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1.
Li C Yu L Liu Z Zhu L Hu Y Zhu M Zhu X Shi Y Meng S 《Cellular & molecular biology letters》2006,11(4):449-460
The aim of this study was to construct and evaluate the immunity efficacy of the DNA multivalent vaccine pVIVO2SjFABP-23. The vaccine was constructed and produced as follows. Forty BALB/c mice were divided into four groups designated
pVIVO2, pVIVO2Sj23, pVIVO2SjFABP and pVIVO2SjFABP-23. Each mouse was immunized with 100 μg of the corresponding plasmid DNA by intramuscular injection. 28 days post-vaccination,
the mice were challenged with S. japonicum cercariae, and the worm and egg burdens were determined 42 days post-challenge. Serum samples were collected from all the
mice before and after vaccination and at the end of the experiment, and used for antibody detection. The IFN-γ and IL-4 levels
were quantified in the supernatants of specifically stimulated spleen cells. The number of worms was reduced by 52%, 40% and
42% in mice respectively immunized with pVIVO2SjFABP-23, pVIVO2Sj23 or pVIVO2SjFABP. A respective 61%, 38% and 39% egg reduction was determined relative to those mice that only received the empty pVIVO2
plasmid. pVIVO2SjFABP-23 immunization increased IgG levels against SWAP and SEA. Increased IFN-γ levels were detected in the supernatant
of specific stimulated spleen cells from mice immunized with the 3 different constructs. The multivalent DNA vaccine developed
induced higher levels of protection than the two monovalent tested vaccines. 相似文献
2.
Estefânia Mara do Nascimento Martins Bernardo Sgarbi Reis Maria Aparecida de Resende Antero Silva Ribeiro de Andrade Alfredo Miranda Goes 《Mycopathologia》2009,168(2):51-58
Paracoccidioides brasiliensis is the agent of paracoccidioidomycosis, the most prevalent mycosis in Latin America. Up to the moment no vaccine has been
reported. The aim of this study was to evaluate the influence of the number of immunizations on the protection elicited by
radioattenuated yeast cells of P. brasiliensis. BALB/c mice were divided into two groups that were immunized once (Group 1) or twice (Group 2), respectively. In each group,
mice were divided into sub-groups that were challenged 30, 45, or 60 days after the second immunization. Organ colony-forming
units (CFUs) was determined 90 days post-challenge. A significant reduction in CFUs recovery was verified in both groups,
but it was higher in Group 2. Histologic alterations were observed only in Group 1. The cytokines IL-4, IL-10, and IFN-γ were
produced in mice of Group 1. In Group 2, only IFN-γ was significantly detected. IgG2a predominance relative to IgG1 was also
observed in Group 2. Altogether, our results indicated that mice immunized once developed a mixed Th1/Th2 response, which
was less efficient in the infection control, while a trend to a Th1 pattern was obtained with two immunizations, promoting
optimal elimination of P. brasiliensis yeast cells from mice tissues. 相似文献
3.
Castro-Matteotti B Vera-Cabrera L Ocampo-Candiani J Rendón A Salinas-Carmona MC Welsh O 《Mycopathologia》2008,165(3):127-134
The ability of culture-filtrate proteins to induce a cellular immune response in infected mice and humans was investigated.
A crude extract culture filtrate of Nocardia brasiliensis (CFA) and five semi-purified CFA fractions (P1, P2, P3, P4, P5) were used to stimulate BALB/c mice spleen-cell cultures.
The animals were divided into three groups: the first group was infected with 1 × 107 CFU of N. brasiliensis in the footpad, the second group was immunized with heat-killed bacteria, and the third was injected with sterile saline.
IFN-γ, IL-1α, and IL-4 concentrations were determined in culture supernatants. Protein fractions eliciting IFN-γ production
in mice, as well as the CFA, were used to stimulate IFN-γ production and in vitro cell proliferation assays with peripheral
blood mononuclear cells of patients with actinomycetoma by N. brasiliensis, individuals with pulmonary tuberculosis, and healthy controls. In mice, CFA and three of the protein fractions (P3, P4 and
P5) induced significant IFN-γ production in the infected group. In humans, only the CFA-induced IFN-γ production and cell
proliferation in the group of patients with actinomycetoma. There was no stimulation in tuberculosis patients nor healthy
controls. These results suggest that some culture-filtrate antigens are recognized by patients with active actinomycetoma
and do not cross-react with M. tuberculosis antigens, being therefore potential candidates to develop a diagnostic test. 相似文献
4.
Yusuke Nakanishi Akira Hosono Yasuhiro Hiramatsu Teiji Kimura Ryo Nakamura Shuichi Kaminogawa 《Cytotechnology》2005,47(1-3):69-77
We demonstrate immunomodulatory effects, especially those involving murine intestinal IgA secretion, in Peyer's patch cells
following oral administration of Bifidobacterium immunomodulator (BIM) derived from sonicated B. pseudocatenulatum 7041. BALB/c mice were administered BIM orally for 7 consecutive days. The PP cells demonstrated upregulated secretion of
total IgA including BIM-specific IgA following BIM administration. In observing the response of PP cells co-cultured with
BIM, we found enhanced secretion of interferon-γ (IFN-γ) and interleukin (IL)-6 in the CD4+ T cells. In contrast, IL-12 secretion by Thy1.2− PP cells was enhanced, but secretion of IFN-γ, IL-5, and IL-6 was not significantly affected. Furthermore, the population
of CD4+ CD45RBhigh T cells in PP increased following oral administration of BIM. These data suggest that CD4+ T cells were affected by BIM administration. Overall, the results show that oral administration of BIM induced CD4+ PP cells to change their expression of cell surface antigen and cytokine production. 相似文献
5.
6.
E. Arefian T. Bamdad H. Soleimanjahi M. R. Akhoond M. Parsania A. Ghaemi 《Molecular Biology》2009,43(3):388-393
The vast majority of the world’s population is infected with Herpes simplex virus (HSV). Although antiviral therapy can reduce the incidence of reactivation and asymptomatic viral shedding and limits morbidity
and mortality from active disease, it cannot cure infection. Therefore, the development of an effective vaccine is an important
global health priority. In this study, the induction of IFN-γ production was compared in different herpes simplex virus 1
(HSV-1) vaccines. Glycoprotein D (gD1) as a major immunogenic HSV-1 glycoprotein was chosen to our study. Balb/c mice were administered with DNA vaccine encoding gD1, subunit glycoprotein vaccine
including insect cells infected by a gD1 recombinant Baculovirus, prime DNA vaccine boosted by subunit glycoprotein vaccine, inactivated KOS strain as a positive control, pcDNA3 plasmid and Sf9 cells as negative controls. Evaluation tests showed that the amount
of IFN-γ mRNA at 8, 16 and 32 hours after restimulation sharply decreased whereas, the IFN-γ protein level is significantly
increased. Our results revealed that at 14 days after immunization IFN-γ secretion of stimulated cells in all of the vaccinated
groups dramatically raised rather than secreted IFN-γ levels in mice that were analyzed at 7 days after vaccination. In comparison
to other groups; Prime-Boost immunization dramatically caused vigorous and prompt IFN-γ production at 7 days after immunization
and 8 hours after restimulation.
The article is published in the original. 相似文献
7.
Wu L Zhao L Zheng Q Shang F Wang X Wang L Lang B 《Molecular and cellular biochemistry》2006,284(1-2):65-71
Phosphoenolpyruvate carboxykinase (PEPCK) catalyzes guanosine or adenosine mononucleotide-dependent reversible conversion of oxaloacetate (OAA) and phosphoenolpyruvate (PEP). Mycobacterium (M) tuberculosis possesses a putative GTP-dependent PEPCK. To analyze the immune responses caused by PEPCK, the effects of PEPCK on the induction of CD4+ T cells and cytokines such as IFN-γ, IL-12 and TNF-α were evaluated in mice. It was found that the number of CD4+ T cells was increased in the PEPCK immunized mice although the change of the number of CD8+ T cells was not significant. The cytokines IFN-γ, IL-12 and TNF-α were increased significantly in the mice immunized with PEPCK than those of incomplete adjuvant. These characteristics were further demonstrated in the mice infected by pckA mutated BCG strain. The results indicate that PEPCK can effectively induce cell-mediated immune response by increasing activity of cytokines and PEPCK may be a promising new subunit vaccine candidate for tuberculosis. 相似文献
8.
Pavanelli WR Kaminami MS Geres JR Sano A Ono MA Camargo IC Itano EN 《Mycopathologia》2007,163(3):117-128
Paracoccidioidomycosis (PCM) is a granulomatous disease caused by a dimorphic fungus, Paracoccidioides brasiliensis. The present study investigated the protective activity of the P. brasiliensis high-molecular-mass (hMM) fraction (~380 kDa) in experimental murine PCM. In the first step, lymphocyte proliferation and
production of IFNγ (but not IL-4) were observed in “in vitro” spleen cells (from female BALB/c mice infected (i.v.) with P. brasiliensis) that were stimulated with hMM fractions. In the second step, female BALB/c mice were previously immunized (s.c.) with hMM
fraction (25 μg/protein = F-25 and 50 μg/protein = F-50), and the colony-forming units (CFU) of the lung and spleen, the histopathological
characteristics of the granulomatous lesions, and plasmatic gp43 soluble antigens and anti-hMM IgG levels were analyzed at
28 and 56 days after infection. The lung and liver CFU were lower in mice previously immunized with the hMM fraction (P < 0.05). The granulomatous lesions revealed a greater degree of compaction and organization, with no dissemination of the
fungus to other organs. Lower soluble antigen levels (P < 0.05) and higher IgG anti-hMM fraction (P < 0.05) were observed in immunized groups. The results for CFU, histopathology and antigenemia suggest that the hMM fraction
has a protective effect in experimental paracoccidioidomycosis in BALB/c mice. 相似文献
9.
Hemanta Koley Soumik Barman Nivedita Roy Dhira Rani Saha Ranajit Kumar 《World journal of microbiology & biotechnology》2009,25(4):679-686
In our earlier studies, we constructed a hybrid strain of Shigella dysenteriae type 1 by introducing a plasmid vector pPR 1347. After introduction of a lipopolysaccharide (LPS) biosynthesis gene, virulent
Shigella dysenteriae type 1 strain became avirulent. In our present study, we have evaluated the immune response and protective efficacy of avirulent
live transconjugant Shigella hybrid (LTSH) strain against wild type Shigella dysenteriae type 1, after four doses of oral (rabbit) and intranasal (mouse) immunizations. Serum IgG titers showed exponential increase
during immunization and peaking on the 28th day and remained at that level till the 35th day in both the rabbit and the mouse
models. When tested, serum IgG titers persisted for 63 days in mice and relatively high for 150 days in case of rabbits. Protection
studies showed 100% protection against the challenge with wild type Shigella dysenteriae type 1 strain in rabbits and 80% protection in mice. Our results suggested that the LTSH strain could be a useful vaccine
candidate strain in the future. 相似文献
10.
Kumar S Balakrishna K Agarwal GS Merwyn S Rai GP Batra HV Sardesai AA Gowrishankar J 《Antonie van Leeuwenhoek》2009,95(1):91-100
The PhoP-PhoQ two-component system of Yersinia pseudotuberculosis, a Gram-negative enteric pathogen which causes a variety of gastrointestinal and extraintestinal infections in humans, has
been shown to be necessary for virulence. A phoP-phoQ null mutant of a strain of Y. pseudotuberculosis cured of its native plasmid pYV was obtained and studied for generation of immune response in mouse model following intravenous
inoculation. The phoP-phoQ null mutant elicited much weaker IgG antibody response to whole cell sonicated (WCS) antigen, in particular that of IgG2a
isotype. Interferon-γ levels were also significantly reduced in cultured splenocytes of mice immunized with phoP-phoQ null mutant. The null mutant was found to be about 72-fold less virulent than the parent isogenic strain of Y. pseudotuberculosis. Average counts in spleen of mice inoculated with the null mutant were observed to reduce by at least four logs when compared
with the counts in the spleen of mice inoculated with parent isogenic strain. We can thus suggest that the Th1-type immune
response of the phoP-phoQ null mutant of Y. pseudotuberculosis is diminished in mice. 相似文献
11.
Effect of interferon-γ on the susceptibility to Fas (CD95/APO-1)-mediated cell death in human hepatoma cells 总被引:9,自引:0,他引:9
Shin EC Shin WC Choi Y Kim H Park JH Kim SJ 《Cancer immunology, immunotherapy : CII》2001,50(1):23-30
Many tumors, including hepatocellular carcinomas (HCCs), resist Fas-mediated cell death, which is one of the effector mechanisms
in the host's anti-tumor response; however, this resistance can be abolished by interferon-γ (IFN-γ). IFN-γ may sensitize
Fas-mediated cell death in several ways, but the exact mechanism in HCCs is uncertain. In this study, we thoroughly investigated
the effect of IFN-γ on the susceptibility of one human normal liver cell line and 12 HCC cell lines to Fas-mediated cell death.
We also investigated the effect of IFN-γ on the expression of various apoptosis-related genes such as the Fas/TNF-related
genes, the bcl-2 family, and the caspase family of genes. Although most cell lines showed considerable constitutive expression of Fas, all
tested cell lines resisted Fas-mediated cell death without IFN-γ. When cells were pretreated with IFN-γ, only three cell lines
were made significantly susceptible to Fas-mediated cell death (SNU-354, SNU-387 and SNU-423); the other 10 cell lines were
not affected. IFN-γ increased the mRNA expression of Fas, TRAIL and caspase-1, and surface Fas was also increased. The strongly
sensitized cell lines (SNU-354, SNU-387 and SNU-423) showed a particularly potent increment in surface Fas after IFN-γ treatment
(increase in surface Fas >1.7-fold). This result enabled us to conclude that a potent increment of surface Fas expression
is a major sensitizing mechanism of IFN-γ. We conclude that IFN-γ cannot play a sensitizing role in most HCC cell lines and
that IFN-γ makes HCC cells susceptible to Fas-mediated cell death through a marked up-regulation of surface Fas in some HCC
cells.
Received: 3 August 2000 / Accepted: 24 November 2000 相似文献
12.
Inflammatory and infectious conditions were simulated in cultures of ras/myc-transformed serum-free mouse embryo (ras/myc SFME) cells, using interferon-gamma (IFN-γ, 100 units/ml) and lipopolysaccharide (LPS, 0.5 μg/ml) co-treatment for 24 h,
to investigate their effects on the expression of inducible nitric oxide synthase (iNOS) mRNA and the production of NO. Aminoguanidine
(AG, 1 mM; an NOS inhibitor) along with IFN-γ and LPS, S-nitroso-N-acetyl-DL-penicillamine (SNAP, 100 μM; an NO donor) and/or (±)-N-[(E)-4-Ethyl-2-[(Z)-hydroxyimino]-5-nitro-3-hexene-1-yl]-3-pyridine carboxamide (NOR4, 100 μM; an NO donor), were also added
to analyze the possible association of NO with matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of metalloproteinase-1
(TIMP-1). Co-treatment of cells with IFN-γ and LPS increased iNOS mRNA expression, NO production, MMP-9 mRNA expression, and
105 kDa MMP-9 production. Additional treatment with the NOS inhibitor AG inhibited NO production, but did not down-regulate
the expression of MMP-9 mRNA or 105 kDa MMP-9. The NO donors SNAP and NOR4 did not affect the expression of MMP-9 mRNA, 105 kDa
MMP-9 or TIMP-1 mRNA. These results suggest that ras/myc SFME cells respond to infectious and inflammatory conditions and can enhance malignancy as cancer cells due to their increased
levels of NO and MMP-9 production, but that NO is not directly associated with MMP-9 in these cells.
H. Yamaguchi and Y. Kidachi contributed equally to this work 相似文献
13.
Highly metastatic ras/myc-transformed serum-free mouse embryo (r/m HM-SFME-1) cells were injected subcutaneously to mice and the effects of Nω-nitro-l-arginine methyl ester (l-NAME) on the tumor progression and pulmonary metastasis were investigated. In addition, production of nitric oxide (NO), matrix
metalloproteinases (MMPs) and tumor necrosis factor-alpha (TNF-α) in the tumor cells and in a mouse macrophage-like cell line,
J774.1 cells, was analyzed. The increase in footpad thickness was significantly smaller in the mice which were fed the l-NAME containing water (4.24 ± 0.39 mg/day/mouse). The number of the tumor cells metastasized to the lungs was smaller in
the l-NAME treated mice, although statistical significance was not found. Co-treatment of r/m HM-SFME-1 cells with interferon-gamma (IFN-γ; 100 U/ml) and lipopolysaccharide (LPS; 0.5 μg/ml) significantly enhanced NO
production, and the presence of l-NAME at 1 mM significantly decreased this response. In r/m HM-SFME-1 cells, MMP-2 was undetectable and MMP-9 was also very little in the basal level, and both MMPs were unaffected
by the IFN-γ and/or LPS treatments, not to mention by the l-NAME treatment. In J774.1 cells, any treatment including LPS appeared to enhance MMP-9 production, however, this upregulation
was not inhibited by the additional presence of l-NAME. Production of TNF-α by J774.1 cells was markedly enhanced with LPS treatment, and this enhancement was significantly
reduced in the presence of l-NAME. These results indicate that the inhibitory effects of l-NAME on the tumor cell progression and pulmonary metastasis could be due to suppression of NO from tumor cells and TNF-α
from macrophages (Mol Cell Biochem, 2007).
Hideaki Yamaguchi and Yumi Kidachi contributed equally to this work. 相似文献
14.
We have previously shown that oral administration of skimmed milk(SM) fermented with Lactobacillus delbrueckii ssp. bulgaricus OLL1073R-1 (OLL1073R-1/SM) to DBA/1 mice inhibited the development of collagen-induced arthritis (CIA). In this study, our
aim was to examine possible mechanisms of inhibiting the development of CIA. We studied the effect of OLL1073R-1/SM on cytokine
secretion from cells of popliteal lymph nodes (lymph node cells; LNC) of mice. The results showed that feeding OLL1073R-1/SM
inhibited secretion of proinflammatory cytokines such as interferon γ (IFN-γ), interleukin 6 (IL-6), tumor necrosis factor
α (TNF-α) and the chemokine, monocyte chemoattractant protein 1 (MCP-1). The most prominent effect was inhibition of TNF-α.
Secretion of IL-2 and IL-4 were not influenced. Feeding OLL1073R-1/SM inhibited secretion of proinflammatory cytokines produced
by accessory cells, but not T cells. We conclude that CIA may be prevented via down regulation of secretion of proinflammatory
cytokines such as IL-6, TNF-α and IFN-γ, and of the chemokine of MCP-1.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
15.
To determine whether interferon gamma (IFN-γ) can be used as a biomarker of exposure to viral pathogens, 12-week-old BALB/c
mice were injected intraperitoneally with coxsackievirus B3 (CVB3) or coxsackievirus B4 (CVB4) diluted in sterilized phosphate-buffered
saline (PBS). Control mice were injected with PBS only. Four months after viral infection, mouse spleen cells were harvested
and assayed for the release of IFN-γ by memory T cells after in vitro stimulation with viral antigens, phytohemagglutinin (PHA), and PBS, respectively. The level of IFN-γ was examined by an antibody-capture
enzyme-linked immunosorbent assay (ELISA). A marked increase in the level of IFN-γ was observed when memory T cells from CVB3-infected
mice were incubated with CVB3 virus, but not with CVB4 or PBS. Conversely, memory T cells from mice infected by CVB4 were
not stimulated to produce IFN-γ when they were incubated with CVB3 and PBS, but did significantly produce IFN-γ when stimulated
with CVB4. T cells from mice injected with PBS did not release IFN-γ after stimulation with CVB3 or CVB4. However, these T
cells did release IFN-γ after stimulation with PHA. Our results demonstrated that IFN-γ produced by memory T cells is virus-specific
and may have use as a biomarker in viral exposure studies. The results of this study may be extended to the study of infection
by pathogens that are capable of inducing cell-mediated immune response in humans.
Disclaimer: The United States Environmental Protection Agency through its Office of Research and Development funded and managed the
research described here. It has been subjected to Agency’s administrative review and approved for publication. 相似文献
16.
Cho EJ Hwang HJ Kim SW Oh JY Baek YM Choi JW Bae SH Yun JW 《Applied microbiology and biotechnology》2007,75(6):1257-1265
The anti-diabetic activities of the exopolysaccharides (EPS) produced by submerged mycelial culture of two different mushrooms,
Tremella fuciformis and Phellinus baumii, in ob/ob mice were investigated. All the animals were randomly divided into three groups with seven animals in each group: The control
group received 0.9% NaCl solution; the diabetic groups were treated with EPS from T. fuciformis (Tf EPS) and P. baumii (Pb EPS) at the level of 200 mg/kg body weight using an oral zoned daily for 52 days. The plasma glucose levels in the EPS-fed
mice were substantially reduced by about 52% (Tf EPS) and 32% (Pb EPS), respectively, as compared to control mice. The results
of oral glucose tolerance test (OGTT) revealed that both EPS-fed groups significantly increased the glucose disposal after
52 days of EPS treatments. Furthermore, higher food efficiency ratios and reduced blood triglyceride levels were observed
in the EPS-treated groups. Because peroxisome proliferator-activated receptor gamma (PPAR-γ) is indeed a key regulator of
insulin action, we investigated the expression pattern of adipose tissue PPAR-γ messenger RNA (mRNA) and plasma levels of
PPAR-γ. It was revealed that PPAR-γ was significantly activated in response to EPS treatments. The results suggested that
both EPS exhibited considerable hypoglycemic effect and improved insulin sensitivity possibly through regulating PPAR-γ-mediated
lipid metabolism. Our results indicated that two mushroom-derived EPS might be developed as potential oral hypoglycemic agents
or functional foods for the management of non-insulin-dependent diabetes mellitus. 相似文献
17.
Nishijima K Hisatsune T Kato H Kohyama M Kakehi M Hachimura S Kaminogawa S 《Cytotechnology》1997,25(1-3):89-100
Feeding of a whole casein diet, which abolished the αs1-casein-specific proliferation and IFN-γ productivity of CD4+ T cells, did not affect the proliferative response of CD8+ T cells with regard to the antigen dose response, cell dose response, kinetics of the proliferation and epitope specificity,
as well as IFN-γ production. To assess the characteristics of the CD8+ T cells, we established αs1-casein-specific CD8+ T cell clones from both casein-fed and control mice. The established clones produced different amount of IFN-γ and IL-10,
and one clone derived from the casein-fed mice produced a remarkable amount of IL-10. The clones from casein-fed mice produced
considerable amounts of TGF-β, while those from control mice produced only small amounts. The possible role of CD8+ T cells in oral tolerance is discussed.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
18.
Yuan-Zuo Li Yen-Peng Ho Shui-Tein Chen Tzyy-Wen Chiou Zong-Sian Li David Shiuan 《Biochemistry. Biokhimii?a》2009,74(2):215-220
Mycoplasma hyopneumoniae is an important pathogen of pigs causing enzootic pneumonia of swine. The pathogen remains largely enigmatic as far as the
host-pathogen interactions are concerned. In the present study, the protein profiles of two strains of M. hyopneumoniae were compared by two-dimensional gel electrophoresis and mass spectrometry. The results indicate that the major adhesin P97,
the 50-kDa protein derived from P159 adhesin, and the 43-kDa cleavage product of P102 are expressed at much higher levels
in the pathogenic strain 232. In contrast, the avirulent strain J switches its focus to metabolism and expresses more glyceraldehyde
3-phosphate dehydrogenase in gluconeogenesis and lactate dehydrogenase, pyruvate dehydrogenase, and phosphate acetyltransferase
in the pyruvate metabolism pathway. We speculate that the avirulent strain may have developed better capabilities to cope
with the rich environment during repeated inoculations. Simultaneously, the capability to infect host cells may become less
important so that the adhesion-related protein genes are down-regulated.
Published in Russian in Biokhimiya, 2009, Vol. 74, No. 2, pp. 264–271. 相似文献
19.
S. Bhattacharyya S. N. Das A. B. Dey K. Nagarkar J. Lobo S. K. Kapoor H. K. Prasad 《Journal of biosciences》1997,22(1):99-109
Interferon-(IFN-γ) has been considered to be a critical protective immunomodulatory component against
Mycobacterium tuberculosis (M. tb.) infection. In this study T-cell proliferation and IFN-γ production upon stimulation with M. tb. were assessed in
patients of pulmonary tuberculosis and healthy contacts. The studies were based on lymphocyte transformation test and detection
of intracellular IFN-γ production by CD4 + ve T-cells by flowcytometry. Patients showed lower levels of proliferation, the
stimulation index being in the range of 2.17 1.1 (mean + SD) compared to the contacts (SI = 4 59±1.6) (P < 0.01). The kinetics
of intracellular induction of IFN-γ on M. tb. stimulation showed a proportional increase in the CD4 + ve T-cell population.
The increase was maximal between 96–120 h of culture. In healthy contacts the number of IFN-γ expressing CD + ve T-cells increased
to 2.5 to 41 × 104 cells/ml in M. tb. stimulated cultures compared to control cultures (0.1 – 15 × 104). In contrast patients showed no/marginal increase in CD4 + ve T-cell population expressing intracellular IFN-γ Thus the
lack of induction of IFN in CD4 + ve T-cells in patients could be a critical shortcoming in their ability to combat tubercle
bacilli infection. 相似文献
20.
Mora-Montes HM López-Romero E Zinker S Ponce-Noyola P Flores-Carreón A 《Antonie van Leeuwenhoek》2008,93(1-2):61-69
Previous studies demonstrated the presence in Candida albicans ATCC 26555 of two soluble α1,2-mannosidases: E-I and E-II. In contrast, in the C. albicans CAI-4 mutant only E-I was detected and it could be processed by a membrane-bound proteolytic activity from the ATCC 26555
strain, generating an active 43 kDa polypeptide. Here, α1,2-mannosidase E-I from strain ATCC 26555 was purified by conventional
methods of protein isolation and affinity chromatography in Concanavalin A-Sepharose 4B. Analytical electrophoresis of the
purified enzyme revealed two polypeptides of 52 and 23 kDa, the former being responsible for enzyme activity as revealed by
zymogram analysis. Time course proteolysis with an aspartyl protease from Aspergillus saitoi, converted α1,2-mannosidase E-I into an active polypeptide of 43 kDa which trimmed Man9GlcNAc2, generating Man8GlcNAc2 isomer B and mannose. Trimming was inhibited preferentially by 1-deoxymannojirimycin. Both, the molecular mass and the enzyme
properties of the proteolytic product were identical to those described for α1,2-mannosidase E-II therefore supporting the
notion that E-I is the precursor of E-II. 相似文献