Fms-like tyrosine kinase 3 receptor ligand (Flt3L)-based vaccination administered with an adenoviral vector prevents tumor growth of colorectal cancer in a BALB/c mouse model

Purpose

Colorectal cancer is the third most frequent cancer in industrial nations. Therapeutic strategies to treat metastatic disease and prevent recurrence are needed. Anti-tumor immunity can be induced by dendritic cells. Dendritic cells can be expanded by the fms-like tyrosine kinase 3 ligand (Flt3L) in vivo. The aim of this study was to develop an adenoviral-based immune-gene therapy of colorectal cancer with Flt3L in a BALB/c mouse model.

Methods

A new Flt3L-encoding adenoviral vector (pAdFlt3L) was administered in two approaches in a CT26 colon cancer model in female BALB/c mice. In the therapeutic approach, pAdFlt3L was injected into the tail vein or directly into subcutaneous CT26 colon carcinoma tumors in BALB/c mice. In the vaccination protocol, mice were vaccinated with CT26 cell lysate and pAdFlt3L subcutaneous prior to subcutaneous application of vital CT26 cells.

Results

Application of pAdFlt3L led to high levels of Flt3L in vitro and in vivo. Significant expansion of dendritic cells after application of pAdFlt3L in vivo was confirmed by the use of CD11c and CD11b surface markers in immunohistochemistry and flow cytometry (p = 0.019). In the therapeutic approach, neither intravenous nor intratumoral treatments with pAdFlt3L lead to regression of CT26 tumors. In the vaccination protocol, vaccination completely prevented tumor growth and resulted in superior survival compared to control mice (p < 0.001).

Conclusions

Our results demonstrate that immunostimulatory therapy with pAdFlt3L is effective to prevent tumor development through vaccination and may represent a therapeutic tool to prevent metastatic disease.     

The influence of lifestyle (smoking and body mass index) on wound healing and long-term recurrence rate in 534 primary pilonidal sinus patients

Purpose

With pilonidal sinus disease (PSD) incidence increasing, lifestyle issues have been suspected to be responsible to worsen the results of PSD surgery at the same time. The influence of smoking and body mass index (BMI) on long-term recurrence rate in primary PSD surgery has not been investigated yet.

Methods

A total of 534 patients (German military cohort) were analyzed, comparing the wound healing rates of non-smoker with smoker, as well as recurrence rates in either groups. Simultaneously, the impact of BMI on wound healing and recurrence was studied. Recurrence rate was determined by Kaplan–Meier calculation following up to 20 years after primary PSD surgery.

Results

Using primary open surgery, smokers’ and non-smokers’ recurrence rates did not differ statistically (p?=?0.83; log rank). Comparable rates occurred following the primary midline closure technique (p?=?0.14; log rank). A BMI of 25 and higher was not associated with adverse wound healing neither in the primary midline closure (p?=?0.14) nor in the primary open treatment group (p?=?0.3); nevertheless, a trend may be seen that a BMI of 25 and above could assist a favorable wound healing rate.

Conclusions

The lifestyle parameter smoking and body weight statistically do not complicate wound healing or long-term recurrence rates for the first 20 years following primary PSD surgery in this study. As the BMI of 25 and above may have a beneficial influence on wound healing in primary open and primary midline closure, this observation has to be investigated for the today’s surgical procedures of elective first choice-asymmetrical and flap procedures.     

硅酸钙、β-磷酸三钙和羟基磷灰石三相陶瓷复合物与骨细胞活性的体外鉴定

由于羟基磷灰石陶瓷与骨无机质的化学成份相似,所以10年来研究者对羟基磷灰石陶瓷在骨修复替换中的应用进行了深入的研究.羟基磷灰石因其高生物相容性和骨传导性已被广泛的应用,但羟基磷灰石的再吸收能力差.立童对由硅酸钙、β-磷酸三钙和羟基磷灰石组成的三相陶瓷复合物进行了研究.在三相陶瓷复合物环境下,采用不同比率硅酸钙、β-磷酸三钙和羟基磷灰石对骨髓夹源间充质干细胞进行体外研究.细胞在加入和没有加入成骨细胞的情况下培养28 d.采用碱性磷酸酶活性、碱性磷酸酶基因码转录和骨唾液蛋白Ⅱ表达评估成骨分化水平.成骨细胞和破骨细胞在陶瓷复合80%羟基磷灰石材料上完成预实验.将鼠颅盖骨成骨细胞与人单核细胞共同培养以分析其向破骨细胞分化的可能性.结果显示人骨髓间充质干细胞在陶瓷复合物材料上表现出快速黏附和高度增殖率,在所有实验材料上,成骨诱导的骨髓间充质干细胞碱性磷酸酶活性增加,碱性磷酸酶基因码转录和骨唾液酸蛋白Ⅱ的表达在3种材料上同样增加.扫描电镜和聚焦激光扫描显微镜结果证明在陶瓷复合80%羟基磷灰石材料上的人单核细胞向破骨样细胞分化.结果提示制各的三相陶瓷复合材料支持人骨髓间充质干细胞的黏附、增殖和成骨分化,以及人单核细胞与成骨细胞联合培养条件下破骨细胞形成.     

Proliferation as a requirement for in vitro chondrogenesis of human mesenchymal stem cells

During embryonic cartilage development, proliferation and differentiation are tightly linked with a transient cell cycle arrest observed during determination and before main extracellular matrix production. Aim of this study was to address whether these steps are imitated during in vitro differentiation of mesenchymal stem cells (MSCs) and are crucial for a proper chondrogenesis. Human MSCs were expanded in distinct media and subjected to pellet culture in chondrogenic medium. Cells were labeled with 5-iodo-2'-deoxyuridin (IdU) or treated with mitomycin C at various time points during culture. Apoptosis was detected by cleaved caspase 3. Proliferation rate of expanded MSCs at start of pellet culture showed a positive correlation with chondrogenesis according to DNA content, proteoglycan deposition, collagen type II content, and final pellet size. Evenly distributed IdU signals at day 1 diminished and became restricted primarily to the periphery by day 3. Between days 10 and 21, IdU-positive cells were detected throughout coinciding with collagen type II positivity. Little IdU incorporation occurred after day 21 and in areas of strong matrix deposition. DNA content decreased and apoptosis was detected up to day 14. Irreversible growth arrest by mitomycin C fully blocked chondrogenic differentiation and seemed to arrest differentiation at the stage reached at treatment. In conclusion, chondrogenesis involved a transient proliferation phase appearing simultaneously with start of collagen type II deposition and growth was crucial for proper chondrogenesis. Growth and differentiation steps, thus, seemed closely coordinated and resembled, with respect to proliferation, stages known from embryonic cartilage development. Stimulation of proliferation and prevention of early apoptosis are attractive goals to further improve MSC chondrogenesis.     

Activating PDGFRA mutations in inflammatory fibroid polyps occur in exons 12, 14 and 18 and are associated with tumour localization

Huss S, Wardelmann E, Goltz D, Binot E, Hartmann W, Merkelbach‐Bruse S, Büttner R & Schildhaus H‐U (2012) Histopathology  61, 59–68 Activating PDGFRA mutations in inflammatory fibroid polyps occur in exons 12, 14 and 18 and are associated with tumour localization Aims: Inflammatory fibroid polyps (IFP) are mesenchymal tumours of the gastrointestinal tract. This study was performed to broaden the base of evidence of the pathogenic role of PDGFR mutations in IFP with particular regard to clinicopathological data and mutational patterns among IFP subtypes. Methods and results: Molecular analysis of 38 tumours revealed activating mutations in three different exons of PDGFRA in 25 IFP. For the first time we report two cases with PDGFRA‐exon 14 mutations (p.N659K; p.[N659K(+)T665A]). The results of our study and cases reported earlier indicate clearly that there is a localization‐specific pattern: exon 12 mutations predominate in the small intestine, while exon 18 mutations occur frequently in the stomach (P < 0.001). Codons 567–571 of PDGFRA represent an IFP specific mutational hot spot and are affected most frequently by deletions. Furthermore, in our series IFP of the stomach share common features. In contrast to intestinal IFP, gastric tumours occur at higher age, show heavy inflammation and tend to be smaller. IFP located in the small intestine are frequently associated with intussusception. Conclusion: We conclude that there is a ‘small bowel’ and a ‘gastric’ phenotype of IFPs which are associated with exon 12 and exon 18 PDGFRA mutations, respectively.     

Effect of glycoprotein IIb/IIIa inhibition without thrombolytic therapy on reperfusion in acute myocardial infarction: results of ReoMI pilot study.

The efficacy of abciximab and moderate dose heparin in attaining reperfusion in acute MI was tested in a multicenter pilot study. Patients with acute MI of less than 6-hr onset triaged to primary PTCA received intravenous abciximab bolus and infusion and heparin (70 u/kg) in the emergency room. Mean time to angiography from administration of abciximab was 34 +/- 23 min. TIMI flow rates were: grade 0-62%, grade I-20%, grade II-9%, and grade III-9%. Primary PTCA was performed with 100% success rate. Access site bleeding occurred in 10% of patients with no incidence of intracranial bleeding. TIMI II/III flow rates were 50% in a patient subset where angiography was delayed by 45 min. While not an alternative to thrombolytics in AMI, abciximab administration in the emergency room in patients triaged to PTCA may be beneficial in situation where door to needle time is delayed as TIMI II/III flows may be attained in some patients. Cathet. Cardiovasc. Intervent. 48:430-434, 1999.     

A transgenic Plasmodium falciparum NF54 strain that expresses GFP–luciferase throughout the parasite life cycle

Plasmodium falciparum is the pathogenic agent of the most lethal of human malarias. Transgenic P. falciparum parasites expressing luciferase have been created to study drug interventions of both asexual and sexual blood stages but luciferase-expressing mosquito stage and liver stage parasites have not been created which has prevented the easy quantification of mosquito stage development (e.g. for transmission blocking interventions) and liver stage development (for interventions that prevent infection). To overcome this obstacle, we have created a transgenic P. falciparum NF54 parasite that expresses a GFP–luciferase transgene throughout the life cycle. Luciferase expression is robust and measurable at all life cycle stages, including midgut oocyst, salivary gland sporozoites and liver stages, where in vivo development is easily measurable using humanized mouse infections in conjunction with an in vivo imaging system. This parasite reporter strain will accelerate testing of interventions against pre-erythrocytic life cycle stages.