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641.
Generation of natural killer cells from both Fc gamma RII/III+ and Fc gamma RII/III- murine fetal liver progenitors 总被引:3,自引:0,他引:3
In vitro culture of day-15.5 murine fetal liver (FL) cells in the presence of recombinant interleukin-2 (IL-2) results in the expansion of Fc gamma RII/III+ CD3-Ti-NK1.1+ cells displaying both natural killer (NK) and antibody-dependent cell cytotoxicity (ADCC) cytolytic activities. These FL-derived NK cells express Fc gamma RIII (CD16) in association with an Fc epsilon RI gamma homodimer on their surface. In contrast, in vitro expansion of FL cells in the absence of IL-2 generates noncytotoxic cells belonging to the myelomonocytic lineage (Mac1+Gr1+NK1.1-). Hence, IL-2 appears to be critical for the proliferation and differentiation of NK cells from FL progenitors. Experiments in which FL cells were fractionated by density gradient centrifugation before in vitro expansion showed that NK progenitors are contained within a cell population with a density of 1.04 < d < 1.08 g/mL. Cells with d > 1.08 g/mL (representing > or = 40% of FL cells) have no such NK progenitor activity. In addition, after intrathymic injection into Ly5 congenic host animals, day-15.5 CD4-CD8- FL cells mature into CD4+CD8+ thymocytes within 12 days. Interestingly, this T- cell progenitor activity is restricted to subpopulations of FL cells that also contain NK progenitors, but is absent in high-density (d > 1.08 g/mL) FL cells. Finally, fractionation of FL cells according to surface expression of Fc gamma RII/III complexes shows that NK (and T- lymphocyte) progenitors are found in both Fc gamma RII/III+ and Fc gamma RII/III-FL subpopulations. 相似文献
642.
R. M. Talaat A. M. Elmaghraby S. S. Barakat M. EL‐Shahat 《Clinical and experimental immunology》2014,176(2):291-300
Immune thrombocytopenic purpura (ITP) is acquired autoimmune disease in children characterized by the breakdown of immune tolerance. This work is designed to explore the contribution of different lymphocyte subsets in acute and chronic ITP children. Imbalance in the T helper type 1 (Th1)/Th2 cytokine secretion profile was investigated. The frequency of T (CD3+, CD4+, CD8+) and B (CD19+) lymphocytes, natural killer (NK) (CD16+56+) and regulatory T (Treg) [CD4+CD25+highforkhead box protein 3 (FoxP3)+] cells was investigated by flow cytometry in 35 ITP children (15 acute and 20 chronic) and 10 healthy controls. Plasma levels of Th1 cytokines [interferon (IFN-γ) and tumour necrosis factor (TNF-α)] and Th2 [interleukin (IL)-4, IL-6 and IL-10)] cytokines were measured using enzyme-linked immunosorbent assay (ELISA). The percentage of Treg (P < 0·001) and natural killer (NK) (P < 0·001) cells were significantly decreased in ITP patients compared to healthy controls. A negative correlation was reported between the percentage of Treg cells and development of acute (r = −0·737; P < 0·01) and chronic (r = −0·515; P < 0·01) disease. All evaluated cytokines (IFN-γ, TNF-α, IL-4, IL-6 and IL-10) were elevated significantly in ITP patients (P < 0·001, P < 0·05, P < 0·05, P < 0·05 and P < 0·001, respectively) compared to controls. In conclusion, our data shed some light on the fundamental role of immune cells and their related cytokines in ITP patients. The loss of tolerance in ITP may contribute to the dysfunction of Tregs. Understanding the role of T cell subsets will permit a better control of autoimmunity through manipulation of their cytokine network. 相似文献
643.
Mohamed A. EL-Malky Saeed A. Al-Harthi Raafat T. Mohamed Mohamed A. EL Bali Niveen S. Saudy 《Parasitology research》2014,113(6):2277-2284
Toxoplasma gondii (T. gondii) is one of the most successful intracellular protozoan parasites on earth and highly prevalent in most warm-blooded vertebrates. There are no drugs that target the chronic cyst stage of this infection; therefore, development of an effective vaccine would be an important advance in disease control. Oligodeoxynucleotides (ODN) which contain immunostimulatory CG motifs (CpG ODN) can promote T-helper 1 (Th1) responses, an adjuvant activity that is desirable for vaccination against intracellular pathogen. In this study, we compare the immune responses of Toxoplasma susceptible C57BL/6 mice following intranasal and intramuscular vaccination with Toxoplasma lysate antigen (TLA) with or without CpG ODN as adjuvant. Immunized and control non-immunized mice were challenged with 85 cyst of the moderately virulent Beverley strain of T. gondii. Intranasal vaccination gave significantly a higher protection compared to other groups as indicated by prolonged survival and significantly reduced brain cyst burden (P?<?0.01). Intranasal vaccination stimulated cellular immunity towards Th1 response characterized by significant INF-γ production (P?<?0.01). Furthermore, fecal IgA antibody levels as an indicator of mucosal immune responses were significantly higher (P?<?0.05) in intranasal vaccinated group before the challenge compared to all other groups. Intranasal vaccination was not able to upgrade the Th1 humoral arm. In contrast, intramuscular vaccination enhanced humoral immunity towards a type Th1 pattern characterized by a significant increase of specific IgG and Ig2a. Our results suggest that intranasal administration of CpG/TLA would provide a stable, pronounced, and effective vaccine against toxoplasmosis through stimulation of Th1 cellular immunity and mucosal IgA. 相似文献
644.
EL Koster JS Dashe DD McIntire RM Ramus 《The journal of maternal-fetal & neonatal medicine》2013,26(1):3-7
Objective: To evaluate the relationship between maternal serum α-fetoprotein (MSAFP) and the risk of persistent placenta previa.Methods: We conducted a retrospective cohort study of singleton pregnancies with sonographic evidence of placenta previa at 15?–?20 weeks' gestation, between October 1991 and August 2000. Only pregnancies with MSAFP determination at 15?–?20 weeks' gestation and non-anomalous live-born infants ??24 weeks' gestation were included. Pregnancies in which Cesarean delivery was performed for placenta previa were considered persistent; this was the primary outcome.Results: Of 275 women with previa at 15?–?20 weeks' gestation, 33 (12%) had previa at delivery. Trend analysis revealed a greater likelihood of persistent previa with increasing MSAFP values (p?=?0.01). Mid-trimester MSAFP <?1 multiple of the median (MoM) was associated with a decreased incidence of persistence of 4%, significantly less than the risk at ??1 MoM (16%; p?=?0.01).Conclusions: There is an association between increasing MSAFP values and greater likelihood of persistent placenta previa. An MSAFP value <?1 MoM is associated with a reduction in the risk of persistence of previa to delivery. 相似文献
645.
Expression of TNF and the 55-kDa TNF receptor in epidermis, oral mucosa, lichen planus and squamous cell carcinoma 总被引:2,自引:0,他引:2
TNF has diverse biological effects including a role in the immune response and growth regulatory effects.
OBJECTIVES: The aim of this study was to determine the nature and location of cells able to synthesise and respond to TNF in oral mucosa in health and disease.
MATERIALS AND METHODS: The location of immuno-reactive TNF and 55-kDa and 7s-kDa TNF receptors was demonstrated using immunohistology. We also used RT-PCR to help determine the sites of synthesis of this cyto-kine in oral mucosa.
RESULTS: Only occasional TNF-positive cells were detected in normal epidermis and oral mucosa. However, this cytokine was found throughout the epithelia in oral lichen planus, leukoplakia and squamous cell carcinoma (SCC). The possible cellular sources and biological effects of TNF in these disease processes is discussed. The 55-kDa TNFR was expressed at the cell membrane throughout the epidermis, but confined to the lower cell layers on oral mucosa. Ten of 22 SCC did not express this receptor. A significant correlation was observed between the velocity of tumour growth and absence of TNF receptors.
CONCLUSIONS: The growth inhibitory and immuno-regulatory effects of TNF may be modulated by changes in receptor expression and alterations in synthesis of this cytokine in a subgroup of oral SCC. 相似文献
OBJECTIVES: The aim of this study was to determine the nature and location of cells able to synthesise and respond to TNF in oral mucosa in health and disease.
MATERIALS AND METHODS: The location of immuno-reactive TNF and 55-kDa and 7s-kDa TNF receptors was demonstrated using immunohistology. We also used RT-PCR to help determine the sites of synthesis of this cyto-kine in oral mucosa.
RESULTS: Only occasional TNF-positive cells were detected in normal epidermis and oral mucosa. However, this cytokine was found throughout the epithelia in oral lichen planus, leukoplakia and squamous cell carcinoma (SCC). The possible cellular sources and biological effects of TNF in these disease processes is discussed. The 55-kDa TNFR was expressed at the cell membrane throughout the epidermis, but confined to the lower cell layers on oral mucosa. Ten of 22 SCC did not express this receptor. A significant correlation was observed between the velocity of tumour growth and absence of TNF receptors.
CONCLUSIONS: The growth inhibitory and immuno-regulatory effects of TNF may be modulated by changes in receptor expression and alterations in synthesis of this cytokine in a subgroup of oral SCC. 相似文献
646.
647.
Mohammed Al-Biltagi Osama A. Tolba Maher Ahmed Abd ElHafez Ahmed Abd ElBasset Abo-Elezz Eman Kamel EL Kady Sahar Mohey El-din Hazza 《Pediatric nephrology (Berlin, Germany)》2016,31(8):1329-1339
Objective
The objective of this study was to evaluate cardiac function in children with end-stage renal disease (ESRD) on regular hemodialysis using speckle tracking echocardiography (STE) and correlate results with plasma glutathione level as a marker of oxidative stress.Methods
The study involved 30 children with ESRD and 30 healthy controls. The plasma glutathione and C-reactive protein (CRP) levels were measured, and cardiac function was evaluated using conventional echocardiography and STE.Results
Plasma glutathione levels were significantly lower and CRP significantly higher in patients than in controls. Children with ESRD had significant systolic and diastolic cardiac dysfunctions detected by STE compared with controls. Conventional echocardiography failed to detect these dysfunctions. There was significant increase in left-ventricular relative wall thickness (LV-RWT) in patients, especially those with hypertension, compared with the control group. There was also significant impairment of LV and right-ventricular (RV) global longitudinal strain (GLS) and torsion; however, LV-GLS was significantly better in hypertensive than in normotensive patients. The degree of impairment in GLS and cardiac torsion negatively correlated with plasma glutathione levels.Conclusion
Significant oxidative stress was present in children with ESRD and was correlated with the degree of cardiac dysfunction detected early using the new cardiac imaging modality, STE.648.
THE AETIOLOGY OF IMPETIGO CONTAGIOSA 总被引:1,自引:0,他引:1
The study egtailed bacteriological investigation of 131 cases of impetigo contagiosa, including the isolation and identification of the offending organisms. The data showed the presence of Staphylococcus aureus in pure culture in 40.5% of the cases, and in mixed growth with betahaemolytic streptococci and other organisms in 47% of the cases. Streptococci came next in frequency and were isolated in pure culture from 9.1% of cases, and in combination with other organisms in 36.7% of the cases. A haemolytic diphtheroid having the characteristics of Corynebacterium pyogenes was isolated in pure culture from one case and in mixed growth in 5.3% of the cases. 相似文献
649.
Amal Akammar Sylvie Kolani Zineb Benchekroune Nizar EL Bouardi Meriem Haloua Moulay Youssef Alaoui Lamrani Meryem Boubbou Mounia Serraj Mohamed Smahi Maaroufi Maroufi Badreeddine Alami 《Radiology Case Reports》2021,16(9):2570
Thymolipoma is a rare benign neoplasm of the thymus containing both mature adipose tissue and thymic tissue. We report a case of a 34‐year‐οld man, presenting a mass of the anterior mediastinum, the radiology investigation and operatory piece diagnosed a thymolipoma.This study highlights the clinical diagnostic and therapeutic features as well as the evolutionary characteristics of this entity. 相似文献
650.
Noha Hosam EL Din Behairy Tarek Ahmed Rafaat Amr Salah EL Din El Nayal Magdy Ibrahim Bassiouny 《The Egyptian Journal of Radiology and Nuclear Medicine》2014