en Molecular Microbiology Molecular Microbiology مقاله کامل Full Length/Original Article <span style="font-family:Times New Roman;"><span style="font-size:11pt"><span style="line-height:normal"><span calibri=""><b><span style="font-size:10.5pt">Background:</span></b> <span style="font-size:10.5pt">Autophagy induction has been shown to differ in magnitude depending on the mycobacterial species. However, few studies have investigated the specific autophagic capacity of different </span><i><span style="font-size:10.5pt"><span style="color:black">Mycobacterium tuberculosis</span></span></i><i> </i><span style="font-size:10.5pt">(</span><i><span style="font-size:10.5pt">Mtb</span></i><span style="font-size:10.5pt">)</span><span style="font-size:10.5pt"> strains in </span><span style="font-size:10.5pt"><span style="color:black">alveolar epithelial cells</span></span><span style="font-size:10.5pt"> (ATs). This study aimed to elucidate the host autophagic response to different <i>Mtb</i> strains in ATs responsible for TB in the capital of Iran, Tehran. &nbsp;</span></span></span></span><br> <span style="font-size:11pt"><span style="line-height:normal"><span calibri=""><b><span style="font-size:10.5pt">Methods:</span></b> <span style="font-size:10.5pt">A549 cells were infected with three different <i>Mtb</i> clinical isolates (Beijing, NEW1, and CAS1/Delhi) and the reference strain H37Rv. Following RNA extraction, the expression of eight ATG genes, four mycobacterial genes, and three miRNAs was evaluated using quantitative RT-PCR.</span><b> </b>&nbsp;</span></span></span><br> <span style="font-size:11pt"><span style="line-height:normal"><span calibri=""><b><span style="font-size:10.5pt">Results:</span></b> <span style="font-size:10.5pt">The results revealed that all four strains influenced the autophagy pathway in various ways at different magnitudes. The Beijing and H37Rv</span> <span style="font-size:10.5pt">strains could inhibit autophagosome formation, whereas the CAS and NEW1 strains induced autophagosome formation. The expression of genes involved in the fusion of autophagosomes to lysosomes (LAMP1) indicated that all the studied strains impaired the autophagolysosomal fusion; this result is not unexpected as <i>Mtb</i> can block the autophagolysomal fusion. In addition, the Beijing and H37RV strains prevented the formation of autophagic vacuoles, besides mycobacterial targeting of lysosomes and protease activity.</span></span></span></span><br> <b><span style="font-size:10.5pt"><span style="line-height:115%"><span calibri="">Conclusion:</span></span></span></b> <span style="font-size:10.5pt"><span style="line-height:115%"><span calibri="">This preliminary study improved our understanding of how <i>Mtb</i> manages to overcome the host immune system, such as autophagy, and evaluated the genes used by specific strains during this process. Further studies with a large number of <i>Mtb</i> strains, encompassing the other main <i>Mtb</i> lineages, are inevitable.</span></span></span></span> A549 cells, Autophagy, MicroRNA, Mycobacterium tuberculosis 313 323 http://ibj.pasteur.ac.ir/browse.php?a_code=A-10-4741-1&slc_lang=en&sid=1 Nasim Ebrahimifard ebrahimimehr90@yahoo.com 0000-0000-0000-0000 No Pasteur Institute of Iran Shima Hadifar shima_hadifar@yahoo.com 0000-0003-4702-634X No Pasteur Institute of Iran Mansour Kargarpour Kamakoli mansour_kargarpour@yahoo.com 0000-0002-8588-6407 No Pasteur Institute of Iran Ava Behrouzi ava.behrouzi@gmail.com 0000-0001-8677-6851 No Pasteur Institute of Iran Sharareh Khanipour khanipour@pasteur.ac.ir.com 0000-0000-0000-0000 No Pasteur Institute of Iran Abolfazl Fateh fateh-a@pasteur.ac.ir 0000-0002-2043-8523 No Pasteur Institute of Iran Seyed Davar Siadat Siadat@pasteur.ac.ir 0000-0002-6892-5603 No Pasteur Institute of Iran Farzam Vaziri farzam_vaziri@yahoo.com 0000-0001-7788-2548 Yes Pasteur Institute of Iran