• Title/Summary/Keyword: cell infection

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Clinical and preclinical tolerance protocols for vascularized composite allograft transplantation

  • Yang, Jerry Huanda;Johnson, Ariel C.;Colakoglu, Salih;Huang, Christene A.;Mathes, David Woodbridge
    • Archives of Plastic Surgery
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    • v.48 no.6
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    • pp.703-713
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    • 2021
  • The field of vascularized composite allografts (VCAs) has undergone significant advancement in recent decades, and VCAs are increasingly common and accepted in the clinical setting, bringing hope of functional recovery to patients with debilitating injuries. A major obstacle facing the widespread application of VCAs is the side effect profile associated with the current immunosuppressive regimen, which can cause a wide array of complications such as infection, malignancy, and even death. Significant concerns remain regarding whether the treatment outweighs the risk. The potential solution to this dilemma would be achieving VCA tolerance, which would allow recipients to receive allografts without significant immunosuppression and its sequelae. Promising tolerance protocols are being studied in kidney transplantation; four major trials have attempted to withdraw immunosuppressive treatment with various successes. The common theme in all four trials is the use of radiation treatment and donor cell transplantation. The knowledge gained from these trials can provide valuable insight into the development of a VCA tolerance protocol. Despite similarities, VCAs present additional barriers compared to kidney allografts regarding tolerance induction. VCA donors are likely to be deceased, which limits the time for significant pre-conditioning. VCA donors are also more likely to be human leukocyte antigen-mismatched, which means that tolerance must be induced across major immunological barriers. This review also explores adjunct therapies studied in large animal models that could be the missing element in establishing a safe and stable tolerance induction method.

The Bcl-2/Bcl-xL Inhibitor ABT-263 Attenuates Retinal Degeneration by Selectively Inducing Apoptosis in Senescent Retinal Pigment Epithelial Cells

  • Wonseon Ryu;Chul-Woo Park;Junghoon Kim;Hyungwoo Lee;Hyewon Chung
    • Molecules and Cells
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    • v.46 no.7
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    • pp.420-429
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    • 2023
  • Age-related macular degeneration (AMD) is one of the leading causes of blindness in elderly individuals. However, the currently used intravitreal injections of anti-vascular endothelial growth factor are invasive, and repetitive injections are also accompanied by a risk of intraocular infection. The pathogenic mechanism of AMD is still not completely understood, but a multifactorial mechanism that combines genetic predisposition and environmental factors, including cellular senescence, has been suggested. Cellular senescence refers to the accumulation of cells that stop dividing due to the presence of free radicals and DNA damage. Characteristics of senescent cells include nuclear hypertrophy, increased levels of cell cycle inhibitors such as p16 and p21, and resistance to apoptosis. Senolytic drugs remove senescent cells by targeting the main characteristics of these cells. One of the senolytic drugs, ABT-263, which inhibits the antiapoptotic functions of Bcl-2 and Bcl-xL, may be a new treatment for AMD patients because it targets senescent retinal pigment epithelium (RPE) cells. We proved that it selectively kills doxorubicin (Dox)-induced senescent ARPE-19 cells by activating apoptosis. By removing senescent cells, the expression of inflammatory cytokines was reduced, and the proliferation of the remaining cells was increased. When ABT-263 was orally administered to the mouse model of senescent RPE cells induced by Dox, we confirmed that senescent RPE cells were selectively removed and retinal degeneration was alleviated. Therefore, we suggest that ABT-263, which removes senescent RPE cells through its senolytic effect, has the potential to be the first orally administered senolytic drug for the treatment of AMD.

Polarization of THP-1-Derived Macrophage by Magnesium and MAGT1 Inhibition in Wound Healing

  • Mun Ho Oh;JaeHyuk Jang;Jong Hun Lee
    • Archives of Plastic Surgery
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    • v.50 no.4
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    • pp.432-442
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    • 2023
  • Background Macrophages play a major role in wound healing and prevent infection from the outside. Polarization conversion of macrophages regulates aspects of inflammation, and two macrophages, M1 (classically activated) and M2 (alternatively activated), exist at both ends of broad-spectrum macrophage polarization. Thus, we aimed to investigate whether macrophage polarization can be artificially regulated. To this end, MgSO4 and small-interfering RNA (siRNA) targeting magnesium transport 1 (MAGT1) were used to investigate the effects of intracellular magnesium (Mg2+) concentrations on the differentiation of macrophages in vitro. Methods THP-1 derived macrophages maintained in a culture medium containing 5 mM MgSO4 and siRNA to inhibit the expression of MAGT1. As comparative groups, THP-1 derived macrophages polarized into M1 and M2 macrophages by treatment with M1, M2 inducer cytokine. The polarization status of each group of cells was confirmed by cell surface antigen expression and cytokine secretion. Results We found that MgSO4 treatment increased CD163 and CD206, similar to the effect noted in the M2 group. The expression of CD80 and HLA-DR was increased in the group treated with MAGT1 siRNA, similar to the effect noted in the M1 group. Functional assays demonstrated that the group treated with MgSO4 secreted higher levels of IL-10, whereas the MAGT1 siRNA-treated group secreted higher levels of IL-6 cytokines. Additionally, the conditional medium of the Mg2+ treated group showed enhanced migration of keratinocytes and fibroblasts. Conclusion Mg2+ can help to end the delay in wound healing caused by persistent inflammation in the early stages.

Interferon-β alleviates sepsis by SIRT1-mediated blockage of endothelial glycocalyx shedding

  • Suhong Duan;Seung-Gook Kim;Hyung-Jin Lim;Hwa-Ryung Song;Myung-Kwan Han
    • BMB Reports
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    • v.56 no.5
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    • pp.314-319
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    • 2023
  • Sepsis is a life-threatening multi-organ dysfunction with high mortality caused by the body's improper response to microbial infection. No new effective therapy has emerged that can adequately treat patients with sepsis. We previously demonstrated that interferon-β (IFN-β) protects against sepsis via sirtuin 1-(SIRT1)-mediated immunosuppression. Another study also reported its significant protective effect against acute respiratory distress syndrome, a complication of severe sepsis, in human patients. However, the IFN-β effect cannot solely be explained by SIRT1-mediated immunosuppression, since sepsis induces immunosuppression in patients. Here, we show that IFN-β, in combination with nicotinamide riboside (NR), alleviates sepsis by blocking endothelial damage via SIRT1 activation. IFN-β plus NR protected against cecal ligation puncture-(CLP)-induced sepsis in wild-type mice, but not in endothelial cell-specific Sirt1 knockout (EC-Sirt1 KO) mice. IFN-β upregulated SIRT1 protein expression in endothelial cells in a protein synthesis-independent manner. IFN-β plus NR reduced the CLP-induced increase in in vivo endothelial permeability in wild-type, but not EC-Sirt1 KO mice. IFN-β plus NR suppressed lipopolysaccharide-induced up-regulation of heparinase 1, but the effect was abolished by Sirt1 knockdown in endothelial cells. Our results suggest that IFN-β plus NR protects against endothelial damage during sepsis via activation of the SIRT1/heparinase 1 pathway.

e-Pharmacophore modeling and in silico study of CD147 receptor against SARS-CoV-2 drugs

  • Nisha Kumari Pandit;Simranjeet Singh Mann;Anee Mohanty;Sumer Singh Meena
    • Genomics & Informatics
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    • v.21 no.2
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    • pp.17.1-17.12
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    • 2023
  • Coronavirus has left severe health impacts on the human population, globally. Still a significant number of cases are reported daily as no specific medications are available for its effective treatment. The presence of the CD147 receptor (human basigin) on the host cell facilitates the severe acute respiratory disease coronavirus 2 (SARS-CoV-2) infection. Therefore, the drugs that efficiently alter the formation of CD147 and spike protein complex could be the right drug candidate to inhibit the replication of SARS-CoV-2. Hence, an e-Pharmacophore model was developed based on the receptor-ligand cavity of CD147 protein which was further mapped against pre-existing drugs of coronavirus disease treatment. A total of seven drugs were found to be suited as pharmacophores out of 11 drugs screened which was further docked with CD147 protein using CDOCKER of Biovia discovery studio. The active site sphere of the prepared protein was 101.44, 87.84, and 97.17 along with the radius being 15.33 and the root-mean-square deviation value obtained was 0.73 Å. The protein minimization energy was calculated to be -30,328.81547 kcal/mol. The docking results showed ritonavir as the best fit as it demonstrated a higher CDOCKER energy (-57.30) with correspond to CDOCKER interaction energy (-53.38). However, authors further suggest in vitro studies to understand the potential activity of the ritonavir.

Fine Mapping of Zenith Derived Rice Stripe Virus Resistance Gene, Stv-b

  • Sais-Beul Lee;Jun-Hyun Cho;Nkulu Rolly Kabange;Sumin Jo;Ji-Yoon Lee;Yeongho Kwon;Ju-Won Kang;Dongjin Shin;Jong-Hee Lee;You-Cheon Song;Jong-Min Ko;Dong-Soo Park
    • Proceedings of the Plant Resources Society of Korea Conference
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    • 2020.12a
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    • pp.63-63
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    • 2020
  • Rice stripe virus (RSV) disease is one of the major constraints in rice production, transmitted by the small brown planthopper (SBPH; Laodelphax striatellus). Upon RSV infection, plants develop typical symptoms, which include chlorosis and weakness of newly emerged leaves, white and yellow spots, stripe on leaves, and necrotic and wilting leaves, resulting in plant growth inhibition, oxidative damage that may culminate in programmed cell death (PCD) and plant death in severe epidemics. Although RSV-resistant quantitative trait loci (QTLs), Stv-a, Stv-b, and Stv-bi, were mapped using various resistant varieties, one RSV-resistant gene, OsSOT1, has been identified so far. In this study, we used the rice cultivar Zenith, known to carry Stv-b, to investigate novel RSV-genes through fine mapping. Therefore, we crossed Zenith (Donor parent, RSV resistant) with Ilpum (Recurrent parent, RSV susceptible) to fine-map using a BC2F2 population of 2100 plants. Chromosome segment introgression lines that were heterozygous at a different region were selected, two types of heterozygous lines showed an heterozygous genotype between Sid2 and Sid75 to Indel9 and RM6680. Interestingly, we identified qSTV11Z region harboring Stv-b, covering about 171-kb region between the InDel markers Sid75 and Indel8. The localization of qSTV11Z provides useful information that could be used for marker-assisted selection and determination of genetic resources in rice breeding.

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Inhibition of caspase-1-dependent apoptosis suppresses peste des petits ruminants virus replication

  • Lingxia Li;Shengqing Li;Shengyi Han;Pengfei Li;Guoyu Du;Jinyan Wu;Xiaoan Cao;Youjun Shang
    • Journal of Veterinary Science
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    • v.24 no.5
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    • pp.55.1-55.12
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    • 2023
  • Background: Peste des petits ruminants (PPR), caused by the PPR virus (PPRV), is an acute and fatal contagious disease that mainly infects goats, sheep, and other artiodactyls. Peripheral blood mononuclear cells (PBMCs) are considered the primary innate immune cells. Objectives: PBMCs derived from goats were infected with PPRV and analyzed to detect the relationship between PPRV replication and apoptosis or the inflammatory response. Methods: Quantitative real-time polymerase chain reaction was used to identify PPRV replication and cytokines expression. Flow cytometry was conducted to detect apoptosis and the differentiation of CD4+ and CD8+ T cells after PPRV infection. Results: PPRV stimulated the differentiation of CD4+ and CD8+ T cells. In addition, PPRV induced apoptosis in goat PBMCs. Furthermore, apoptosis and the inflammatory response induced by PPRV could be suppressed by Z-VAD-FMK and Z-YVAD-FMK, respectively. Moreover, the virus titer of PPRV was attenuated by inhibiting caspase-1-dependent apoptosis and inflammation. Conclusions: This study showed that apoptosis and the inflammatory response play an essential role in PPR viral replication in vitro, providing a new mechanism related to the cell host response.

Elemental characteristics of sialoliths extracted from a patient with recurrent sialolithiasis

  • Buyanbileg Sodnom-Ish;Mi Young Eo;Kezia Rachellea Mustakim;Yun Ju Cho;Soung Min Kim
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.50 no.2
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    • pp.94-102
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    • 2024
  • The exact mechanism of sialolith formation has yet to be determined. Recurrence of sialolithiasis is rare, affecting only 1%-10% of patients. The current study presents a case of recurrent stones that occurred twice on the right submandibular gland 6 months postoperative and 7 months after reoperation in a 48-year-old female patient. The stones were analyzed using histology, scanning electron microscopy, energy dispersive spectroscopy, and transmission electron microscopy (TEM). The first stone showed a three-layered structure with a poorly mineralized peripheral multilayered zone, highly mineralized middle layer, and the central nidus. The stones were composed of Ca, C, O, Cu, F, N, P, Si, Zn, and Zr. In TEM, compact bi-layered bacterial cell membrane was found on the peripheral layer and the central nidus of the stone as well as exosomes in the central nidus. The results demonstrated the essential components of sialolith formation, including bacteria, inflammatory exosomes, and exfoliated salivary epithelial cells that cooperatively underwent the pathogenetic progresses of central nidus formation, induction of compact zone calcification of the middle layer, and repeated subsequent deposition in the peripheral multilayer zone. The rapid recurrence could have resulted from residual pieces of a sialolith acting as the nidus of bacterial infection.

The ameliorating role of sofosbuvir and daclatasvir on thioacetamide-induced kidney injury in adult albino rats

  • Ahmed H. Moustafa;Heba F. Pasha;Manar A. Abas;Adel M. Aboregela
    • Anatomy and Cell Biology
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    • v.56 no.1
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    • pp.109-121
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    • 2023
  • Thioacetamide (TAA) exposure and hepatitis C virus infection are usually associated with renal dysfunction. Sofosbuvir (SFV) and daclatasvir (DAC) drugs combination has great value in the treatment of hepatitis C. The study aimed to identify the nephrotoxic effects of TAA and to evaluate the ameliorative role of SFV and DAC in this condition. Forty-eight adult male albino rats were divided into eight groups and received saline (control), SFV, DAC, SFV+DAC, TAA, TAA+SFV, TAA+DAC and TAA+SFV+DAC for eight weeks. Kidney and blood samples were retrieved and processed for histological (Hematoxylin and Eosin and Masson's trichrome), immunohistochemical (α-smooth muscle actin), and biochemical analysis (urea, creatinine, total protein, albumin, malondialdehyde, reduced glutathione, superoxide dismutase, and tumor necrosis factor-α). Examination revealed marked destruction of renal tubules on exposure to TAA with either hypertrophy or atrophy of glomeruli, increase in collagen deposition, and wide expression of α-smooth muscle actin. Also, significant disturbance in kidney functions, oxidative stress markers, and tumor necrosis factor-α. Supplementation with either SFV or DAC produced mild improvement in the tissue and laboratory markers. Moreover, the combination of both drugs greatly refined the pathology induced by TAA at the cellular and laboratory levels. However, there are still significant differences when compared to the control. In conclusion, SFV and DAC combination partially but greatly ameliorated the renal damage induced by TAA which might be enhanced with further supplementations to give new hope for those with nephropathy associated with hepatitis.

Toxoplasma gondii IST suppresses inflammatory and apoptotic responses by inhibiting STAT1-mediated signaling in IFN-γ/TNF-α-stimulated hepatocytes

  • Seung-Hwan Seo;Ji-Eun Lee;Do-Won Ham;Eun-Hee Shin
    • Parasites, Hosts and Diseases
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    • v.62 no.1
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    • pp.30-41
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    • 2024
  • The dense granule protein of Toxoplasma gondii, inhibitor of signal transducer and activator of transcription 1 (IST) is an inhibitor of signal transducer and activator of transcription 1 (STAT1) transcriptional activity that binds to STAT1 and regulates the expression of inflammatory molecules in host cells. A sterile inflammatory liver injury in pathological acute liver failures occurs when excessive innate immune function, such as the massive release of IFN-γ and TNF-α, is activated without infection. In relation to inflammatory liver injury, we hypothesized that Toxoplasma gondii inhibitor of STAT1 transcription (TgIST) can inhibit the inflammatory response induced by activating the STAT1/IRF-1 mechanism in liver inflammation. This study used IFN-γ and TNF-α as inflammatory inducers at the cellular level of murine hepatocytes (Hepa-1c1c7) to determine whether TgIST inhibits the STAT1/IRF-1 axis. In stable cells transfected with TgIST, STAT1 expression decreased with a decrease in interferon regulatory factor (IRF)-1 levels. Furthermore, STAT1 inhibition of TgIST resulted in lower levels of NF-κB and COX2, as well as significantly lower levels of class II transactivator (CIITA), iNOS, and chemokines (CLXCL9/10/11). TgIST also significantly reduced the expression of hepatocyte proapoptotic markers (Caspase3/8/9, P53, and BAX), which are linked to sterile inflammatory liver injury. TgIST also reduced the expression of adhesion (ICAM-1 and VCAM-1) and infiltration markers of programmed death-ligand 1 (PD-L1) induced by hepatocyte and tissue damage. TgIST restored the cell apoptosis induced by IFN-γ/TNF-α stimulation. These results suggest that TgIST can inhibit STAT1-mediated inflammatory and apoptotic responses in hepatocytes stimulated with proinflammatory cytokines.