Interleukin-1B(1L-1B) polymorphisms and gastric mucosal levels of IL-Iβ cytokine in Korean patients with gastric cancer

Chang, Young-Woon,Jang, Jae-Young,Kim, Nam-Hoon,Lee, Jae Won,Lee, Hyo Jung,Jung, Woon Won,Dong, Seok-Ho,Kim, Hyo-Jong,Kim, Byung-Ho,Lee, Joung-Il,Rin Chang KYUNG HEE UNIVERSITY MEDICAL CENTER 2006 고황의학상 수상논문집 Vol.21-22 No.-

Interleukin-1B and IL-1 receptor antagonist gene polymorphisms are associated with an increased risk of gastric cancer (GC) in Caucasian populations. However, recent studies could not find any association between IL-1B-511T polymorphism and the risk of GC in Asians. We tested for an association between IL-1 loci polymorphisms with increased gastric mucosal levels of IL-1β and an increased risk of developing GC in a Korean population. Polymorphisms of IL-1A-889, IL-1B-31, IL-1B-511 and IL-1RN were genotyped in 434 controls and 234 patients with GC. Mucosal IL-1β cytokine was measured using an ELISA. The frequencies of IL-1A, IL-1B-511, IL-1B-31 and IL-1RN were not statistically different between controls and all patients with GC. After subclassification of GC, only patients with intestinal-type GC showed a higher frequency of IL-1B-31T homozygotes (OR = 2.2; 95% CI = 1.1-4.3) compared with controls. Risk was also significantly increased in these patients for IL-1B-31T homozygotes compared with patients with diffuse-type GC (OR = 3.4; 95% CI = 1.5-7.7). As in Caucasian populations, linkage disequilibrium between IL-1B-31 and IL-1B-511 was nearly complete, but the pattern of haplotype related to the risk of GC (IL-1B-31T/IL-1B-511C) was opposite (IL-1B-511T/IL-1B-31C). Mucosal IL-1β levels in H. pylori-infected GC patients were higher in patients homozygous for IL-1B-31T compared with IL-1B-31C/T and IL-1B-31C/C. Thus, the combined effects of H. pylori infection and IL-1B-31T/IL-1B-511C polymorphisms with enhanced mucosal IL-1β production contributed to the development of intestinal-type GC in this Korean population.

담배 니코틴에 의한 사람 태아 성상세포에서 종양괴사인자(TNF-α)의 발현 억제작용

손일홍,이성익,양현덕,한선정,석승한,이재규,김재현,박주영,문형인,이성수,Son, Il-Hong,Lee, Sung-Ik,Yang, Hyun-Duk,Han, Sun-Jung,Suk, Seung-Han,Lee, Jai-Kyoo,Kim, Jae-Hyun,Park, Joo-Young,Moon, Hyung-In,Lee, Sung-Soo 대한화학회 2007 대한화학회지 Vol.51 No.3

니코틴은 사람 대식세포에서 interleukin 2 (IL-2)와 종양괴사인자 (tumor necrosis factor-alpha; TNF-α) 가 생성되는 것을 억제하는데, 이러한 억제작용은 cytokine 유전자 발현 중 전사단계에서 전사인자의 활성을 억제함으로써 일어난다. 이러한 니코틴의 면역반응 억제작용은 아프타성궤양 및 궤양성대장염, 알레르기성폐 포염, 건초열 등에서도 보고되고 있다. 만일 중추신경계에서도 위와 같은 니코틴의 면역억제 작용이 일어난 다면 다발성경화증과 같은 면역반응 매개질환의 치료에 새로운 전기가 마련될 수 있을 것이다. 본 연구에서 는 중추신경계의 여러 면역반응 매개질환의 병태생리에 대한 이해를 넓히고자, 이미 알려진 니코틴의 cytokine 생성억제가 사람 중추신경계의 성상세포에서도 일어남을 확인하고 그 억제기전을 밝히고자 하였다. 이를 위 하여 사람 태아 성상세포에 다양한 농도의 니코틴과 IL-1β를 처리한 다음 TNF-α mRNA의 발현 정도와 NF- κB의 활성을 비교, 분석하여 다음과 같은 결과를 얻었다. 1. 사람 태아 성상세포를 0.1-20 μg/ml의 니코틴으로 처리해 본 결과 10 μg/ml 이상의 농도에서 세포독성능이 나타나기 시작하였다. 2. 사람 태아 성상세포에 IL- 1β를 처리하면 2시간만에 TNF-α mRNA가 최대로 발현되었으며 그 이후로는 점진적으로 감소하였다. 3. 사 람 태아 성상세포를 1 및 0.1 μg/ml의 니코틴으로 전처리한 후 IL-1β로 자극한 군에서는 IL-1β 단독 처리군에 비해 TNF-α mRNA의 발현이 감소하는 양상을 보였다. 1 μg/ml의 니코틴을 처리한 경우에는 8시간 이후부터 TNF-α mRNA의 발현이 현저하게 감소하여 12시간에 최대로 감소하였다. 또한 0.1 μg/ml의 니코틴을 처리한 군에서는 24시간에 가장 현저하게 감소하였다. 4. 성상세포에 IL-1β로 처리한 군에서는 강력한 NF-κB의 활성 을 확인할 수 있었으며, 니코틴을 전처리하고 IL-1β 자극한 군에서는 NF-B의 활성이 감소하였다. 결론적으로 일정농도 이상의 니코틴은 세포독성효과를 나타내나 적정한 농도와 시간 경과후 니코틴은 사람 태아 성상세포에서 IL-1β에 의해 유도되는 TNF-α의 발현 감소를 유도하며, 이는 NF-κB의 활성을 감소시킴으로써 나타난다고 생각된다. The Tumor necrosis factor-α, (TNF-α), is involved in the pathogenesis of multiple sclerosis and contributes to the degeneration of oligodendrocytes as well as neurons. Nicotine has been found to have immunosuppressive and inflammation-suppressing effects. Astrocytes, the major glial cells in the CNS, are capable of producing TNF-α at both the mRNA and protein levels in response to interleukin-1 (IL-1) or TNF-α. Nicotine has been shown to influence glial cell functions. To order to explore the role of astrocytes in the production of TNF-α, astrocytes were pretreated with nicotine and are stimulated with IL-1β to determine their effects on TNF-α production. The results are as follows. Cytotoxic effects of nicotine on human fetal astrocytes were noted above 10 μg/ml of nicotine. The effect of IL-1β on TNF-α mRNA expression in primary cultured human fetal astrocytes was maximal at 2 h after IL- 1β(100 pg/ml) treatment. Human fetal astrocytes were pretreated with 0.1, 1, and 10 μg/ml of nicotine and then stimulated with IL-1β (100 pg/ml) for 2 h. The inhibitory effect of nicotine on expressions of TNF-α mRNA in human fetal astrocytes with pretreated 0.1 μg/ml of nicotine is first noted at 8 hr, and the inhibitory effect is maximal at 12 h. The inhibitory effect at 1 μg/ml of nicotine is inhibited maximal at 24 h. Nicotine at 0.1, 1 and 10 μg/ml concentrations significantly inhibits IL-1β-induced NF-κB activation. Collectively, this study indicates that nicotine might inhibit the expression of TNF-α in activated human fetal astrocytes.

The enhanced IL-l8 production by UVB irradiation requires ROI and AP-1 signaling in human keratinocyte cell line (HaCaT)

Cho, Daeho,Kang, Jae Seung,Park, Jong Hoon,Kim, Young-In,Hahm, Eunsil,Lee, Junechul,Yang, Yoolhee,Jeon, Junho,Song, HyunKeun,Park, Hyunjeong,Kim, Taesung,Pang, Saic,Kim, Chul-Woo,Hwang, Young Il,Lee, 전남대학교 약품개발연구소 2002 약품개발연구지 Vol.11 No.-

Based on our recent observation that enhanced IL-18 expression positively correlates with malignant skin tumors, such as SCC and melanoma, we examined the possible role of UVB, known to be associated with skin cancer development, in the enhancement of IL-18 production using primary human epidermal keratinocytes and human cell line HaCaT. After cells were exposed to UVB irradiation in vitro, IL-18 production was examined by Northern blot analysis and ELISA, and it was found that IL-18 production is enhanced by UVB irradiation in a dose- and time-dependent manner. In addition, we confirmed that it is functionally active form of IL-18 using the inhibitor of caspase-1. The effect of UVB irradiation was blocked by antioxidant, N-acetyl-ι-cysteine (NAC), which suggested the involvement of reactive oxygen intermediates (ROI) in the signal transduction of UVB irradiation-enhanced IL-18 synthesis. We also found that UVB irradiation increased AP-1 binding activity by using EMSA with AP-1-specific oligonucleotide. Furthermore, inhibitors of UVB-induced AP-1 activity, such as PD98059, blocked enhanced IL-18 production, indicating that AP-1 activation is required for UVB-induced IL-18 production. Taken together, our results suggest that UVB irradiation-enhanced IL-18 production is selectively mediated through the generation of ROI and the activation of AP-1.

The Correlation of Serum IL-12B Expression With Disease Activity in Patients With Inflammatory Bowel Disease

Lee, Hye Won,Chung, Sook Hee,Moon, Chang Mo,Che, Xiumei,Kim, Seung Won,Park, Soo Jung,Hong, Sung Pil,Kim, Tae Il,Kim, Won Ho,Cheon, Jae Hee Williams & Wilkins Co 2016 Medicine Vol.95 No.23

<▼1><P>Supplemental Digital Content is available in the text</P></▼1><▼2><P><B>Abstract</B></P><P>Genetic variants in <I>IL12B</I>, encoding the p40 subunit common in interleukin-12 (IL-12) and interleukin-23, were identified as the susceptibility loci for inflammatory bowel disease (IBD). This study aimed to identify the correlation of serum IL-12B expression with disease activity in patients with IBD and evaluate the possibility of IL-12B as a biomarker for assessing inflammatory status in IBD.</P><P>A total of 102 patients with IBD, including 38, 32, and 32 patients with Crohn's disease (CD), ulcerative colitis (UC), and intestinal Behçet's disease (intestinal BD), respectively, were included. The clinical and laboratory data from the patients were collected at the time of serum IL-12B measurement. Serum IL-12B levels were measured using an enzyme-linked immunosorbent assay.</P><P>The median IL-12B levels in patients with CD, UC, and intestinal BD were significantly higher than those in controls (1.87, 2.74, and 2.73 pg/mL, respectively, vs. 1.42 pg/mL, all <I>P</I> <0.05). IL-12B concentrations were associated with disease activity in patients with UC and intestinal BD but not in those with CD. IL-12B levels were increased with increasing disease activity in patients with UC (<I>P</I> <0.001). Likewise, patients with active intestinal BD had higher IL-12B levels than those without active disease (<I>P</I> = 0.008). IL-12B levels were correlated with the endoscopic disease activity of UC (<I>P</I> = 0.002) and intestinal BD (<I>P</I> = 0.001) but not that of CD.</P><P>Serum IL-12B levels were significantly correlated with clinical and endoscopic disease activity in patients with UC and intestinal BD, suggesting its potential use as a biomarker for assessing disease activity in these patients.</P></▼2>

N-Acetyl-L-Cysteine에 의한 생쥐 골수유래 가지세포의 기능적 활성화 저해

정영주(Young-joo Jeong),맹형건(Hyung Gun Maeng),김민규(Min Kyu Kim),강재승(Jae Seung Kang),이왕재(Wang Jae Lee),황영일(Young-il Hwang) 대한해부학회 2008 Anatomy & Cell Biology Vol.41 No.2

N-acetyl-L-cysteine (NAC)은 thiol기를 포함하는 화합물로서, glutathione (GSH)의 전구체로 작용하여 포유류 세포 내에서 항산화제로 작용한다. 또한 항염기능이 있으며 호산구나 B세포, 가지세포 (dendritic cell, DC)와 같은 면역세포 들에 여러 가지 영향을 미치는 것으로 알려져 있다. 특히 가지세포에 작용하여 활성화를 억제하거나 가지세포에 의한 Th2 반응 유도에 관여한다고 알려져 있다. 그러나 이들 연구는 세부적인 사항에 있어서 그 결과가 서로 상치하는바가 많으며, 또한 조절T세포의 관점에서는 연구된 바가 없다. 따라서 본 연구에서는 NAC 처리가 가지세포 활성화에 미치는 영향을 재확인하였고, NAC 처리된 가지세포의 T세포 활성 능력 저하, 또는 Th2 반응 유도 여부를 알아보았다. 활성화 시 가지세포에서 증가하는 활성산소기 (reactive oxygen species)는 NAC 처리로 낮아져서, NAC이 가지세포에 항산화작용을 나타냄을 확인하였다. NAC 처리로 가지세포에서 보조자극인자인 CD40과 CD86의 발현이 저해되었으며, 활성화 시 정상적으로 낮아지는 포식기능은 처리된 NAC의 농도에 비례하게 보존되었다. 활성화 시 분비되는 IL-6, IL-10, IL-12는 모두 감소하였다. 이러한 NAC-DC와 함께 배양한 T세포의 증식이나 Th1 cytokine인 IFN-γ, Th2 cytokine인 IL-5의 분비가 모두 저하되어 Th1/Th2의 편중 없이 가지세포의 T세포 자극능력이 전반적으로 감소하였음을 나타내었다. 또한 T세포 배양액에서 IL-10과 TGF-β의 농도 역시 NAC-DC로 자극된 경우에 현저히 줄어서, NAC-DC에 의한 T세포 증식 감소 등은 조절T세포 유도에 의한 것이 아니라 T세포 무반응이 유도된 때문임을 나타내 주었다. N-acetyl-L-cysteine (NAC) is a thiol-containing compound and acts as a precursor for glutathione (GSH). It behaves as an antioxidant in mammalian cells and also exerts anti-inflammatory effects. NAC is also known to affect several immune cells including eosinophils, B cells, T cells, and dendritic cells (DC) in many aspects. Even though it has been reported that NAC inhibits DC activation and shifts the immune response to Th2, these studies exhibit some contradictory results in detail and do not give any information with respect to the induction of regulatory T cells. In this study, we re-analyzed the effects of NAC on DC during their activation. We also evaluated whether it induced T cell anergy, Th1/Th2 shift, or regulatory T cells. NAC suppressed the elevation of intracellular reactive oxygen species during DC activation. In parallel, it down-regulated surface expression of CD40 and CD86, suppressed the decrease of phagocytic function, lowered the secretion of cytokines such as IL-6, IL-10, and IL-12. All these effects showed dose-dependency. Thus, it seems likely that NAC inhibited DC activation with regard to their phenotype and cytokine secretion. When we evaluated the T cell-stimulating capacity of these NAC-DC, T cell proliferation and secretion of both Th1 (IFN-γ) and Th2 cytokine (IL-5) were decreased. This implies that the T cell-stimulating activity of NAC-DC decreased without any shift to Th1 or Th2 cytokine (IL-5). The secretion of IL-10 and TGF-β in the supernatants were also decreased, which suggests that the decrease of T cell proliferation and cytokine secretion is due to the induction of T cell anergy, rather than regulatory T cells.

RSV 와 인플루엔자 바이러스 A 형 감염에 의해 천명을 보이는 소아와 천식 소아에서 비인두 흡인액의 Interleukin-5 와 Interleukin-γ 치의 비교

오재원,이하백,김창렬,염명걸,문수지,박일규,강정옥 대한 소아알레르기 및 호흡기학회 1999 소아알레르기 및 호흡기학회지 Vol.9 No.2

목 적 : 호흡기 바이러스 감염은 소아에서 천식을 악화시키는 것으로 잘 알려져 있다. 그러나 영유아기의 천식이나 천명발생에 있어서 호홉기 바이러스의 역할에 대해서는 명확하게 밝혀져 있지 않다. 소아기의 천명이 천식과 달리 하나의 독립된 질환인지, 아니면 같은 질환으로 달리 표현되는 것인지 논란이 되어왔다. 이에 본 저자들은 호흡기 바이러스 감염과 천명과의 상관관계와 기전을 이해하기 위하여 RSV 감염이나 influenza A 바이러스 감염에 의해 천명이 있는 소아와 바이러스가 증명되지 않고 천명이 있는 천식소아에서의 비인두 흡인액의 IL-5와 IFN-γ치를 측정하여 비교하였다. 방 법 : 호흡기 바이러스 감염군 38명(RSV감염군 21명, influenga A virus 감염군 17명), 바이러스가 증명되지 않은 천식환아군 12명, 정상 대조군 16명을 대상으로 double sandwich ELISA를 이용하여 비인두 흡인액에서 IL-5와 IFN-γ치를 측정하여 비교하였다. 결 과 : RSV 감영군에서 비인두 흡인액의 IL-5 평균치가 influenza A 바이러스군의 평균치보다 의미있게 높았으며, 천식군보다도 높은 양상을 보이나 의미있는 차이는 없었다 반면, influenza A 바이러스 감염군의 비인두 흡인액의 IFN-γ치가 RSV군에 비해 의미있게 높았으나 천식환아군이나 정상군에 비해 의미있게 높지는 않았다. 비인두 흡입액에서 IL-5와 IFN-γ치간의 상관관계는 없었다. 결 론 : RSV 감염군은 influenza A 바이러스 감염군에 비해 Th2 반응이 우세한 것으로 추정되며, 반면에 influenza A virus 감염군은 Th1 반응을 보이는 것을 알 수 있다. Background : Infection with respiratory virus has been shown to exacerbate asthma. However, the role of a respiratory virus in the pathogenesis of chronic asthma and/or wheezing in young children has not been clearly defined. And it also has been debated whether virus-induced wheezing in young children is an entity different from allergic asthma, or just a different expression of the same disease. In this study, we attempted to evaluate the importance of eosinophilic inflammation, comparing IL-5 and IFN-γ levels in nasopharyngeal secretions in wheezing children with or without viral infection and the controls. Methods : We compared IL-5 and IFN-γ levels in nasopharyngeal secretions from 38 non-asthmatic wheezing children with viral infections (RSV in 21 children, influenza A virus in 17 children), 12 asthmatic children without viral infections and 16 children as the controls. Results : The present study reported that RSV infection in children induced more releasing of IL-5 in nasopharyngeal secretions than the influenza A virus infected ones and the controls. On the other hand, the releasing of IFN-γ levels in nasopharyngeal secretions from children with influenza A virus infection was significantly higher than those of the children with RSV infection or asthmatic children. Conclusion : RSV infection in children may play a role in the immune response toward a Th2 phenotype as increasing IL-5 secretion in nasopharyngeal secretion. Increased IFN-γ production in response to the influenza A virus infection may be related to the effective Th1 responses.

Cell source-dependent <i>in vivo</i> immunosuppressive properties of mesenchymal stem cells derived from the bone marrow and synovial fluid of minipigs

Lee, Won-Jae,Hah, Young-Sool,Ock, Sun-A.,Lee, Jae-Hoon,Jeon, Ryong-Hoon,Park, Ji-Sung,Lee, Sang-Il,Rho, Na-Young,Rho, Gyu-Jin,Lee, Sung-Lim Elsevier 2015 Experimental cell research Vol.333 No.2

<P><B>Abstract</B></P> <P>The <I>in vitro</I> differentiation and immunosuppressive capacity of mesenchymal stem cells (MSCs) derived from synovial fluid (SF-MSCs) and bone marrow extract (BM-MSCs) in an isogenic background of minipigs were comparatively analyzed in a collagen-induced arthritis (CIA) mouse model of rheumatoid arthritis (RA). The proliferation capacity and expression of pluripotent transcription factors (Oct3/4 and Sox2) were significantly (<I>P</I><0.05) higher in SF-MSCs than in BM-MSCs. The differentiation capacity of SF-MSCs into adipocytes, osteocytes and neurocytes was significantly (<I>P</I><0.05) lower than that of BM-MSCs, and the differentiation capacity of SF-MSCs into chondrocytes was significantly (<I>P</I><0.05) higher than that of BM-MSCs. Systemic injection of BM- and SF-MSCs significantly (<I>P</I><0.05) ameliorated the clinical symptoms of CIA mice, with SF-MSCs having significantly (<I>P</I><0.05) higher clinical and histopathological recovery scores than BM-MSCs. Furthermore, the immunosuppressive properties of SF-MSCs in CIA mice were associated with increased levels of the anti-inflammatory cytokine interleukin (IL)-10, and decreased levels of the pro-inflammatory cytokine IL-1β and osteoclast-related sRANKL. In conclusion, SF-MSCs exhibited eminent pluripotency and differentiation capacity into chondrocytes, addition to substantial <I>in vivo</I> immunosuppressive capacity by elevating IL-10 and reducing IL-1β levels in CIA mice.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Immunosuppressive capacity of BM-, SM-, and SF-MSCs was evaluated in an RA model. </LI> <LI> Proliferation, pluripotency and chondrogenic differentiation capacity were higher in SF-MSCs. </LI> <LI> SF-MSCs exhibited improved therapeutic effects than BM-MSCs. </LI> <LI> SF-MSCs may have applications as immunosuppressive therapy in autoimmune diseases. </LI> </UL> </P>

Glucocorticoid-induced tumor necrosis factor receptor–related protein co-stimulation facilitates tumor regression by inducing IL-9–producing helper T cells

Kim, Il-Kyu,Kim, Byung-Seok,Koh, Choong-Hyun,Seok, Jae-Won,Park, Jun-Seok,Shin, Kwang-Soo,Bae, Eun-Ah,Lee, Ga-Eun,Jeon, Hyewon,Cho, Jaebeom,Jung, Yujin,Han, Daehee,Kwon, Byoung S,Lee, Ho-Young,Chung, Nature Publishing Group, a division of Macmillan P 2015 Nature medicine Vol.21 No.9

<P>T cell stimulation via glucocorticoid-induced tumor necrosis factor receptor (TNFR)-related protein (GITR) elicits antitumor activity in various tumor models; however, the underlying mechanism of action remains unclear. Here we demonstrate a crucial role for interleukin (IL)-9 in antitumor immunity generated by the GITR agonistic antibody DTA-1. IL-4 receptor knockout (Il4ra(-/-)) mice, which have reduced expression of IL-9, were resistant to tumor growth inhibition by DTA-1. Notably, neutralization of IL-9 considerably impaired tumor rejection induced by DTA-1. In particular, DTA-1-induced IL-9 promoted tumor-specific cytotoxic T lymphocyte (CTL) responses by enhancing the function of dendritic cells in vivo. Furthermore, GITR signaling enhanced the differentiation of IL-9-producing CD4(+) T-helper (T(H)9) cells in a TNFR-associated factor 6 (TRAF6)- and NF-kappa B-dependent manner and inhibited the generation of induced regulatory T cells in vitro. Our findings demonstrate that GITR co-stimulation mediates antitumor immunity by promoting T(H)9 cell differentiation and enhancing CTL responses and thus provide a mechanism of action for GITR agonist-mediated cancer immunotherapies.</P>

Caffeic acid phenethyl ester inhibits the inflammatory effects of interleukin-1β in human corneal fibroblasts

Yang, Jae-Wook,Jung, Won-Kyo,Lee, Chang-Min,Yea, Sung Su,Choi, Yung Hyun,Kim, Gi-Young,Lee, Dae-Sung,Na, Giyoun,Park, Sae-Gwang,Seo, Su-Kil,Choi, Jung Sik,Lee, Young-Min,Park, Won Sun,Choi, Il-Whan Informa Healthcare USA, Inc. 2014 IMMUNOPHARMACOLOGY AND IMMUNOTOXICOLOGY Vol.36 No.5

<P><I>Context</I>: Expression of various inflammatory mediators in corneal fibroblasts contributes to corneal inflammation.</P><P><I>Objective</I>: The purpose of this study was to assess the possible effects of caffeic acid phenethyl ester (CAPE) on the expression of inflammatory mediators during an inflammatory response in human corneal fibroblasts.</P><P><I>Materials and methods</I>: The levels of interleukin (IL)-6, monocyte chemotactic protein (MCP)-1, and intercellular adhesion molecule-1 (ICAM-1) from IL-1β-exposed human corneal fibroblasts were measured with enzyme-linked immunosorbent assays (ELISA). The regulatory mechanisms of CAPE on cellular signaling pathways were examined using Western blot and electrophoretic mobility shift assays. A functional validation was carried out by evaluating the inhibitory effects of CAPE on neutrophil and monocyte migration <I>in vitro</I>.</P><P><I>Results</I>: CAPE inhibited the expression of IL-6, MCP-1 and ICAM-1 induced by the pro-inflammatory cytokine IL-1β in corneal fibroblasts. The activation of AKT and NF-κB by IL-1β was markedly inhibited by CAPE, whereas the activity of mitogen-activated protein kinases (MAPKs) was not affected. CAPE significantly suppressed the IL-1β-induced migration of differentiated (d)HL-60 and THP-1 cells.</P><P><I>Discussion</I>: These anti-inflammatory effects of CAPE may be expected to inhibit the infiltration of leukocytes into the corneal stroma <I>in vivo</I>.</P>

<i>In vivo</i> genotoxicity evaluation of lung cells from Fischer 344 rats following 28 days of inhalation exposure to MWCNTs, plus 28 days and 90 days post-exposure

Kim, Jin Sik,Sung, Jae Hyuck,Choi, Byung Gil,Ryu, Hyeon Yeol,Song, Kyung Seuk,Shin, Jae Hoon,Lee, Jong Seong,Hwang, Joo Hwan,Lee, Ji Hyun,Lee, Gun Ho,Jeon, Kisoo,Ahn, Kang Ho,Yu, Il Je Informa Healthcare 2014 INHALATION TOXICOLOGY Vol.26 No.4

<P>Despite their useful physico-chemical properties, carbon nanotubes (CNTs) continue to cause concern over occupational and human health due to their structural similarity to asbestos. Thus, to evaluate the toxic and genotoxic effect of multi-wall carbon nanotubes (MWCNTs) on lung cells <I>in vivo</I>, eight-week-old rats were divided into four groups (each group = 25 animals), a fresh air control (0 mg/m<SUP>3</SUP>), low (0.17 mg/m<SUP>3</SUP>), middle (0.49 mg/m<SUP>3</SUP>), and high (0.96 mg/m<SUP>3</SUP>) dose group, and exposed to MWCNTs <I>via</I> nose-only inhalation 6 h per day, 5 days per week for 28 days. The count median length and geometric standard deviation for the MWCNTs determined by TEM were 330.18 and 1.72 nm, respectively, and the MWCNT diameters ranged from 10 to 15 nm. Lung cells were isolated from five male and five female rats in each group on day 0, day 28 (only from males) and day 90 following the 28-day exposure. The total number of animals used was 15 male and 10 female rats for each concentration group. To determine the genotoxicity of the MWCNTs, a single cell gel electrophoresis assay (Comet assay) was conducted on the rat lung cells. As a result of the exposure, the olive tail moments were found to be significantly higher (<I>p</I> < 0.05) in the male and female rats from all the exposed groups when compared with the fresh air control. In addition, the high-dose exposed male and middle and high-dose exposed female rats retained DNA damage, even 90 days post-exposure (<I>p</I> < 0.05). To investigate the mode of genotoxicity, the intracellular reactive oxygen species (ROS) levels and inflammatory cytokine levels (TNF-α, TGF- β, IL-1, IL-2, IL-4, IL-5, IL-10, IL-12 and IFN-γ) were also measured. For the male rats, the H<SUB>2</SUB>O<SUB>2</SUB> levels were significantly higher in the middle (0 days post-exposure) and high- (0 days and 28 days post-exposure) dose groups (<I>p</I> < 0.05). Conversely, the female rats showed no changes in the H<SUB>2</SUB>O<SUB>2</SUB> levels. The inflammatory cytokine levels in the bronchoalveolar lavage (BAL) fluid did not show any statistically significant difference. Interestingly, the short-length MWCNTs deposited in the lung cells were persistent at 90 days post-exposure. Thus, exposing lung cells to MWCNTs with a short tube length may induce genotoxicity.</P>