• Tissue Engineering and Regenerative Medicine
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• v.15 no.6
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• pp.771-779
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• 2018

BACKGROUND: Mesenchymal stromal cells (MSCs) are multipotent stem cells that can differentiate into several cell types. In addition, many studies have shown that MSCs modulate the immune response. However, little information is currently available regarding the maintenance of immunomodulatory characteristics of MSCs through passages. Therefore, we investigated and compared cytokine and gene expression levels from adipose (AD) and bone marrow (BM)-derived MSCs relevant to immune modulation from early to late passages. METHODS: MSC immunophenotype, growth characteristics, cytokine expressions, and gene expressions were analyzed. RESULTS: AD-MSCs and BM-MSCs had similar cell morphologies and surface marker expressions from passage 4 to passage 10. Cytokines secreted by AD-MSCs and BM-MSCs were similar from early to late passages. AD-MSCs and BM-MSCs showed similar immunomodulatory properties in terms of cytokine secretion levels. However, the gene expressions of tumor necrosis factor-stimulated gene (TSG)-6 and human leukocyte antigen (HLA)-G were decreased and gene expressions of galectin-1 and -3 were increased in both AD- and BM-MSCs with repeated passages. CONCLUSION: Our study showed that the immunophenotype and expression of immunomodulation-related cytokines of AD-MSCs and BM-MSCs immunomodulation through the passages were not significantly different, even though the gene expressions of both MSCs were different.

• Parasites, Hosts and Diseases
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• v.59 no.1
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• pp.9-14
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• 2021

Toxoplasma gondii seroprevalence have been rapidly increasing in some parts of Korea. We analyzed prevalence of anti-Toxoplasma gondii antibodies, using a rapid diagnostic test (RDT), in the sera of 552 residents in Ganghwagun, 661 ones in Cheorwon-gun, and 305 ones in Goseong-gun, Korea in 2019. IgG/IgM RDT mounted with recombinant fragment of major surface antigen (SAG1), glutathione-S-transferase-linker-SAG1A, were applied to the sera. IgG seroprevalence was 28.1% in Ganghwa-gun, 19.5% in Cheorwon-gun and 35.7% in Goseong-gun. Odds ratios comparing Cheorwon vs Ganghwa was 0.63 (P=0.001) and Goesong versus Ganghwa was 1.47 (P=0.01) adjusting age and sex. Goseong had highest seroprevalence among the 3 counties both in crude rates and logistic regression. Although Cheorwon and Goseong are adjacent to the demilitarized zone (DMZ) in Korea, seroprevalence rate was much higher in Goseong. Further investigation on other DMZ-closed areas is necessary whether they have high prevalence rates compared to the other areas. T. gondii prevalence in Korea is still persists; proper health policy should be established.

• 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.

• Hanyang Medical Reviews
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• v.33 no.1
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• pp.10-16
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• 2013

Follicular helper T cells (Tfh) play a significant role in providing T cell help to B cells during the germinal center reaction, where somatic hypermutation, affinity maturation, isotype class switching, and the differentiation of memory B cells and long-lived plasma cells occur. Antigen-specific T cells with IL-6 and IL-21 upregulate CXCR5, which is required for the migration of T cells into B cell follicles, where these T cells mature into Tfh. The surface markers including PD-1, ICOS, and CD40L play a significant role in providing T cell help to B cells. The upregulation of transcription factor Bcl-6 induces the expression of CXCR5, which is an important factor for Tfh differentiation, by inhibiting the expression of other lineage-specific transcription factors such as T-bet, GATA3, and RORγt. Surprisingly, recent evidence suggests that CD4 T cells already committed to Th1, Th2, and Th17 cells obtain flexibility in their differentiation programs by downregulating T-bet, GATA3, and RORγt, upregulating Bcl-6 and thus convert into Tfh. Limiting the numbers of Tfh within germinal centers is important in the regulation of the autoantibody production that is central to autoimmune diseases. Recently, it was revealed that the germinal center reaction and the size of the Tfh population are also regulated by thymus-derived follicular regulatory T cells (Tfr) expressing CXCR5 and Foxp3. Dysregulation of Tfh appears to be a pathogenic cause of autoimmune disease suggesting that tight regulation of Tfh and germinal center reaction by Tfr is essential for maintaining immune tolerance. Therefore, the balance between Tfh and Tfr appears to be a critical peripheral tolerance mechanism that can inhibit autoimmune disorders.

• Journal of Preventive Medicine and Public Health
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• v.30 no.1 s.56
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• pp.103-128
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• 1997

The object of this study is to evaluate the possibility of chemical-induced liver disorder among workers exposed to various chemicals and to classify the the liver function abnormalities by causes and to analyse the risk factors for each liver disorders. A cross-sectional study including questionnaire survey, physical examination, laboratory tests and ultrasonography of liver was conducted on 1,126 workers, 459 workers in a coal chemical plant(company A) and 667 workers in an insulation material manufacturing factory(company B). An industrial hygienist reviewed the chemicals used in both companies and evaluated the work environments to classify the workers by chemical exposure semiquantitatively. The results are as follows: 1. Of 459 workers in company A, 83 workers(18.1%) are classified as nonexposed, group 163(35,5%) as short-term exposure group, 155(33.8%) as intermediately exposed group and 58(12.6%) as long-term exposed group bared on the mean daily exposure to hepatotoxic chemicals evaluated by an industrial hygienist. Of 667 workers in company B, 484(72.6%) workers were classified as nonexposed and 183(35.5%) as exposed group. 2. Workers with SGOT level higher than 40 IU/l were (10.0%) in company A and 77(11.5%) in company 3, and those with SGPT level higher than 35 IU/l were 118(25.7%) in company A and 198(29.7%) in company B. The differences were not significant between companies and between exposure groups(p>0.05). Workers with $\gamma-GT$ level higher than 62 IU/l were 29(6.3%) in company A and 77(11.5%) in company B (p<0.01). The difference between exposure groups was not significant(p>0.05) within companies. Workers with liver function abnormalities(defined as SGOT higher than 40 IU/l or SGPT higher than 35 IU/l) were 338(30.0%) among 1,126 workers. Of 338 workers with live. function abnormalities 139(12.3%) had fatty liver by ultrasonography, 79(7.0%) had alcoholic liver(defined as workers with liver function abnormalities with weekly alcohol consumption greater than 280 g for more than 5 years), 54(4.8%) had hepatitis B, 12(1.1%) had hepatitis C and the other 114(33.7%) was not otherwise classified. Prevalences of alcoholic liver and fatty liver were significantly lower in company A(prevalence ratio 0.24 for alcoholic liver, p<0.001, prevalence ratio 0.76 for fatty liver, p<0.05) but prevalences of liver disorders between exposure groups within companies were not significant(p>0.05). 3. Summary prevalence ratios(SPR) of live. function abnormalities, fatty live. and other liver disorders, adjusted by age and company were not significantly higher in exposed group in any chemicals(p>0.05) but in some chemicals, SPRs were significantly lower. 4. On simple analysis of risk factors for liver function abnormalities, prevalence odds ratio(POR) of those with age between 30 and 39 was 1.54(p<0.01) and those with age ever 40 was 1.51(p<0.01). POR of those with histories of liver disorders and general anesthesia was 1.77(p<0.001) and 4.02 for those with overweight and 6.23 for those with obesity, defined by body mass index(p<0.001). 5. On logistic regression analysis, risk factors of liver function abnormality were fatty liver(POR 2.92 for grade 1, 12.15 for grade 2), presence of hepatitis B surface antigen(POR 3.62) and obesity(POR 5.38 for overweight and 16.52 for obesity). Presence of hepatitis B surface antigen(POR 0.18) was the only preventive facto. of fatty live. Company(POR 0.30) and obesity(POR 2.49 for overweight, 4.52 for obesity) were related to the alcoholic live. Obesity(POR 2.94 for overweight) was the only significant risk factor of hepatitis B and there was no significant risk factor for liver function abnormality not otherwise classified. It is concluded that the evidence of liver disorder related with chemical exposure is not evident in these factories. It is also postulated that fatty liver and alcoholic liver is most common causes of liver function abnormalities among workers and effort for weight control and improvement of life style should be done.

• Biomedical Science Letters
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• v.2 no.1
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• pp.1-12
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• 1996

Antigenic components reacting with IgE and IgG antibodies were localized in muscular layer of adult and of larva, sparganum. But the antigenic components inducing IgG were localized at tegument and parenchyma in addition to muscular layer in adult and sparganum. Also in sparganum, the surface of calcareous corpuscles of parenchyma showed immunoreactivity to IgG antibody. However antigenic components inducing IgE antibody were not localized in tegument and parenchyma, but in adult worm, we observed the immunopositive reaction at the lining of vitelline follicles in mature proglottis and on surface of egg shell within uterus of graved proglottis. By the method of immunogold-labelling, we observed the location of antigenic particles in tegument of sparganum. The density of antigenic particles inducing IgG was higher than that of antigen particles inducing IgE in syncytial tegument, tegument cells. A total of 43 and 36 protein bands were resolved from crude extracts of adult and sparganum, respectively, by SDS-PAGE. 34 bands from crude extracts of adult and larva were migrated to same positions. By EITB, 21 bands of 44 bands in adult were recognized with IgG antibody, and also 21 bands of 36 bands in sparganum. 13 bands of them were common antigenic components both in the adult worm and sparganum. Because 19 bands of 44 bands in adult worm were reacted with IgE antibody, they were IgE antigenic component. In sparganum, 13 bands were IgE antigenic components. 9 bands of them were common antigenic component inducing IgE antibody in both a-dult and sparganum. 3 bands of antigenic component recognized by IgE and IgG antibody were nonspecific antigen in both adult and sparganum of Spirometra erinacei.

• Journal of Food Hygiene and Safety
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• v.26 no.4
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• pp.424-434
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• 2011

The increase in the consumption of herb medicines have made their use a public health problem due to the potential fungal contamination and the risk of the presence of my cot ox ins. 360 samples of herb medicines were evaluated for the aflatoxin contamination. The natural occurrence of aflatoxins in these samples were determined using immunoaffinity column clean up and high performance liquid chromatography (HPLC) with post-column derivatization. For samples analyzed, mean levels (incidence) of AFB1, AFB2, AFG1 and AFG2 in positive samples were $1.4\;{\mu}g/kg$(46.4%), $0.4\;{\mu}g/kg$(25.4%), $1.1\;{\mu}g/kg$(37.8%) and $0.9\;{\mu}g/kg$(24.3%), respectively. Recoveries of the full analytical procedure were 71.7~99.7% for AFB1, 88.1~99.2% for AFB2, 82.8~95.5% for AFG1 and 77.9~90.0% for AFG2. The excess cancer risk estimated using the cancer potency of aflatoxin B1 (7 $(mg/kg/day)^{-1}$ for $HBsAg^-$ and 230 $(mg/kg/day)^{-1}$ for $HBsAg^+$) were $1.30{\times}10^{-5}{\sim}1.22{\times}10^{-7}$ for hepatits B surface antigen negative ($HBsAg^-$) and $3.31{\times}10^{-4}{\sim}3.12{\times}10^{-6}$ for hepatits B surface antigen positive ($HBsAg^+$) respectively. In conclusion, although the contamination levels of samples used in the study were low, further actions are also required to undertake a program of herbal surveys in order to access mycotoxin contamination overall so that the safety of public will be protected.

• Korean Journal of Veterinary Research
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• v.25 no.1
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• pp.7-17
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• 1985

Many investigators have been pursuing various attempts so far to produce hepatitis B surface antigen(HBsAg) vaccines using the techniques such as isolation from plasma of chronic HBsAg carrier, recombinant DNA technique or preparation of synthetic peptides specific for immunogenic determinants. Hepatitis B virus can not grow on any cell lines by the tissue culture technique at the present time. The plasma of chronic HBsAg carrier is expensive and its source is limited. The HBsAg from the recombinant DNA technique gave still very low yield. Another approach, therefore, has been initiated to develop a synthetic hepatitis B virus vaccine. The possible use of several distinct synthetic vaccines in prophylaxis can be facilitated by availability of full synthetic immunogens. Peptides synthesized for potential application as antiviral vaccines have been mostly tested in the form of conjugates with carrier proteins, although the free synthetic peptide can be immunogenic. To understand basic knowledges on the antigenicity and immunogenicity of a synthetic peptide specific for major immunogenic determinant of HBsAg, a nonapeptide, $H_2N^{139}Cys-Thr-Lys-Pro-Thr-Asp-Gly-^{146}Asn-Aba$ COOH, which corresponds to HBsAg amino acid residues 139 to 147, was synthesized by the Merrifield's solid-phase method with a slight modification. The antigenicity and immunogenicity of this specific synthetic peptide were examined comparing with purified plasma-derived natural HBsAg. The results obtained are as follows; 1. The peptide synthesized showed the identical amino acid composition to the theoretical value. The degree of purification and molecular weight were acertained by methods of high performance liquid chromatography and mass spectrometry. 2. Using m-maleimidobenzoyl-N-hydroxysuccinimide ester as a conjugating agent, the synthetic peptide was conjugated to rabbit albumin and ${\gamma}$-globulin, tetanus and diphtheria toxoids, and keyhole limpet hemocyanin. Their conjugation yields were 8.3, 9.5, 15.8, 13.5, and 11.2%, respectively. 3. The natural HBsAg was purified from plasma of chronic HBsAg carrier. By the electron microscopic observation of the purified natural HBsAg preparation, no Dane particles were observed and the preparation showed negative DNA polymerase activity. 4. Antigenicity of the synthetic peptide and the plasma-derived natural HBsAg was determined by competition radioimmunoassay using $^{125}I$-natural HBsAg. Their 50% inhibitions appeared as $90{\mu}g/ml$ and $0.12{\mu}g/ml$ for the synthetic peptide and the natural HBsAg, respectively. This indicates that the former was about 750-fold less antigenic than the latter. 5. Immunogenicity of the synthetic peptide was determined by administering the peptide-carrier conjugates into rabbits with and without Freund's complete adjuvant. Regardless the carrier proteins and adjuvant, positive immune responses to the synthetic peptide were observed. The higher antibody titers, however, were shown in the groups administered with Freund's complete adjuvant. 6. Immunizing dose 50% in mice of the various peptide-carrier conjugates was 5.47, 6.00, 65.16, 31.25 and $13.03{\mu}g/dose$ for rabbit albumin and ${\gamma}$-globulin, tetanus and diphtheria toxoids, and keyhole limpet hemocyanin, respectively, while the natural HBsAg showed $0.65{\mu}g/dose$. 7. It was postulated that homologous proteins prefer to heterologous ones as the carriers.

• The Korean Journal of Blood Transfusion
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• v.29 no.3
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• pp.301-309
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• 2018

Background: If donors who were deferred due to the reactivity or grey zone in HBV surface antigen (HBsAg) assay want to donate blood again, they need to pass reentry tests. On the other hand, approximately half of the donors who are subject to the reentry tests cannot be reentered. This study examined the association between the sample to cutoff (S/Co) value of the HBsAg assay and the final results of the reentry test. Methods: This study analyzed the S/Co values of the HBsAg assay and the final results of the reentry tests for the 3,947 donors from January 2008 to December 2017 using the database of Blood Information Management System of the Korean Red Cross. Results: 1,767 donors (44.8%) were not reentered among 3,947 deferred donors. Among 1,585 donors showing ${\geq}10$ of the S/Co value in the HBsAg screening test, 1,542 donors (97.3%) were not reentered. The additional reentry tests were performed on 120 donors who were not reentered in the first reentry test; 98 donors (81.7%) were still not reentered. Overall, 4.6% of the donors showing a grey zone in the HBsAg assay were not reentered. Conclusion: The reentry test needs to be restricted for the deferred donors showing a more than 10 S/Co value. The application of the grey zone of current HBsAg assay will need to be continued to enhance the HBV-related blood safety.

• The Journal of the Korean Society for Microbiology
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• v.15 no.1
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• pp.9-17
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• 1980

In the ecology and epidemiologic studies on various serotypes of atypical mycobacteria(AM), Schaefer's bacterial agglutination test(BA) provided the basis of the serologic procedures. Recently, attempts have been made to modify and to simplify the Schaefer's BA such as a slide agglutination test(Engel & Beerwald, 1970), a "simplified" BA(Reznikov & Leggo, 1972), an agglutination inhibition test(Richards & Eacret, 1972) and "micromethod"(Thoen et al., 1975). The BA, however, was not widely applied as a routine laboratory test mainly because it requires much times and labors to perform and partley because it is not applicable to hydrophobic strains either often encountered in the isolation of AM in the clinical bacteriology or stock strains maintained in the laboratory. On the contrary, fluorescent antibody technique with mycobacteria may have advantages over the BA because it is far more simpler in serologic procedures and is applicable to all strains of mycobacteria regardless of smooth or rough types of cultures. At the present, it is well known that the type-specific antigens are lacking on the surface of rough type of AM compared to that on smooth type of strain, but the antigenicity on the surface of the hydrophobic strains of AM which resulted from a series of subculture and the strain in the laboratory for 3 to 6 months has not been clarified. In this study, an attempt to serotype the hydrophobic strains of M. scrofulaceum serotype 41, 42 and 43 by fluorescent anti-complement(FAC) technique was made. The FAC technique with mycobacteria was also described in detail. In the summary, the complement fixing antibody titres of reference sera to smooth types of homologous serotype was highest, but the antibody titres of reference sera to hydrophobic strains of serotypes, 41, 42 and 43 gave two-to 8-folds lower than those to smooth type of strains. Although the sensitivity of type-specific antigens on the hydrophobic strains to reference sera was much lower, using the two units of reference sera determined by titration with hydrophobic strains, three serotypes, i. e., 41, 42 and 43 were specifically differentiated one another by FAC technique. This result indicated that the hydrophobic strains which were maintained in the laboratory at least for 6 months still retain type-specific antigen detectable by FAC technique.