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991.

Background

Cytokine-induced killer (CIK) cells are typically differentiated in vitro with interferon (IFN)-γ and αCD3 monoclonal antibodies (mAb), followed by the repeated provision of interleukin (IL)-2. It is presently unknown whether thymoglobulin (TG), a preparation of polyclonal rabbit γ immunoglobulins directed against human thymocytes, can improve the generation efficiency of CIK cells compared with αCD3 mAb in a clinical-grade culture protocol.

Methods

Peripheral blood mononuclear cells (PBMC) from 10 healthy donors and 4 patients with solid cancer were primed with IFN-γ on day 0 and low (50 ng/ml), intermediate (250 ng/ml) and high (500 ng/ml) concentrations of either αCD3 mAb or TG on day 1, and were fed with IL-2 every 3 days for 21 days. Aliquots of cells were harvested weekly to monitor the expression of representative members of the killer-like immunoglobulin receptor (KIR), NK inhibitory receptor, NK activating receptor and NK triggering receptor families. We also quantified the frequency of bona fide regulatory T cells (Treg), a T-cell subset implicated in the down-regulation of anti-tumor immunity, and tested the in vitro cytotoxic activity of CIK cells against NK-sensitive, chronic myeloid leukaemia K562 cells.

Results

CIK cells expanded more vigorously in cultures supplemented with intermediate and high concentrations of TG compared with 50 ng/ml αCD3 mAb. TG-driven CIK cells expressed a constellation of NK activating/inhibitory receptors, such as CD158a and CD158b, NKp46, NKG2D and NKG2A/CD94, released high quantities of IL-12p40 and efficiently lysed K562 target cells. Of interest, the frequency of Treg cells was lower at any time-point compared with PBMC cultures nurtured with αCD3 mAb. Cancer patient-derived CIK cells were also expanded after priming with TG, but they expressed lower levels of the NKp46 triggering receptor and NKG2D activating receptor, thus manifesting a reduced ability to lyse K562 cells.

Conclusions

TG fosters the generation of functional CIK cells with no concomitant expansion of tumor-suppressive Treg cells. The culture conditions described herein should be applicable to cancer-bearing individuals, although the differentiation of fully functional CIK cells may be hindered in patients with advanced malignancies.  相似文献   
992.
993.
Grapevine yellow speckle viroid 1 (GYSVd-1), Grapevine yellow speckle viroid 2 (GYSVd-2), Australian grapevine viroid (AGVd), Hop stunt viroid (HSVd) and Citrus exocortis viroid (CEVd) are the five viroids known to infect naturally grapevines. We developed a multiplex RT-PCR (mRT-PCR) method for the simultaneous detection of these five viroids and the amplification of the cDNA fragment of a host-derived mRNA (actin mRNA) as an internal positive control. Specific primers for each targeted viroid were designed by taking into account the sequence variability within and between the viroid species and tested in silico. The method was validated by testing 57 grapevine samples from Iran and showed reliability and high sensitivity. The RT-PCR-negative samples were further assayed by Northern-blot hybridization. For this, a method was developed for the simultaneous detection of three different grapevine viroids on a single hybridization membrane. In this survey, HSVd, GYSVd-1, AGVd, and GYSVd-2 were detected in 100, 95, 93, and 65% of the samples tested, respectively, confirming the wide distribution of these viroids in Iran. CEVd was not detected in any of the samples collected. Based on these results, HSVd is proposed as a positive internal control for mRT-PCR in the areas where this viroid is widespread, so as to reduce the time and costs of DNase treatment, which is required when a host-derived internal control is used. The mRT-PCR method has the potential to be used routinely for large-scale surveys and certification programs.  相似文献   
994.
A 70-year-old woman was referred to the authors' unit following hospitalization for cardiac failure, high urinary free cortisol concentrations and severe hypokaliemia. A computed tomography scan of the abdomen showed an adrenal adenoma. The 24-hour urinary free cortisol values were high and plasma cortisol levels failed to suppress following 1 mg dexamethasone test. Aldosterone to plasma renin activity ratio was also pathologic, confirmed by saline load. She showed no symptoms of glucocorticoid excess. She was diagnosed with combined primary hyperaldosteronism and Cushing's syndrome. Cases of adrenal incidentalomas co-secreting cortisol and aldosterone are rare; they should be addressed in patients undergoing adrenal surgery for Conn's syndrome to avoid adrenal insufficiency after removal of the tumor.  相似文献   
995.
STUDY QUESTION: What is the potential physiopathological role of tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) in recurrent miscarriage (RM), characterized by at least three consecutive pregnancy losses. SUMMARY ANSWER: The levels of serum TRAIL immediately after miscarriage in RM patients are significantly elevated with respect to that in first-trimester normal pregnant women, and recombinant TRAIL inhibits the adhesion and migration of HTR8 trophoblastic cells in vitro. WHAT IS KNOWN ALREADY: Both TRAIL and its trans-membrane receptors (TRAIL-R1, TRAIL-R2, TRAIL-R3?and TRAIL-R4) have been documented in the placenta, but their physiopathological role is incompletely understood. STUDY DESIGN, SIZE, DURATION: The study populations consisted of RM patients (n = 80) and first-trimester normal pregnant women (n = 80). Blood samples were obtained within 24 h after abortion (RM) or at gestational 12-week (normal pregnant women). As additional controls, third-trimester normal pregnant women (n = 28) were examined before (within 72 h) and after (within 24 h) partum. PARTICIPANTS/MATERIALS, SETTING, METHODS: The concentrations of TRAIL were analysed in serum samples by ELISA. In parallel, the effect of soluble recombinant TRAIL (0.1-1000 ng/ml) was analysed on the survival of primary extravillus trophoblasts (EVTs) and on the survival, proliferation, adhesion and migration of trophoblastic HTR8 cells. MAIN RESULTS AND THE ROLE OF CHANCE: The circulating levels of TRAIL in RM women (median: 52.5 pg/ml; mean and SD: 55.5 ± 24.4 pg/ml) were significantly higher with respect to first-trimester normal pregnant women (median: 44.9 pg/ml; mean and SD: 47 ± 15.1 pg/ml) and third-trimester normal pregnant women, as assessed before (median: 45.1 pg/ml; mean and SD: 46 ± 12.4 pg/ml) and after partum (median: 35.4 pg/ml; mean and SD: 38 + 17.5 pg/ml). Both primary EVT and HTR8 cells expressed detectable levels of TRAIL death receptors, but exposure to soluble recombinant TRAIL did not induce cell death of trophoblastic cells. On the other hand, TRAIL dose-dependently inhibited the adhesion of HTR8 cells to decidual endothelial cells (DEC) as well as the migration of HTR8 in transwell assays using either fibronectin or DEC. LIMITATIONS, REASONS FOR CAUTION: Although this study suggests that TRAIL might have a pathogenic role in RM by inhibiting both the adhesion and migration capabilities of first trimester trophoblastic cells, there is a possibility that the elevated serum levels of TRAIL in RM are not cause but rather the result of RM. WIDER IMPLICATIONS OF THE FINDINGS: Our current findings together with data of other authors suggest that circulating TRAIL should be further analysed as a potential important biomarker in different physiopathological settings. STUDY FUNDING/COMPETING INTEREST(S): This study was funded by FIRB projects (RBAP11Z4Z9_002 to Giorgio Zauli and RBAP10447J_002 to Paola Secchiero). The authors have no competing interests to declare.  相似文献   
996.
The frequency and clinical relevance of late recurrences of testicular germ cells tumors (GCTs) has increased in the past few decades because of the improved survival of patients following the introduction, in the late 1970s, of cisplatin-based chemotherapy. The late recurrences of GCT may take extremely variable features and occur several years after the primary tumor, making the diagnosis a challenge for both clinicians and pathologists. This study reports a case of a testicular seminoma that relapsed 28 years after surgery as an undifferentiated GCT with a heterologous component of neuroendocrine carcinoma that was initially misdiagnosed as a metastasis of primary intestinal tumor.  相似文献   
997.
Increased plasma levels of several acute phase proteins, such as C-reactive protein (CRP), have been documented among different patients with chronic renal failure (CRF). The aim of the present study was to determine whether pentraxin-3 (PTX3) is a reliable marker of inflammation in CRF. Plasma samples and monocytes were taken from 43 patients before and after undergoing haemodialysis (HD), from 45 uraemic patients (UR) without HD treatment and from 25 healthy controls. Plasma and monocyte samples were analyzed by ELISA for levels of PTX3, tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta) and interleukin-6 (IL-6); all of these protein levels were higher in CRF patients with respect to the controls. After HD, plasma PTX3 and cytokine levels increased. Inter- and intra-individual variations in CRP were observed in HD patients, while PTX3 plasma levels were stable. Release of PTX3, TNF-alpha, IL-1beta and IL-6 by unstimulated monocytes from patients, before and after HD, was higher with respect to UR patients and controls. After lipopolysaccharide stimulation, all values were higher in patients before HD than those in UR patients, but lower when compared to those in the controls. In contrast, no changes were observed after HD. A significant correlation among plasma PTX3 versus fibrinogen, TNF-alpha and IL-1beta was observed in HD and UR patients. Collectively, these data suggest that PTX3 protein may represent an additional and stable marker of inflammation in CRF.  相似文献   
998.
999.

Background  

Despite numerous studies aimed at verifying the antitumor activity of nitric oxide-releasing nonsteroidal antiflammatory drugs (NO-NSAIDs), little is known about the molecular targets responsible for their antineoplastic properties. In the present study, we investigated the mechanisms underlying the cytotoxicity of NCX 4040, a novel NO-aspirin with promising antineoplastic action, in in vitro human colon cancer models.  相似文献   
1000.
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