• Journal of Microbiology and Biotechnology
• /
• v.29 no.6
• /
• pp.989-998
• /
• 2019

Autophagy is crucial for immune defense against Mycobacterium tuberculosis (Mtb) infection. Mtb can evade host immune attack and survival within macrophages by manipulating the autophagic process. MicroRNAs (miRNAs) are small, non-coding RNAs that are involved in regulating vital genes during Mtb infection. The precise role of miRNAs in autophagy with the exits of Mtb remains largely unknown. In this study, we found miR-1958, a new miRNA that could regulate autophagy by interacting with 3'UTR of autophagy-related gene 5 (Atg5). In addition, Mtb infection triggered miR-1958 expression in RAW264.7 cells. What's more, miR-1958 overexpression blocked autophagic flux by impairing the fusion of autophagosomes and lysosomes. Overexpression of miR-1958 reduced Atg5 expression and LC3 puncta while inhibition of miR-1958 brought an increase of Atg5 and LC3 puncta; the opposite results were observed in detection of p62. The survival of Mtb in RAW264.7 cells transfected with mimic of miR-1958 was enhanced. Taken together, our research demonstrated that a novel miR-1958 could inhibit autophagy by interacting with Atg5 and favored intracellular Mtb survival in RAW264.7 cells.

• IMMUNE NETWORK
• /
• v.21 no.3
• /
• pp.24.1-24.13
• /
• 2021

Due to the inconsistent fluctuation of blood supply for transfusion, much attention has been paid to the development of artificial blood using other animals. Although mini-pigs are candidate animals, contamination of mini-pig T cells in artificial blood may cause a major safety concern. Therefore, it is important to analyze the cross-reactivity of IL-7, the major survival factor for T lymphocytes, between human, mouse, and mini-pig. Thus, we compared the protein sequences of IL-7 and found that porcine IL-7 was evolutionarily different from human IL-7. We also observed that when porcine T cells were cultured with either human or mouse IL-7, these cells did not increase the survival or proliferation compared to negative controls. These results suggest that porcine T cells do not recognize human or mouse IL-7 as their survival factor.

• Animal cells and systems
• /
• v.5 no.4
• /
• pp.291-297
• /
• 2001

Three species of endosymbiotic dinoflagellates, zooxanthellae, are investigated from six host species of anthozoans from Korea. Three unrecorded endosymbionts species are Symbiodinium kawagutii, Symbiodinium microadriaticum, and Symbiodinium sp. Symbiodinium kawagutii Is associated with Alveopora japonica, Anthopleura japonica and Parasicyonis actinostoloides. Symbiodinium microadiraticum is found in Anthopleura kurogane and Parasicyonis sp. Unlike the former two symbionts, Symbiodinium sp. is associated with Anthopleura midori.

• Journal of Yeungnam Medical Science
• /
• v.16 no.1
• /
• pp.15-24
• /
• 1999

Although traditionally viewed as a physical barrier between the host and a variety of inhaled irritants and pathogens, it has become clear that the epithelium has a much broader functional scope. Epithelial cells arc metabolically active and can play an important role in the regulation of the allergic inflammatory response. This review provides a consideration of the role of the epithelial cell as both a "target" for exogenous and endogenous stimuli and as an "effector" cell that is capable of producing a variety of products that can influence the inflammatory response in the airways.

• Proceedings of the PSK Conference
• /
• 2003.04a
• /
• pp.214.2-215
• /
• 2003

Reactive oxygen species play an important role in aging. carcinogenesis, and certain neurological disorders of human beings in addition to the host-defensive mechanism of inflammatory response. Murine macrophages Raw264.7 released superoxide anions via NADPH oxidase complex and nitric oxide (NO) via iNOS synthase when the cells were stimulated with unopsonized zymosan binding to complement receptor. (omitted)

• International Journal of Contents
• /
• v.1 no.2
• /
• pp.31-34
• /
• 2005

The new realtime applications like multimedia and realtime services in a wireless network will be dramatically increased. However, many realtime services of mobile hosts in a cell cannot be continued because of insufficiency of useful channels. Conventional channel assignment approaches didn't properly consider the problem to serve realtime applications in a cell. This paper proposes a new realtime channel assignment algorithm based on time constraint analysis of channel requests. The proposed algorithm dynamically borrows available channels from neighboring cells. It also supports a smooth handoff which continuously serves realtime applications of the mobile hosts.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.47 no.6
• /
• pp.480-483
• /
• 2021

Tissue regeneration is one of the ultimate goals of maxillofacial surgery and various types of tissue engineering technologies have been utilized in clinics. Healthy resources of host cells and growth factors are essential for the tissue engineering, therefore autologous blood-derived cell therapy was introduced. In this article, clinical applications of the autologous platelet concentrates and stem cell separation therapy will be summarized and evaluated for their efficacy and feasibility in the current maxillofacial clinics.

• Parasites, Hosts and Diseases
• /
• v.50 no.1
• /
• pp.1-6
• /
• 2012

$Toxoplasma$ $gondii$ penetrates all kinds of nucleated eukaryotic cells but modulates host cells differently for its intracellular survival. In a previous study, we found out that serine protease inhibitors B3 and B4 (SERPIN B3/B4 because of their very high homology) were significantly induced in THP-1-derived macrophages infected with $T.$ $gondii$ through activation of STAT6. In this study, to evaluate the effects of the induced SERPIN B3/B4 on the apoptosis of $T.$ $gondii$-infected THP-1 cells, we designed and tested various small interfering (si-) RNAs of SERPIN B3 or B4 in staurosporine-induced apoptosis of THP-1 cells. Anti-apoptotic characteristics of THP-1 cells after infection with $T.$ $gondii$ disappeared when SERPIN B3/B4 were knock-downed with gene specific si-RNAs transfected into THP-1 cells as detected by the cleaved caspase 3, poly-ADP ribose polymerase and DNA fragmentation. This anti-apoptotic effect was confirmed in SERPIN B3/B4 overexpressed HeLa cells. We also investigated whether inhibition of STAT6 affects the function of SERPIN B3/B4, and vice versa. Inhibition of SERPIN B3/B4 did not influence STAT6 expression but SERPIN B3/B4 expression was inhibited by STAT6 si-RNA transfection, which confirmed that SERPIN B3/B4 was induced under the control of STAT6 activation. These results suggest that $T.$ $gondii$ induces SERPIN B3/B4 expression via STAT6 activation to inhibit the apoptosis of infected THP-1 cells for longer survival of the intracellular parasites themselves.

• KSBB Journal
• /
• v.11 no.2
• /
• pp.254-261
• /
• 1996

Attenuated varicella-zoster virus (VZV) was propagated in human lung fibroblast (HLF) cells Among media tested in this work, DMEM was the best medium for the growth of HLF cells. Because HLF was a normal finite cell line, cell growth late was dependent on the age of HLF cells. When the population doubling level (PDL) was higher than 46, apoptosis of HLF cells started and cell growth rate decreased. The optimum temperature for the cell growth and virus propagation in the T-flask culture was $37^{\circ}C$. In a microcarrier culture system in which Cytodex-3 was used for the VZV propagation in spinner vessels, the yield of plaque forming cells was lower than that in the T-flask culture. The relatively high shear environment near microcarriers was thought to cause the low yield of VZV in the microcarrier culture system.

• The Journal of the Korean Society for Microbiology
• /
• v.34 no.5
• /
• pp.479-489
• /
• 1999

Invasion of enteric bacteria, such as Salmonella and invasive E. coli, into intestinal epithelial cells induces proinflammatory gene responses and finally epithelial cell apoptosis. In this study, we asked whether invasive bacterial infection of human intestinal epithelial cells could upregulate cyclooxygenase-2 (COX-2) gene expression and whether increased COX-2 expression could influence intestinal epithelial cell apoptosis. Expression of COX-2 mRNA and prostaglandin (PG) $E_2$ production were upregulated in HT-29 colon epithelial cells which were infected with S. dublin or invasive E. coli, as examined by quantitative RT-PCR and radioimmunoassay. Inhibition of COX-2 expression and $PGE_2$ production using NS-398, a specific COX-2 inhibitor, showed a significant increase of epithelial cell apoptosis and caspase-3 activation in HT-29 cells infected with invasive bacteria. However, the addition of valerylsalicylate, a specific COX-1 inhibitor, did not change apoptosis in S. dublin-infected HT-29 cells. These results suggest that up regulated COX-2 expression and $PGE_2$ production in response to invasive bacterial infection could contribute to host defense by inhibiting apoptosis of intestinal epithelial cells.