. IL-4 production by Th2 cells was also inhibited. These results indicate that although CD4(+)CD25(+) Treg cells inhibit IL-4 production, the addition of IL-4 counteracts CD4(+)CD25(+) Treg cell-mediated suppression by promoting CD4(+)CD25(-) Th cell survival and proliferation.  相似文献   

8.
Previously unreported CD8(+) CD28(-) and CD8(+) CD28(+) T-cell subsets occur in healthy individuals and expand in patients suffering from autoimmune disease. Here we studied, for the first time, the expression of CD8(+) CD28(+) , CD8(+) CD28(-) , and CD8(+) CD56(+) subpopulations in induced sputum from asthmatics. Using sputum samples, purified CD8(+) T cells were stained for surface antigen CD28, CD56, FITC-conjugated anti-perforin, and anti-IFN-gamma. Cytotoxic activity was evaluated in a chromium releasing test. Induced sputum CD8(+) CD28(-) T cells were found to be more expanded and expressed low levels of IFN-gamma in severe asthmatics than mild asthma and age-matched healthy controls. The predominance of CD8(+) CD28(-) T cells can be in part explained by the expansion of CD8(+) CD56(+). CD8(+) CD28(-) T cells from severe asthmatics produced high intracytoplasmic perforin and exerted a potent cytotoxic activity. Considering their phenotyping and functional properties, the CD8(+) CD28(-) T-cell subset may constitute an intermediate phenotype in the process of CD8(+) T-cell differentiation of effector-type cells in severe asthmatics. Functional studies showed that CD8(+) CD28(-) T cells had cytotoxic function.  相似文献   

9.
Oxidation of low-density lipoproteins (LDL) promotes the formation of atherosclerotic plaques. Estrogenic compounds (EC) from foods and other natural products, and synthetic estrogenic compounds (SECs) may prevent heart disease by inhibiting LDL oxidation. In the present study, we tested the antioxidant capacities of two phytoestrogens, daidzein (DAI) and genistein (GEN), and four SECs, (+)- and (-)-Z-bisdehydrodoisynolic acid (ZBDDA), and (+)- and (-)-hydroxy-allenoic acid (HAA), on isolated human LDL subjected to oxidation by cupric sulfate. The effects of these estrogenic compounds on the kinetics of conjugated diene formation in LDL undergoing oxidation were evaluated with a lag-time assay with continuous monitoring of absorbance at 234 nm. Lag-time data revealed that (+)-HAA, (-)-HAA, (+)-ZBDDA, and (-)-ZBDDA had similarly stronger antioxidant activities than either GEN or DAI. We also found that (+)-HAA, (-)-HAA, (+)-ZBDDA, and (-)-ZBDDA strongly inhibited the formation of Cu+-induced thiobarbituric acid reactive substances (TBARS) in LDL, and that GEN and DAI were less effective for inhibiting LDL lipid peroxidation. Finally, electrophoretic evaluation suggested that (+)-HAA, (-)-HAA, (+)-ZBDDA, and (-)-ZBDDA protected the apolipoprotein B-100 of LDL against oxidation better than did GEN or DAI. In summary, the four SECs, (+)-HAA, (-)-HAA, (+)-ZBDDA, and (-)-ZBDDA, were more potent antioxidants than the phytoestrogens, DAI and GEN.  相似文献   

10.
We attempted to characterize the phenotype of cells which initiate fibroblastic stromal cell formation (stroma-initiating cells: SICs), precursor cells for fibroblastic stromal cells, based on the expression of cell surface antigens. First, we stained adult murine bone marrow cells with several monoclonal antibodies and separated them by magnetic cell sorting. SICs were abundant in the c-kit(+), Sca-1(+), CD34(+), VCAM-1(+), c-fms(+), and Mac-1(-) populations. SICs were recovered in the lineage-negative (Lin(-)) cells but not the Lin(+) cells. When macrophage colony-stimulating factor (M-CSF) was absent from the culture medium, no stromal colony appeared among the populations enriched in SICs. Based on these findings, the cells negative for lineage markers and positive for c-fms (M-CSF receptor) were further divided on the basis of the expression of c-kit, VCAM-1, Sca-1 or CD34 with a fluorescence-activated cell sorter. SICs were found to be enriched in the Lin(-)c-fms(+)c-kit(low) cells and Lin(-)c-fms(+)VCAM-1(+) cells but not in Lin(-)c-fms(+)Sca-1(+) cells and Lin(-)c-fms(+)CD34(low) cells. As a result, the SICs were found to be present at highest frequency in Lin(-)c-fms(+)c-kit(low)VCAM-1(+) cells: a mean of 64% of the SICs in the Lin(-) cells were recovered in the population. In morphology and several characteristics, the stromal cells derived from Lin(-)c-fms(+)c-kit(low)VCAM-1(+) cells resembled fibroblastic cells. The number of Lin(-)c-fms(+)c-kit(low)VCAM-1(+) cells in bone marrow of mice injected with M-CSF was higher than that in control mice. In this study, we identified SICs as Lin(-)c-fms(+)c-kit(low)VCAM-1(+) cells and demonstrated that M-CSF had the ability to increase the cell population in vivo.  相似文献   

11.
Percentages of activated T cells correlate with HIV-1 disease progression, but the underlying mechanisms are not fully understood. We hypothesized that HLA-DR(+) CD38(+) (DR(+) 38(+)) CD4(+) T cells produce the majority of HIV-1 due to elevated expression of CCR5 and CXCR4. In phytohemagglutinin (PHA)-stimulated CD8-depleted peripheral blood mononuclear cells (PBMC) infected with HIV-1 green fluorescent protein (GFP) reporter viruses, DR(-) 38(+) T cells constituted the majority of CCR5 (R5)-tropic (median, 62%) and CXCR4 (X4)-tropic HIV-1-producing cells (median, 61%), although cell surface CCR5 and CXCR4 were not elevated in this subset of cells. In lymph nodes from untreated individuals infected with R5-tropic HIV-1, percentages of CCR5(+) cells were elevated in DR(+) 38(+) CD4(+) T cells (median, 36.4%) compared to other CD4(+) T-cell subsets (median values of 5.7% for DR(-) 38(-) cells, 19.4% for DR(+) 38(-) cells, and 7.6% for DR(-) 38(+) cells; n = 18; P < 0.001). In sorted CD8(-) lymph node T cells, median HIV-1 RNA copies/10(5) cells was higher for DR(+) 38(+) cells (1.8 × 10(6)) than for DR(-) 38(-) (0.007 × 10(6)), DR(-) 38(+) (0.064 × 10(6)), and DR(+) 38(-) (0.18 × 10(6)) subsets (n = 8; P < 0.001 for all). After adjusting for percentages of subsets, a median of 87% of viral RNA was harbored by DR(+) 38(+) cells. Percentages of CCR5(+) CD4(+) T cells and concentrations of CCR5 molecules among subsets predicted HIV-1 RNA levels among CD8(-) DR/38 subsets (P < 0.001 for both). Median HIV-1 DNA copies/10(5) cells was higher in DR(+) 38(+) cells (5,360) than in the DR(-) 38(-) (906), DR(-) 38(+) (814), and DR(+) 38(-) (1,984) subsets (n = 7; P ≤ 0.031). Thus, DR(+) 38(+) CD4(+) T cells in lymph nodes have elevated CCR5 expression, are highly susceptible to infection with R5-tropic virus, and produce the majority of R5-tropic HIV-1. PBMC assays failed to recapitulate in vivo findings, suggesting limited utility. Strategies to reduce numbers of DR(+) 38(+) CD4(+) T cells may substantially inhibit HIV-1 replication.  相似文献   

12.
Massive infection of memory CD4 T cells is a hallmark of early simian immunodeficiency virus (SIV) infection, with viral infection peaking at day 10 postinfection (p.i.), when a majority of memory CD4 T cells in mucosal and peripheral tissues are infected. It is not clear if mononuclear cells from the monocyte and macrophage lineages are similarly infected during this early phase of explosive HIV and SIV infections. Here we show that, at day 10 p.i., Lin(-) HLA-DR(+) CD11c/123(-) CD13(+) CD14(-) macrophages in the jejunal mucosa were infected, albeit at lower levels than CD4 memory T cells. Interestingly, Lin(-) HLA-DR(+) CD11c/123(-) CD13(+) CD14(-) macrophages in peripheral blood, like their mucosal counterparts, were preferentially infected compared to Lin(-) HLA-DR(+) CD11c/123(-) CD13(+) CD14(+) monocytes, suggesting that differentiated macrophages were selectively infected by SIV. CD13(+) CD14(-) macrophages expressed low levels of CD4 compared to CD4 T cells but expressed similar levels of CCR5 as lymphocytes. Interestingly, CD13(+) CD14(-) macrophages expressed Apobec3G at lower levels than CD13(+) CD14(+) monocytes, suggesting that intracellular restriction may contribute to the differential infection of mononuclear subsets. Taken together, our results suggest that CD13(+) CD14(-) macrophages in mucosal and peripheral tissues are preferentially infected very early during the course of SIV infection.  相似文献   

13.
Na(+)-K(+)-2Cl(-) cotransporter abundance and location was examined in the gills of Atlantic salmon (Salmo salar) during seawater acclimation and smolting. Western blots revealed three bands centered at 285, 160, and 120 kDa. The Na(+)-K(+)-2Cl(-) cotransporter was colocalized with Na(+)-K(+)-ATPase to chloride cells on both the primary filament and secondary lamellae. Parr acclimated to 30 parts per thousand seawater had increased gill Na(+)-K(+)-2Cl(-) cotransporter abundance, large and numerous Na(+)-K(+)-2Cl(-) cotransporter immunoreactive chloride cells on the primary filament, and reduced numbers on the secondary lamellae. Gill Na(+)-K(+)-2Cl(-) cotransporter levels were low in presmolts (February) and increased 3.3-fold in smolts (May), coincident with elevated seawater tolerance. Cotransporter levels decreased below presmolt values in postsmolts in freshwater (June). The size and number of immunoreactive chloride cells on the primary filament increased threefold during smolting and decreased in postsmolts. Gill Na(+)-K(+)-ATPase activity and Na(+)-K(+)-2Cl(-) cotransporter abundance increased in parallel during both seawater acclimation and smolting. These data indicate a direct role of the Na(+)-K(+)-2Cl(-) cotransporter in salt secretion by gill chloride cells of teleost fish.  相似文献   

14.
Islam MT  Tahara S 《Phytochemistry》2000,54(8):901-907
The dihydroflavonols, (2R,3S)-(+)-3',5-dihydroxy-4',7-dimethoxydihydroflavonol and (2R,3R)-(+)-4',5,7-trimethoxydihydroflavonol were isolated from the stem bark of Lannea coromandelica, along with the known (2R,3R)-(+)-4',7-di-O-methyldihydroquercetin, (2R,3R)-(+)-4',7-di-O-methyldihydrokaempferol and (2R,3R)-(+)-4'-O-methyldihydroquercetin. All five compounds were isolated for the first time from the genus Lannea; furthermore, (2R,3S)-(+)-3',5-dihydroxy-4',7-dimethoxydihydroflavonol, was a rare cis-type isomer. The structures of all compounds were elucidated by spectroscopic methods including 2D NMR and CD analysis.  相似文献   

15.
A CD30 ligand (CD30L, CD153) is a type II membrane-associated glycoprotein belonging to the TNF family. To illustrate the potential role of CD30L in CD4(+) Th1 cell responses, we investigated the fate of Ag-specific CD4(+) T cells in CD30L-deficient (CD30L(-/-)) mice after Mycobacterium bovis bacillus Calmette-Guérin (BCG) infection. The number of bacteria was significantly higher in organs of CD30L(-/-) mice than in wild-type (WT) mice 4 wk postinfection. The numbers of purified protein derivative- or Ag85B-specific-IFN-gamma-producing-CD4(+) T cells in spleen, lung, or peritoneal exudate cells were significantly fewer in CD30L(-/-) mice than in WT mice. During the infection, CD30L was expressed mainly by CD44(+)CD3(+)CD4(+) T cells but not by CD3(+)CD8(+) T cells, B cells, dendritic cells, or macrophages. Costimulation with agonistic anti-CD30 mAb or coculturing with CD30L-transfected P815 cells restored IFN-gamma production by CD4(+) T cells from BCG-infected CD30L(-/-) mice. Coculturing with CD30L(+/+)CD4(+) T cells from BCG-infected WT mice also restored the number of IFN-gamma(+)CD30L(-/-)CD4(+) T cells. When transferred into the CD30L(+/+) mice, Ag-specific donor CD30L(-/-) CD4(+) T cells capable of producing IFN-gamma were restored to the compared level seen in CD30L(+/+) CD4(+) T cells on day 10 after BCG infection. When naive CD30L(+/+) T cells were transferred into CD30L(-/-) mice, IFN-gamma-producing-CD4(+) Th1 cells of donor origin were normally generated following BCG infection, and IFN-gamma-producing-CD30L(-/-)CD4(+) Th1 cells of host origin were partly restored. These results suggest that CD30L/CD30 signaling executed by CD30(+) T-CD30L(+) T cell interaction partly play a critical role in augmentation of Th1 response capable of producing IFN-gamma against BCG infection.  相似文献   

16.
To investigate the behavior of hematopoietic stem cells (HSCs) in cord blood (CB), we analyzed the expression and function of TIE2, a tyrosine kinase receptor. A subpopulation of Lineage (Lin)(-/low)CD34(+) cells in CB expressed TIE2 (18.8%). Assays for long-term culture-initiating cells (LTC-IC) and cobble-stone formation revealed that Lin(-/low)CD34(+)TIE2(+) cells showed to have a capacity of primitive hematopoietic precursor cells in vitro. When Lin(-/low)CD34(+)TIE2(+) cells were cultured on the stromal cells, they transmigrated under the stromal layers and kept an immature character for a few weeks. By contrast, Lin(-/low)CD34(+)TIE2(-) cells differentiated immediately within a few weeks. Finally, we confirmed that 1x10(4)Lin(-/low)CD34(+)TIE2(+) cells were engrafted in non-obese diabetic/severe combined immunodeficiency (NOD/SCID) mice, while 1x10(4)Lin(-/low)CD34(+)TIE2(-) cells were not. Taken together, we conclude that TIE2 is a marker of HSCs in CB. A ligand for TIE2, Ang-1 promoted the adhesion of sorted primary Lin(-/low)CD34(+)TIE2(+) cells to fibronectin (FN), and this adhesion may play a critical role in keeping HSCs in an immature status under the stromal cells.  相似文献   

17.
18.
In this paper, the preparation of new supported ionic liquids (SILs) composed of the N-methylimidazolium cation and the quinoline cation is described. They have been confirmed and evaluated by infrared spectroscopy, elemental analysis and thermogravimetric analysis. Six kinds of different SILs included SiO(2)·Im(+)·Cl(-), SiO(2)·Im(+)·BF(4)(-), SiO(2)·Im(+)·PF(6)(-), SiO(2)·Qu(+)·Cl(-), SiO(2)·Qu(+)·BF(4)(-) and SiO(2)·Qu(+)·PF(6)(-). The adsorption characteristics of ferulic acid (FA), caffeic acid (CA) and salicylic acid (SA) on SILs were investigated by static adsorption experiments. It was found that SiO(2)·Qu(+)·Cl(-) had excellent adsorption and desorption capacity to three tested phenolic compounds. The dynamic adsorption characteristics of FA, CA and SA on SiO(2)·Qu(+)·Cl(-) were also studied. The saturated adsorption capacity of FA, CA and SA using SiO(2)·Qu(+)·Cl(-) as adsorbent was 64.6 mg/g, 53.2 mg/g and 72.2 mg/g respectively. Using 70% ethanol as eluent, the saturated desorption efficiencies of FA, CA and SA were 97.2%, 90.3% and 96.5% respectively. Thus, SiO(2)·Qu(+)·Cl(-) had strong adsorption and separation capacity for FA, CA and SA.  相似文献   

19.
Although several subsets of intestinal APCs have been described, there has been no systematic evaluation of their phenotypes, functions, and regional localization to date. In this article, we used 10-color flow cytometry to define the major APC subsets in the small and large intestine lamina propria. Lamina propria APCs could be subdivided into CD11c(+)CD11b(-), CD11c(+)CD11b(+), and CD11c(dull)CD11b(+) subsets. CD11c(+)CD11b(-) cells were largely CD103(+)F4/80(-) dendritic cells (DCs), whereas the CD11c(+)CD11b(+) subset comprised CD11c(+)CD11b(+)CD103(+)F4/80(-) DCs and CD11c(+)CD11b(+)CD103(-)F4/80(+) macrophage-like cells. The majority of CD11c(dull)CD11b(+) cells were CD103(-)F4/80(+) macrophages. Although macrophages were more efficient at inducing Foxp3(+) regulatory T (T(reg)) cells than DCs, at higher T cell/APC ratios, all of the DC subsets efficiently induced Foxp3(+) T(reg) cells. In contrast, only CD11c(+)CD11b(+)CD103(+) DCs efficiently induced Th17 cells. Consistent with this, the regional distribution of CD11c(+)CD11b(+)CD103(+) DCs correlated with that of Th17 cells, with duodenum > jejunum > ileum > colon. Conversely, CD11c(+)CD11b(-)CD103(+) DCs, macrophages, and Foxp3(+) T(reg) cells were most abundant in the colon and scarce in the duodenum. Importantly, however, the ability of DC and macrophage subsets to induce Foxp3(+) T(reg) cells versus Th17 cells was strikingly dependent on the source of the mouse strain. Thus, DCs from C57BL/6 mice from Charles River Laboratories (that have segmented filamentous bacteria, which induce robust levels of Th17 cells in situ) were more efficient at inducing Th17 cells and less efficient at inducing Foxp3(+) T(reg) cells than DCs from B6 mice from The Jackson Laboratory. Thus, the functional specializations of APC subsets in the intestine are dependent on the T cell/APC ratio, regional localization, and source of the mouse strain.  相似文献   

20.
The copper/chiral phosphoramidite (L(1))-catalyzed conjugate addition of dimethylzinc to cycloocta-2,7-dienone 4, followed by the methylation of the intermediate enolate, yielded a single isomer of 7,8-dimethylcyclooct-2-enone (+)-5. Compound (+)-5 was subjected to the second conjugate addition with ent-L(1) giving only one stereoisomer of 2,3,7-trimethylcyclooctanone (+)-6, which was converted to 2,3,7-trimethylcyclooctanol 7. To determine the relative and absolute configurations of these compounds, the (1)H NMR anisotropy method using (S)-(+)-2-methoxy-2-(1-naphthyl)propionic acid {(S)-(+)-MalphaNP acid} 1 was applied. Racemic alcohol (+/-)-7 was esterified with (S)-(+)-MalphaNP acid 1 yielding diastereomeric esters, which were efficiently separated by HPLC on silica gel affording the first-eluted MalphaNP ester (-)-10a and the second-eluted one (-)-10b. The relative and absolute configurations of ester (-)-10a were determined to be (S;1R,2S,3R,7S) by analyzing the (1)H and (13)C NMR spectra of (-)-10a and (-)-10b, especially their HSQC-TOCSY and NOESY spectra, and by applying the MalphaNP anisotropy method. The alcohol 7 formed from (+)-6 was similarly esterified with (S)-(+)-MalphaNP acid 1 yielding an MalphaNP ester, which was identical with (-)-10a, and the relative and absolute configurations of 2,3,7-trimethylcyclooctanone (+)-6 were determined to be (2S,3R,7S).  相似文献   

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