The role of third complement component (C3) in homing of hematopoietic stem/progenitor cells into bone marrow.
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Publications and source records attributed to Jun Yan.
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Several organs including hematopoietic ones may regenerate by attracting stem cells that are mobilized from their niches in response to stress related to tissue/organ damage and after mobilization circulate in the peripheral blood. The trafficking of these cells is regulated by alpha-chemokine stromal derived factor-1 (SDF-1) that is upregulated in damaged organs and binds to seven-transmembrane-span G-protein-coupled CXCR4 receptor that is expressed on circulating stem cells. In parallel, evidence has accumulated that the complement (C) system, which is part of innate immunity, may also orchestrate regeneration. C becomes activated with the release of the third complement component (C3) cleavage fragments (e.g., C3a, desArgC3a, and iC3b) during tissue/organ injury. Our recent work demonstrated that these fragments modulate responsiveness of CXCR4+ stem cells to an SDF-1 gradient. Thus the high concentration of both SDF-1 and C3 cleavage fragments in damaged organs results in the formation of an optimal gradient for chemoattracting circulating CXCR4+ stem cells. In this review we will focus on interactions between the SDF-1-CXCR4 axis and the C3 cleavage fragments in a model of mobilization, trafficking, and homing of hematopoietic stem/progenitor cells (HSPC).
Two novel facultatively anaerobic bacterial strains, BL-34(T) and BL-35, isolated from groundwater contaminated by a mixture of chlorosolvents were characterized using a polyphasic approach. The two strains exhibited essentially identical taxonomic features except for a vitamin B(12) requirement by strain BL-35 for optimal growth. Phylogenetically, the isolates were affiliated with members of the family Propionibacteriaceae and were placed in a phylogenetic branch adjacent to, but distinct from, those of the genera Propionimicrobium, Propionibacterium, Luteococcus, Propioniferax and Tessaracoccus. The cells of the novel strains were Gram-positive, non-motile, non-spore-forming pleomorphic rods. They produced catalase but not oxidase, and nitrate reduction did not occur in peptone/yeast extract/glucose medium. Propionate and acetate were the predominant products of glucose fermentation. Fermentation occurred in the presence of 1,2-dichloroethane and 1,1,2-trichloroethane at concentrations up to at least 9.8 mM. The genomic DNA G+C content was 67.5-67.9 mol%. Menaquinone MK-9(H(4)) was the predominant respiratory quinone and meso-diaminopimelic acid was present in the cell-wall peptidoglycan layer. The major cellular fatty acids were C(15 : 0) and anteiso-C(15 : 0). On the basis of the results obtained in this study, strains BL-34(T) and BL-35 should be classified within a novel taxon, for which the name Brooklawnia cerclae gen. nov., sp. nov. is proposed. The type strain of Brooklawnia cerclae is BL-34(T) (=LMG 23248(T)=NRRL B-41418(T)). An additional strain, BL-35 (=LMG 23249=NRRL B-41419), was also characterized.
Steroid receptor coactivator-3 (SRC-3, also known as NCoA3, AIB1, p/CIP, RAC3, ACTR, and TRAM1), localized on a frequently amplified region, 20q12, has been associated with multiple cancers, including breast, gastric and prostate cancers. Although SRC-3 has been implicated as an oncogene, compelling evidence has only recently emerged implicating it as a causal factor in the genesis of human cancers. Here, we summarize recent evidence that indicates aberrant SRC-3 expression is important in hormone-sensitive and -insensitive human cancers.
BACKGROUND: Genital warts are a common sexually transmitted disease caused by human papillomaviruses. Podophyllotoxin 0.5%, approved for patient self-administration, has been used most extensively in the treatment of genital warts. Imiquimod, a novel immune response modifier capable of inducing interferon-alpha and a variety of cytokines, has been examined as a potential treatment for genital warts. But 0.5% podophyllotoxin and 5% imiquimod have not been compared in any extensive and formal studies, although they are the common topical agents for genital warts. OBJECTIVE: To evaluate the efficacy and safety of topical 5% imiquimod and 0.5% podophyllotoxin in the treatment of genital warts. METHODS: We searched Medline (1966 to June 2005), Embase (1974 to June 2005) and the Cochrane Controlled Trials Register (issue 3, 2005). Randomized controlled trials of 5% imiquimod or 0.5% podophyllotoxin in the treatment of genital warts were collected. Two reviewers extracted the data and independently assessed the quality of the included medical literature. Then, meta-analysis was conducted. RESULTS: Twelve studies including 3 placebo-controlled trials of imiquimod and 9 placebo-controlled trials of podophyllotoxin were included. The clinical cure rates of imiquimod and podophyllotoxin were 50.34 and 56.41%, respectively, without statistically significant differences between the two (p > 0.05). A combined analysis of the 3 studies on imiquimod showed a statistically significant difference to the placebo group [pooled odds ratio (OR) 11.65, 95% confidence interval (CI) 6.05-22.44], as did a combined analysis of the 9 studies on podophyllotoxin (pooled OR 16.70, 95% CI 7.06-39.48). The most common adverse events of imiquimod were erythema, erosion, excoriation, itching and burning; those of podophyllotoxin were burning, pain, erosion, itching and inflammation. CONCLUSION: Imiquimod and podophyllotoxin possess similar curative effects on condylomata acuminata but podophyllotoxin has more serious adverse effects.
OBJECTIVE: To investigate the effect of cholecystokinin octapeptide (CCK-8) on lipopolysaccharide (LPS)-elicited inducible nitric oxide synthase (iNOS) expression in vascular endothelial cells. METHODS: Human umbilical vein endothelial cell line (ECV-304 cells) was stimulated with vehicle (normal saline) or LPS in the presence (0.01, 0.1, 1 mg/L) or absence (0.1 mg/L) of CCK-8 (10(-6)-10(-8)mol/L). Nitric oxide (NO) level and cellular nitric oxide synthase (NOS) activity were determined with spectrophotometrically. The iNOS expression was detected with immunocytochemical technique and Western blot. RESULTS: Compared with normal saline, LPS significantly induced the upregulation of iNOS protein expression in the cultured ECV-304 cells, and NOS activity in ECV-304 cells and NO level in cultured media were increased. CCK-8 obviously inhibited above-mentioned effect of LPS in a dose-dependent manner. Whereas CCK-8 alone did not showed effect on iNOS protein expression, NO level and cellular NOS activity as compared with those values when vehicle was used. CONCLUSION: CCK-8 inhibited LPS-elicited iNOS expression and NO production in ECV-304 cells.
Using the Genetic Analysis Workshop 14 simulated datasets we carried out nonparametric linkage analyses and applied a log-linear method for analysis of case-parent-triad data with stratification on parental mating type. We proposed and applied a random effect modelling approach to explore the impact of population heterogeneity on tests of association between genetic markers and disease status. The estimated genetic effect may appear to be strongly significant in one population but nonsignificant in another population, leading to confusion about interpretation. However, when results are interpreted in the light of a random effects model, both studies may be making similar statements about a genetic effect that varies depending on environment and background.
A novel strain, designated as BL-10(T), was characterized using a polyphasic approach after isolation from groundwater contaminated by a mixture of chlorosolvents that included 1,1,2-trichloroethane, 1,2-dichloroethane, and vinyl chloride. Stain BL-10(T) is a facultatively anaerobic bacterium able to ferment glucose to form propionate, acetate, formate, lactate, and succinate. Fermentation occurred in the presence of 1,2-dichloroethane and 1,1,2-trichloroethane at concentrations to at least 9.8 and 5.9 mM, respectively. Cells are Gram-positive, rod-shaped, non-motile, and do not form spores. Oxidase and catalase are not produced and nitrate reduction did not occur in PYG medium. Menaquinone MK-9 is the predominant respiratory quinone and meso-diaminopimelic acid is present in the cell wall peptidoglycan layer. Major cellular fatty acids are C(15:0), iso C(16:0), and anteiso C(15:0). Genomic DNA G + C content is 69.9 mol%. Phylogenetic analysis based on 16S rRNA gene sequence comparisons showed strain BL-10(T) to fall within the radiation of genera Propionicimonas and Micropruina. On the basis of the results obtained in this study, it is proposed that strain BL-10(T) should be classified as a novel taxon, for which the name Propionicicella superfundia gen. nov., sp. nov. is proposed. The type strain of Propionicicella superfundia is BL-10(T) (=ATCC BAA-1218(T), =LMG 23096(T)).
Muscarinic acetylcholine receptors are extensively involved in cortical cognition and learning-induced or experience-dependent cortical plasticity. The most abundant muscarinic receptor subtype in the cerebral cortex is the M1 receptor, but little is known about its contribution to experience-dependent plasticity of the adult auditory cortex. We have examined the role of the M1 receptor in experience-dependent plasticity of the auditory cortex in mice lacking the M1 (chrm1) gene. We show here that electrical stimulation of the basal forebrain, a major source of cortical cholinergic inputs, facilitated the auditory responses of cortical neurons in both wild types and M1 mutants. The basal forebrain stimulation alone caused change in the best frequencies of cortical neurons that were significantly greater in M1 mutants. When animals received the paired stimuli of electrical stimulation of the basal forebrain and tone, the frequency tuning of cortical neurons systematically shifted toward the frequency of the paired tone in both wild types and M1 mutants. However, the shift range in M1 mutants was much smaller than that in wild-type mice. Our data suggest that the M1 receptor is important for the experience-dependent plasticity of the auditory cortex.
D-type cyclins are essential for the progression through the G1 phase of the cell cycle. Besides serving as cell cycle regulators, D-type cyclins were recently reported to have transcription regulation functions. Here, we report that cyclin D3 is a new interacting partner of vitamin D receptor (VDR), a member of the superfamily of nuclear receptors for steroid hormones, thyroid hormone, and the fat-soluble vitamins A and D. The interaction was confirmed with methods of yeast two-hybrid system, in vitro binding analysis and in vivo co-immunoprecipitation. Cyclin D3 interacted with VDR in a ligand-independent manner, but treatment of the ligand, 1,25-dihydroxyvitamin D3, strengthened the interaction. Confocal microscopy analysis showed that ligand-activated VDR led to an accumulation of cyclin D3 in the nuclear region. Cyclin D3 up-regulated transcriptional activity of VDR and this effect was counteracted by overexpression of CDK4 and CDK6. These findings provide us a new clue to understand the transcription regulation functions of D-type cyclins.
Myelotoxic injury in the bone marrow (BM) as a consequence of total body irradiation (TBI) or granulocyte colony-stimulating factor (G-CSF) mobilization results in the deposition of iC3b on BM stroma (stroma-iC3b). In the present study, we have examined how stroma-iC3b interacts with hematopoietic progenitor cells (HPCs) and the role of complement (C) and complement receptor 3 (CR3) in BM injury/repair. We demonstrate here that stroma-iC3b tethers HPCs via the inserted (I) domain of HPC complement receptor 3 (CR3, CD11b/CD18, Mac-1). Following irradiation, stroma-iC3b was observed in the presence of purified IgM and normal mouse serum (NMS), but not serum from Rag-2(-/-) mice, implicating a role for antibody (Ab) and the classic pathway of C activation. Furthermore, a novel role for soluble yeast beta-glucan, a ligand for the CR3 lectin-like domain (LLD), in the priming of CR3(+) HPC is suggested. Soluble yeast beta-glucan could enhance the proliferation of tethered HPCs, promote leukocyte recovery following sublethal irradiation, and increase the survival of lethally irradiated animals following allogeneic HPC transplantation in a CR3-dependent manner. Taken together, these observations suggest a novel role for C, CR3, and beta-glucan in the restoration of hematopoiesis following injury.
Prostate cancer is the most common cancer in men in America. Currently, steroid receptor coactivators have been proposed to mediate the development and progression of prostate cancer, at times in a steroid-independent manner. Steroid receptor coactivator-3 (SRC-3, p/CIP, AIB1, ACTR, RAC3, and TRAM-1) is a member of the p160 family of coactivators for nuclear hormone receptors including the androgen receptor. SRC-3 is frequently amplified or overexpressed in a number of cancers. However, the role of SRC-3 in cancer cell proliferation and survival is still poorly understood. In this study, we show that SRC-3 is overexpressed in prostate cancer patients and its overexpression correlates with prostate cancer proliferation and is inversely correlated with apoptosis. Consistent with patient data, we have observed that reduction of SRC-3 expression by small interfering RNA decreases proliferation, delays the G1-S transition, and increases cell apoptosis of different prostate cancer cell lines. Furthermore, with decreased SRC-3 expression, proliferating cell nuclear antigen and Bcl-2 expression, as well as bromodeoxyuridine incorporation in prostate cancer cells are reduced. Finally, knockdown of SRC-3 with inducible short hairpin RNA expression in prostate cancer cells decreased tumor growth in nude mice. Taken together, these findings indicate that SRC-3 is an important regulator of prostate cancer proliferation and survival.
OBJECTIVE: To detect the antitumor activity of Shuang-Xi-Zuo-Wan-1(Eb), a novel organoselenium compound, in C57/BL mice transplanted with Lewis lung cancer(LLC). METHODS: The LLC transplanted C57/BL mice model was established,and the mice were randomly divided into four groups, including high dose Eb group (25.0 mg/kg), low dose Eb group (12.5 mg/kg), positive control group (DDP, 2.0 mg/kg) and negative control group (solvent). Each group had twelve mice. Intraperitoneal injections (ip.) of four pharmaceuticals were performed once a day through the abdominal wall separately, from the second to the eighth days after cancer was transplanted. On the eleventh day, six mice of each group were killed and the influences of Eb on growth speed, size, weight, invasion, inhibitory rate, proliferation index and apoptosis rate of LLC were observed and calculated. The remaining mice were fed till all of them died naturally and the average survival time of each group was calculated. RESULTS: Eb could inhibit the growth and infiltration of LLC (the cancer inhibitory rate of high does Eb was 80.31%) obviously and prolong the average survival time of these with mice cancer. After being given Eb, the nuclear of the cancer cell concentrated and the fission phase cells reduced. In addition,the number of apoptosis cancer cells increased. CONCLUSION: The novel organoselenium compound Eb has antitumor activity in vivo. It can inhibit the growth and infiltration of LLC in mice, and induce the apoptosis of cancer cells.
Human thioredoxin reductase (TrxR) system is associated with cancer cell growth and anti-apoptosis process. Effects of 1, 2-[bis (1,2-Benzisoselenazolone-3 (2H) -ketone)]ethane (BBSKE), a novel TrxR inhibitor, were investigated on A549, HeLa, Bel-7402, BGC823 and KB cell lines. After treated with BBSKE, a good linear correlation coefficient (r>or=0.989) between TrxR activity and cell viability exists in each cell line together with cell growth/proliferation inhibition and apoptosis through Bcl-2/Bax and Caspase-3 pathways. These results suggest that there exists some relationship between TrxR inactivation and growth/proliferation inhibition or apoptosis in the investigated cell lines.
CD19 is a B cell-surface molecule that participates as an important regulatory signaling complex for antigen bound at the surface by Ig. Triggering of CD19 through its linkage with CD21 amplifies signals transduced through the Src family kinases and modulates B cell differentiation in response to antigen. This study examines the kinetics of antigen uptake and processing of antigen directly targeted to the CD19 protein on purified B cells. We have demonstrated that the antigen internalized within minutes through CD19 forms a cap at the B cell surface and can be found within lysosomes in the cytoplasm in 90 min. B cells acquiring antigen via CD19 express elevated levels of B7-1 and B7-2 co-stimulatory molecules. Moreover, antigen-anti-CD19 complexes administered intravenously bind B cells in vivo and activate antigen-specific T cells more efficiently than non-specific uptake and in a manner similar to antigen taken up through surface IgM on B cells. This work illustrates an important and previously unrecognized mechanism for targeting proteins to B lymphocytes for antigen presentation and activation of CD4 T cells.
Intravenous and orally administered beta-glucans promote tumor regression and survival by priming granulocyte and macrophage C receptor 3 (CR3, iC3bR and CD11b/CD18) to trigger the cytotoxicity of tumor cells opsonized with iC3b via anti-tumor Abs. Despite evidence for priming of macrophage CR3 by oral beta-glucan in vivo, the current study in C57BL/6 and BALB/c mice showed that granulocytes were the essential killer cells in mAb- and oral beta-glucan-mediated tumor regression, because responses were absent in granulocyte-depleted mice. Among granulocytes, neutrophils were the major effector cells, because tumor regression did not occur when C5a-dependent chemotaxis was blocked with a C5aR antagonist, whereas tumor regression was normal in C3aR(-/-) mice. Neutrophil recruitment by C5a in vivo required amplification via leukotriene B(4), because both C5a-mediated leukocyte recruitment into the peritoneal cavity and tumor regression were suppressed in leukotriene B(4)R-deficient (BLT-1(-/-)) mice.
Atrial natriuretic peptide (ANP) is a vasodilator peptide primarily produced in the heart. Locally synthesized ANP has been found in reproductive tissues of various mammals and humans, and plays an important role in rat oocyte maturation and human sperm function. The objective of the present study was to determine the effects of ANP on the function (acrosome reaction and zona penetration) of giant panda spermatozoa. In fresh and frozen-thawed spermatozoa that had been preincubated for 2.5h, treatment with ANP (for 60 min) significantly increased the proportion of acrosome-reacted spermatozoa; maximal response (an acrosome reaction in 18.3 and 21.8% of fresh and frozen-thawed spermatozoa, respectively) was detected at 1 nM ANP. Treatment with C-ANP-(4-23), an analogue of ANP and specific binder to natriuretic peptide receptors-C (NPRC), had no significant effect on the acrosome reaction. However, the cyclic guanosine 5'-monophosphate (cGMP)-dependent protein kinase (PKG) inhibitor KT5823 completely abolished the effect of ANP on acrosome reaction. The effects of ANP, caffeine and heparin on frozen-thawed sperm function were studied by insemination of porcine salt-stored oocytes in a modified Tris-buffered medium (mTBM). The presence of ANP, caffeine or heparin in the insemination medium resulted in a higher proportion (P < 0.05) of oocytes with spermatozoa in the zona and perivitelline space (PVS), and a higher average number of spermatozoa/oocyte (P < 0.05) in the zona and PVS. However, in the absence of ANP, caffeine and heparin, there were no oocytes with a spermatozoon in the PVS. There were no differences among ANP, caffeine or heparin treatments for the proportion of oocytes penetrated or average number of spermatozoa/oocyte in the zona and PVS. In conclusion, we inferred that ANP induced the acrosome reaction of preincubated giant panda spermatozoa by a PKG pathway. Furthermore, ANP enhanced the penetrability of porcine salt-stored oocytes by frozen-thawed giant panda spermatozoa.
During the period 1997-2000 a technical assistance project to build capacity for community-based health promotion was implemented in seven cities and one province in China. The technical assistance project formed part of a much larger World Bank supported program to improve disease prevention capabilities in China, commonly known as Health VII. The technical assistance project was funded by the Australian Agency for International Development. It was designed to develop capacity within the Ministry of Health (MOH) and the cities and province in the management of community-based health promotion projects, as well as supporting institutional development and public health policy reform. There are some relatively unique features of this technical assistance which helped shape its implementation and impact. It sought to provide the Chinese MOH and the cities and province with an introduction to comprehensive health promotion strategies, in contrast to the more limited information, education and communication strategies. The project was provided on a continuing basis over 3 years through a single institution, rather than as a series of ad hoc consultancies by individuals. Teaching and learning processes were developmental, leading progressively to a greater degree of local Chinese input and management to ensure sustainability and maintenance of technical support for the project. Based on this experience, this paper presents a model for capacity building projects of this type. It describes the education, training and planning activities that were the key inputs to the project, as well as the limited available evidence on the impact of the project. It describes how the project evolved over time to meet the changing needs of the participants, specifically how the content of the project shifted from a risk-factor orientation to a settings-based focus, and the delivery of the project moved from an expert-led approach to a more participatory, problem based learning approach. In terms of impact, marked differences before and after the implementation of the training activities were identified in key areas for reform, in addition to the self reported positive change in knowledge, and a high level of participant satisfaction. Key lessons are summarized. Technical assistance projects of this kind benefit from continuity and a high level of coordination, the provision of culturally and linguistically appropriate teaching, and a clear understanding of the need to match workforce development with organizational/institutional development.