Résumé
Background@#Malignant pleural effusion (MPE) is a complicated condition of patients with advanced tumors. Further dissecting the microenvironment of infiltrated immune cells and malignant cells are warranted to understand the immune-evasion mechanisms of tumor development and progression.@*Methods@#The possible involvement of microRNAs (miRNAs) in malignant pleural fluid was investigated using small RNA sequencing. Regulatory T cell (Treg) markers (CD4, CD25, forkhead box P3), and Helios (also known as IKAROS Family Zinc Finger 2 [IKZF2]) were detected using flow cytometry. The expression levels of IKZF2 and miR-4772-3p were measured using quantitative real-time reverse transcription polymerase chain reaction. The interaction between miR-4772-3p and Helios was determined using dual-luciferase reporter assays. The effects of miR-4772-3p on Helios expression were evaluated using an in vitro system. Correlation assays between miR-4772-3p and functional molecules of Tregs were performed.@*Results@#Compared with non-malignant controls, patients with non-small cell lung cancer had an increased Tregs frequency with Helios expression in the MPE and peripheral blood mononuclear cells. The verified downregulation of miR-4772-3p was inversely related to the Helios+ Tregs frequency and Helios expression in the MPE. Overexpression of miR-4772-3p could inhibit Helios expression in in vitro experiments. However, ectopic expression of Helios in induced Tregs reversed the effects induced by miR-4772-3p overexpression. Additionally, miR-4772-3p could regulate Helios expression by directly targeting IKZF2 mRNA.@*Conclusion@#Downregulation of miR-4772-3p, by targeting Helios, contributes to enhanced Tregs activities in the MPE microenvironment.
Résumé
Objective To investigate the phenotypic and functional properties of in vitro-induced He-lios+regulatory T cells(Helios+iTreg) and to analyze the differences between Helios+iTreg and Helios+thymic-derived natural Treg (Helios+nTreg). Methods CD4+CD25- effector T cells (CD4+CD25- Teff) that were separated from healthy subjects were cultured with anti-CD3 and anti-CD28 antibodies and stimulated with IL-2 and TGF-β to induce the generation of Helios+iTreg. Flow cytometry and real-time PCR were respectively used to analyze the differences in phenotype and CpG methylation in Treg-specific demethylated region (TSDR) be-tween Helios+iTreg and Helios+nTreg derived from the same donor. Results CD45RA was highly expressed on Helios+iTreg, but not on Helios+nTreg. Additionally, Helios+iTreg expressed significantly higher levels of CD127,ICOS and PD-1,but lower levels of CXCR3,CCR4 and CD25 than Helios+nTreg did. IFN-γ and IL-2 that expressed by Helios+iTreg were more than those by Helios+nTreg. It was also found that the level of CpG methylation in TSDR was much higher in Helios+iTreg than in Helios+nTreg. Conclusion Both nTreg and iTreg expressed Helios,but the phenotypic and functional properties of the two Treg subsets were different. It was suggested that Helios+iTreg and Helios+nTreg might play different roles in the immune system.
Résumé
A method to identify the three cryptic species of Protesilaus, (Lepidoptera: Papilionidae) from southern Brazil, based on genital morphology. I describe the male genital structures of three species of butterflies from Rio Grande do Sul, Brazil. Their external patterns do not differ enough to determine one species from another. All inhabit the same areas at the same time of the year. In an attempt to find a constant difference among them, as well as to establish the range of variability in each species, series of butterflies from different localities were dissected. The diagnostic structures found in all three species were named and drawn for their identification. Color patterns, width, separateness and presence or absence of the black bands and the color of the frons are not useful for recognizing P. nigricornis from P. stenodesmus or P. helios. The species group studied shows major morphological variability. For that reason, species level identification can be extremely difficult, particularly if the specimens are deteriorated. In conclusion, the only reliable way to correctly identify this species is by dissection of male genitalia. Rev. Biol. Trop. 55 (2): 665-671. Epub 2007 June, 29.
Analizo la estructura genital de los machos de tres especies de Protesilaus de Río Grande du Sul en Brasil, debido a que los caracteres morfológicos externos no proporcionan la información suficiente para identificarlas hasta el nivel de especie. Las tres especies se pueden encontrar en zonas de simpatría y en los mismos meses del año. Se nombraron y dibujaron las estructuras diagnósticas para cada una de las especies. Características morfológicas externas como el grosor, separación y presencia o ausencia de las bandas negras, y los colores en la cabeza, no son útiles para separar a P. nigricornis de P. stenodesmus y de P. helios. El grupo presenta una alta variabilidad morfológica, por lo que identificarlas a nivel de especie puede resultar difícil, principalmente si los especímenes se encuentran deteriorados. La identificación confiable se debe realizar mediante el estudio de los órganos genitales de los machos.