Papel da proteína Mx1 na resposta a interferons e no processo neoplásico / Role of Mx1 protein in the response to interferons and neoplastic process

A proteína Mx1 é codificada por um gene induzido por interferon e compartilha a organização de seus domínios, a capacidade de homo-oligomerização e associação com membranas com as grandes dinaminas GTPases. A proteína Mx1 está envolvida na resposta contra um grande número de vírus de RNA, como aqueles pertencentes à família Buniavírus e o vírus influenza. Curiosamente, o gene MX1 foi encontrado como silenciado por metilação em diversos processos neoplásicos, incluindo carcinomas de cabeça e pescoço de células escamosas. Neste cenário, o silenciamento gênico de MX1 está associado à imortalização de uma série de linhagens celulares neoplásicas. Assim, Mx1 se destaca como uma das principais proteínas envolvidas nas respostas imunes induzidas por interferon e também desempenha um importante papel no controle do ciclo celular. Aqui discutimos os aspectos funcionais da proteína Mx1 abordando sua atividade antiviral, organização estrutural, envolvimento com neoplasias e, principalmente, os aspectos funcionais obtidos pela determinação de seus parceiros celulares.

The Mx1 protein is encoded by an interferon-induced gene and shares domain organization, homo-oligomerization capacity and membrane association with the large dynamin-like GTPases. The Mx1 protein is involved in the response to a large number of RNA viruses, such as the bunyavirus family and the influenza virus. Interestingly, it has also been found as a methylation-silenced gene in several types of neoplasm, including head and neck squamous cell carcinoma. In this scenario, MX1 gene silencing is associated with immortalization in several neoplastic cell lines. Thus, Mx1 stands out as one of the key proteins involved in interferon-induced immune response and also plays an important role in cell cycle control. Here we discuss some of the functions of the Mx1 protein, including its antiviral activity, protein folding and involvement in neoplasia, as well as those revealed by investigating its cellular partners.

Stable expression of mouse IFN-λ2 in CHO cells and its biological activity analysis / 中华微生物学和免疫学杂志

Objective To express mouse IFN-λ2 stably and study its biological activity. Methods Full-length of mIFN-λ2 cDNA was obtained by using RT-PCR from cells of mouse spleen stimulated by ve-sicular stomatitis virus(VSV) and then subcloned to eukaryotic expressing vector PCAGG-EGFP. The recom-binant was transfected into CHO cells. VSV * GFP-B16 system was used to measure the antivirus activity. The constructed cell line MDBK-Mxp-Luc was used to study the character of Mx1 protein induced by the mIFN-λ2. Results The recombinant pMD18-T-mIFN-λ2 was digested by two kinds of enzyme, Sac I and Xho I, to produce the fragment was of 582 bp, and of which the sequence analysis of sequence shows it was entirely consistent with the nucleotide sequences reported in GenBank. PCAGG-EGFP-mIFN-λ2 eukaryotic expressing vector was constructed successfully and expressed stably in CHO cells, and the mRNA of mIFN-λ2 was verified expressing in CHO-PCAGG-EGFP-mIFN-λ2 cell line by RT-PCR. The antivirus activity of in the supernatant secreted by the CHO-PCAGG-EGFP-mIFN-λ2 cell line was 10~4 AU/ml. The mIFN-λ2 pro-tein can could induce the expression of the antivirus protein Mx1, and the expression of Mx1 protein induced by mIFN-λ2 enhanced with time going, 9 to 12 hours achieved the peak, 24 hours vanished. Conclusion Gene cloning of mIFN-λ2 was successful. The eukaryotic expressing vector of mIFN-λ2 was constructed suc-cessfully and expressed stably in CHO cells, and its product has obvious antivirus activity in vitro. And the antivirus activity of the product was closely correlated with inducing expression of antivirus protein Mx1.

Terminal Bacterial Pollution of Hospital Central Oxygen Supply Equipment and Sanitizing Effect of MX-1 Disinfector / 中华医院感染学杂志

OBJECTIVE To investigate the terminal bacterial pollution of hospital central oxygen supply system and the sanitizing effect of MX-1 disinfector. METHODS Timing many spot samples of terminal oxygen supply equipment (oxygen flowmeter, humid bottle, oxygen pipe) were quantified and cultivated through 24 hours continue supply. RESULTS Five cases of timing many spot samples testified that there were no bacteria oxygen pollution in the pipe oxygen supply in the Department of Respiratory Disease, the Second Affiliated Hospital of Dalian Medical University, and that there were no bacteria pollution in the terminal oxygen supply equipments if they were sterilized strictly, but there would be severe bacteria pollution if they were not sterilized strictly. This test found that lid of humid bottle and lapis were the main source of bacteria pollution. Connection with MX-1 disinfector in the terminal can avoid bacteria pollution. CONCLUSIONS Severe bacteria pollution will happen if the oxygen supply equipments aren't sterilized strictly; connection with MX-1 disinfector in the terminal can avoid bacteria pollution and ensure oxygen for cleanliness and safety.