Geographic diversity in Helicobacter pylori oipA genotype between Korean and United States isolates

Kim Aeryun,Lai Jing,Merrell D. Scott,Kim Ji-Hye,Su Hanfu,Cha Jeong-Heon 한국미생물학회 2021 The journal of microbiology Vol.59 No.12

Helicobacter pylori outer membrane inflammatory protein A (OipA) was originally named for its role in inducing inflammation in the host, as evidenced by high mucosal IL-8 levels. Expression of OipA is regulated by phase variation of a CT dinucleotide-repeat located in the 5 region of the gene. However, little is known about OipA geographic diversity across isolates. To address this gap, we conducted a large-scale molecular epidemiologic analysis using H. pylori clinical isolates obtained from two geographically distinct populations: Korea and the United States (US). Most Korean isolates (98.7%) possessed two copies of oipA located at two specific loci (A and B) while all US isolates contained only one copy of oipA at locus A. Furthermore, most Korean oipA (94.8%) possessed three or less CT repeats while most US oipA (96.6%) contained five or more CT repeats. Among the two copies, all Korean H. pylori possessed at least one oipA ‘on’ phase variant while the single copy of oipA in US isolates showed 56.2% ‘on’ and 43.8% ‘off.’ Thus, host differences seem to have driven geographic diversification of H. pylori across these populations such that OipA expression in US isolates is still regulated by phase variation with 5 or more CT repeats, while Korean isolates always express OipA; duplication of the oipA combined with a reduction of CT repeats to three or less ensures continued expression. En masse, these findings suggest that diversity in the oipA gene copy number, CT repeats, and phase variation among H. pylori from different populations may confer a benefit in adaptation to particular host populations.

Osteoblast differentiation in customized human periodontal ligament cells

Aeryun Kim,Yu-Mi Yang,Da Hye Jeong,Yun-Jung Yoo,Eun-Jung Bak 한국실험동물학회 2018 한국실험동물학회 학술발표대회 논문집 Vol.2018 No.1

Role of γ-glutamyltranspeptidase in osteoclastogenesis induced by Fusobacterium nucleatum

Kim, Aeryun,Kim, Ji-Hye The Korean Academy of Oral Biology 2021 International Journal of Oral Biology Vol.46 No.3

We previously showed that γ-glutamyltranspeptidase (GGT), an enzyme involved in glutathione metabolism, in Bacillus subtilis acts as a virulence factor for osteoclastogenesis via the RANKL-dependent pathway. Hence, it can be hypothesized that GGT of periodontopathic bacteria acts as a virulence factor in bone destruction. Because Fusobacterium nucleatum, which is a periodontopathic pathogen, has GGT with a primary structure similar to that of B. subtilis GGT (37.7% identify), the bone-resorbing activity of F. nucleatum GGT was examined here. Recombinant GGT (rGGT) of F. nucleatum was expressed in Escherichia coli and purified using the His tag of rGGT. F. nucleatum rGGT (Fn rGGT) was expressed as a precursor of GGT, and then processed to a heavy subunit and a light subunit, which is characteristic of general GGTs, including the human and B. subtilis enzymes. Osteoclastogenesis was achieved in a co-culture system of mouse calvaria-derived osteoblasts and bone marrow cells. Fn rGGT induced osteoclastogenesis to a level similar to that of B. subtilis rGGT; furthermore, osteoclastogenesis was induced in a dose-dependent manner. These results suggest that F. nucleatum GGT possesses a virulent bone-resorbing activity, which could play an important role in the pathogenesis of periodontitis.

Helicobacter pylori outer membrane protein, HomC, shows geographic dependent polymorphism that is influenced by the Bab family

Aeryun Kim,Stephanie L. Servetas,Jieun Kang,Jinmoon Kim,장성일,Yun Hui Choi,Hanfu Su,Yeong-Eui Jeon,Youngmin A. Hong,유윤정,D. Scott Merrell,차정헌 한국미생물학회 2016 The journal of microbiology Vol.54 No.12

The array of outer membrane proteins (OMPs) found in Helicobacter pylori provides a crucial component for persistent colonization within the gastric niche. Not only does H. pylori harbor a wide number of OMPs, but these OMPs often vary across strains; this likely contributes to immune evasion, adaptation during long term colonization, and potentially differential disease progression. Previous work from our group described OMP differences among the Bab family (babA, babB, and babC) and Hom family (homA and homB) from 80 American H. pylori clinical isolates (AH) and 80 South Korean H. pylori clinical isolates (KH). In the current study, we expanded our investigation to include the less well characterized Hom family member, HomC. Overall, we identified and genotyped three homC variants: homCS, homCL, and homCM, in both populations. Similar to other polymorphic genes, the KH group showed less overall diversity, with 97.5% of strains harboring homCL. In contrast, a more heterogeneous profile was observed in strains derived from an American population; we found nearly equal distribution of homCS and homCL. Further analysis of the AH group identified associations between homC polymorphism and bab genotype; in AH strains, there was a significant association between homCL and carriage of babA at locus A. Since babA is an important virulence factor for the development of severe gastric disease, these data may suggest that homC polymorphism plays a role in H. pylori pathogenesis.

The effect of flufenamic acid, an activator of TRPC6, on periodontal tissue of periodontitis mice

Aeri Kim,Aeryun Kim,Yu-Mi Yang,Yun-Jung Yoo,Eun-Jung Bak 한국실험동물학회 2020 한국실험동물학회 학술발표대회 논문집 Vol.2020 No.2

Role of bacterial γ-glutamyltranspeptidase as a novel virulence factor in bone-resorbing pathogenesis

Jinmoon Kim,장성일,Aeryun Kim,Hanfu Su,Niluka Gunawardhana,Yeong-Eui Jeon,Eun Jung Bak,김지혜,차정헌 한국미생물학회 2016 The journal of microbiology Vol.54 No.5

Mammalian γ-glutamyltranspeptidase (GGT) has been identified as a bone-resorbing factor. Since GGT of Bacillus subtilis exhibits similarity in their primary structure and enzymatic characteristics with mammalian GGTs, the bone-resorbing activity of bacterial GGT was examined in this study. Osteoclastogenesis was performed in a co-culture system of mouse calvaria-derived osteoblasts and bone marrow cells. A conditioned medium from GGT-overproducing B. subtilis culture showed significantly higher activity of osteoclast formation than a conditioned medium from wild-type B. subtilis culture. Recombinant GGT (rGGT) of wild-type B. subtilis and an enzymatic activity-defected rGGT of B. subtilis 2288 mutant were expressed in Escherichia coli and purified using His tag. Both purified rGGTs induced similar levels of osteoclastogenesis, suggesting that B. subtilis GGT possesses virulent boneresorbing activity and its activity is probably independent of its enzymatic activity. Furthermore, a recombinant protein of B. subtilis GGT heavy subunit (Bs rGGT/H) showed strong activity of osteoclastogenesis while the light subunit failed to show strong activity, suggesting that the bone-resorbing activity is mainly located at the heavy subunit. More importantly, the GGT enzymatic activity may not be required for this virulence activity since the light subunit contains the catalytic pocket. In addition, B. subtilis rGGT stimulated mRNA expressions of receptor activator of nuclear factor kappa-B ligand (RANKL) and cyclooxygenase-2 (COX-2), while an osteoprotegerin inhibited the osteoclast formation induced by Bs rGGT/H. This is the first demonstration that bacterial GGT itself is sufficient to act as a bone-resorbing virulence factor via RANKL-dependent pathway. Therefore, it can be hypothesized that GGT of periodontopathic bacteria may play an important role as a virulence factor in bone destruction.

Expression of TRP calcium channels in human periodontal ligament cells and periodontitis mice

Ae Ri Kim,Aeryun Kim,Yu-Mi Yang,Yun-Jung Yoo,Eun-Jung Bak 한국실험동물학회 2019 한국실험동물학회 학술발표대회 논문집 Vol.2019 No.1

CagL polymorphisms between East Asian and Western Helicobacter pylori are associated with different abilities to induce IL-8 secretion

최윤희,Lai Jing,Kim Myeong-A,Kim Aeryun,Kim Jinmoon,Su Hanfu,Ge Linhu,Cha Jeong-Heon 한국미생물학회 2021 The journal of microbiology Vol.59 No.8

Helicobacter pylori colonizes human gastric mucosa. Its infection is associated with gastric diseases including gastric cancer. CagA is one of the most important toxins produced by H. pylori. It is related to gastric cancer which can be injected into host cells via a type IV secretion system (T4SS). CagL is a structural component of T4SS apparatus, which triggers host cell signaling pathway. It has been reported that CagL polymorphisms may influence the severity of disease development. To explore the contribution of CagL polymorphisms between East Asian and Western H. pylori in pathogenesis, cagL gene in G27 H. pylori was swapped by K74 cagL which is identical to East Asian CagL consensus sequence and by Western 26695 H. pylori, resulting in G27ΔcagL/cagLK74 and G27ΔcagL/cagL26695, respectively. Intriguingly, G27ΔcagL/ cagLK74 showed significantly less ability of IL-8 induction than G27ΔcagL/cagL26695 while displayed similar abilities of CagA phosphorylation, and cell elongation. Taken together, this study suggests that the CagL polymorphism may influence IL-8 induction, and K74 CagL has less ability to induce IL-8 secretion than G27 or 26695 CagL. Further research should address how the different capabilities of IL-8 induction between intraspecies-CagL are associated with the large differences of the incidence of gastric cancer between East Asian and Western countries.

한국형 재활환자분류체계 버전 1.0 개발

황수진 ( Soojin Hwang ),김애련 ( Aeryun Kim ),문선혜 ( Sunhye Moon ),김지희 ( Jihee Kim ),김진휘 ( Jinhwi Kim ),하영혜 ( Younghea Ha ),양옥영 ( Okyoung Yang ) 한국보건행정학회 2016 보건행정학회지 Vol.26 No.4

Background: Rehabilitations in subacute phase are different from acute treatments regarding the characteristics and required resource consumption of the treatments. Lack of accuracy and validity of the Korean Diagnosis Related Group and Korean Out-Patient Group for the acute patients as the case-mix and payment tool for rehabilitation inpatients have been problematic issues. The objective of the study was to develop the Korean Rehabilitation Patient Group (KRPG) reflecting the characteristics of rehabilitation inpatients. Methods: As a retrospective medical record survey regarding rehabilitation inpatients, 4,207 episodes were collected through 42 hospitals. Considering the opinions of clinical experts and the decision-tree analysis, the variables for the KRPG system demonstrating the characteristics of rehabilitation inpatients were derived, and the splitting standards of the relevant variables were also set. Using the derived variables, we have drawn the rehabilitation inpatient classification model reflecting the clinical situation of Korea. The performance evaluation was conducted on the KRPG system. Results: The KRPG was targeted at the inpatients with brain or spinal cord injury. The etiologic disease, functional status (cognitive function, activity of daily living, muscle strength, spasticity, level and grade of spinal cord injury), and the patient`s age were the variables in the rehabilitation patients. The algorithm of KRPG system after applying the derived variables and total 204 rehabilitation patient groups were developed. The KRPG explained 11.8% of variance in charge for rehabilitation inpatients. It also explained 13.8% of variance in length of stay for them. Conclusion: The KRPG version 1.0 reflecting the clinical characteristics of rehabilitation inpatients was classified as 204 groups.

Effect of Areca Nut on Helicobacter pylori-Induced Gastric Diseases in Mice

( Jinwook Lee ),( Niluka D Gunawardhana ),( Sungil Jang ),( Yun Hui Choi ),( Rasika P Illeperuma ),( Aeryun Kim ),( Hanfu Su ),( Youngmin A Hong ),( Ji-hye Kim ),( Jinmoon Kim ),( Da-woon Jung ),( In- 한국미생물 · 생명공학회 2016 Journal of microbiology and biotechnology Vol.26 No.10

Areca nut (AN) chewing is a habit in many countries in Central, Southern, and Southeast Asia. It is strongly associated with the occurrence of oral, pharyngeal, and esophageal cancer as well as systemic inflammation. However, the association between AN intake and the development of gastric lesions has not yet been identified. The aim of this study was to investigate the effect of AN on gastric diseases using a mouse model for Helicobacter pylori infection. We studied four groups of mice: those fed a normal diet (ND), those fed a diet containing 2.5% AN (AD), those fed ND and infected with H. pylori PMSS1 strain (ND/HP), and those fed AD and infected with H. pylori PMSS1 strain (AD/HP). Food intake and body weight were monitored weekly during the experiments. At 10 weeks, the mice were sacrificed, and the stomach weight, H. pylori colonization, and gastric inflammation were evaluated. The stomach weight had increased significantly in the ND/HP and AD/HP groups along with increases in H. pylori colonization; however, there was no significant difference between these two groups with respect to stomach weight and colonization. On histological grading, mononuclear cell infiltration was severer in the AD/HP group than in the ND/HP group. These data suggest that chronic gastric inflammation was aggravated by AN treatment in the mice with H. pyloriinduced gastric lesions. Furthermore, as previously suggested, this animal model is useful to determine the effect of potential carcinogens on gastric lesions induced by H. pylori infection.