• Journal of Microbiology and Biotechnology
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• v.33 no.9
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• pp.1206-1212
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• 2023

The Wnt/β-catenin pathway plays essential roles in regulating various cellular behaviors, including proliferation, survival, and differentiation [1-3]. The intracellular β-catenin level, which is regulated by a proteasomal degradation pathway, is critical to Wnt/β-catenin pathway control [4]. Normally, casein kinase 1 (CK1) and glycogen synthase kinase-3β (GSK-3β), which form a complex with the scaffolding protein Axin and the tumor suppressor protein adenomatous polyposis coli (APC), phosphorylate β-catenin at Ser45, Thr41, Ser37, and Ser33 [5, 6]. Phosphorylated β-catenin is ubiquitinated by the β-transducin repeat-containing protein (β-TrCP), an F-box E3 ubiquitin ligase complex, and ubiquitinated β-catenin is degraded via a proteasome pathway [7, 8]. Colorectal cancer is a significant cause of cancer-related deaths worldwide. Abnormal up-regulation of the Wnt/β-catenin pathway is a major pathological event in intestinal epithelial cells during human colorectal cancer oncogenesis [9]. Genetic mutations in the APC gene are observed in familial adenomatous polyposis coli (FAP) and sporadic colorectal cancers [10]. In addition, mutations in the N-terminal phosphorylation motif of the β-catenin gene were found in patients with colorectal cancer [11]. These mutations cause β-catenin to accumulate in the nucleus, where it forms complexes with transcription factors of the T-cell factor/lymphocyte enhancer factor (TCF/LEF) family to stimulate the expression of β-catenin responsive genes, such as c-Myc and cyclin D1, which leads to colorectal tumorigenesis [12-14]. Therefore, downregulating β-catenin response transcription (CRT) is a potential strategy for preventing and treating colorectal cancer. Plant cytokinins are N⁶-substituted purine derivatives; they promote cell division in plants and regulate developmental pathways. Natural cytokinins are classified as isoprenoid (isopentenyladenine, zeatin, and dihydrozeatin), aromatic (benzyladenine, topolin, and methoxytopolin), or furfural (kinetin and kinetin riboside), depending on their structure [15, 16]. Kinetin riboside was identified in coconut water and is a naturally produced cytokinin that induces apoptosis and exhibits antiproliferative activity in several human cancer cell lines [17]. However, little attention has been paid to kinetin riboside's mode of action. In this study, we show that kinetin riboside exerts its cytotoxic activity against colon cancer cells by suppressing the Wnt/β-catenin pathway and promoting intracellular β-catenin degradation.

• IMMUNE NETWORK
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• v.21 no.5
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• pp.33.1-33.19
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• 2021

IL-1β plays critical roles in the priming and effector phases of immune responses such as the differentiation, commitment, and memory formation of T cells. In this context, several reports have suggested that the IL-1β signal is crucial for CTL-mediated immune responses to viral infections and tumors. However, little is known regarding whether IL-1β acts directly on CD8⁺ T cells and what the molecular mechanisms underlying expression of IL-1 receptors (IL-1Rs) on CD8⁺ T cells and features of IL-1R⁺ CD8⁺ T cells are. Here, we provide evidence that the expression of IL-1R type I (IL-1RI), the functional receptor of IL-1β, is preferentially induced by IL-21 on TCR-stimulated CD8⁺ T cells. Further, IL-1β enhances the effector function of CD8⁺ T cells expressing IL-21-induced IL-1RI by increasing cytokine production and release of cytotoxic granules containing granzyme B. The IL-21-IL-1RI-IL-1β axis is involved in an augmented effector function through regulation of transcription factors BATF, Blimp-1, and IRF4. Moreover, this axis confers a unique effector function to CD8⁺ T cells compared to conventional type 1 cytotoxic T cells differentiated with IL-12. Chemical inhibitor and immunoprecipitation assay demonstrated that IL-21 induces a unique pattern of STAT activation with the formation of both STAT1:STAT3 and STAT3:STAT5 heterodimers, which are critical for the induction of IL-1RI on TCR-stimulated CD8⁺ T cells. Taken together, we propose that induction of a novel subset of IL-1RI-expressing CD8⁺ T cells by IL-21 may be beneficial to the protective immune response against viral infections and is therefore important to consider for vaccine design.

• Tuberculosis and Respiratory Diseases
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• v.49 no.2
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• pp.149-161
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• 2000

Background : Residual pleural thickening (RPT) develops in about 50% of tuberculous pleurisy ($PL_{TB}$). Some reports have suggested that elevated TNF-$\alpha$ and impaired fibrinolysis could be the cause of RPT, but until now, the mechanism and predictors of RPT have not been well known. TGF-$\beta$ has been known to promote fibrogenesis and is increased in tuberculous pleural fluid (PF). $PL_{TB}$ and malignant pleurisy ($PL_{MAL}$) manifest lymphocyte-dominant exudative pleural effusion, and it has clinical implications in the differentiation of the two diseases based on the findings of pleural effusion. We performed this study to compare pleural fluid TNF-$\alpha$ TGF-$\beta$, and fibrinolytic parameters between $PL_{TB}$ and $PL_{MAL}$, and to find the predictors of RPT in $PL_{TB}$. Methods : Thirty-five $PL_{TB}$ and 14 $PL_{MAL}$ patients who were admitted to the Asan Medical Center from February 1997 to August 1999 were enrolled. All $PL_{TB}$ patients were prescribed a primary, short-course, anti-tuberculosis regimen. INF-$\alpha$ tissue plasminogen activator (tPA), plasminogen activator inhibitor 1 (PAI-1), plasminogen, $\alpha$2-antiplasmin, and D-dimer were measured in both PF and PB. TGF-$\beta$was measured only in PF. Clinical characteristics, TNF-$\alpha$ TGF-$\beta$ and fibrinolytic parameters were compared between patients with RPT less than 2 mm and patients with more than 2 mm of the thirty patients who completed the anti-tuberculosis treatment. Results : The levels of TNF-$\alpha$ tPA, PAI-1, plasminogen, $\alpha$2-antiplasmin, and D-dimer in PF were higher than those in peripheral blood (PB) in $PL_{TB}$, whereas only plasminogen, $\alpha$2-antiplasmin, and D-dimer were higher in PF than in PB in $PL_{MAL}$. Pleural fluid TNF-$\alpha$ TGF-$\beta$, PAI-1, plasminogen, $\alpha$2-antiplasmin were increased in $PL_{TB}$ compared with $PL_{MAL}$, but these factors did not show any further advantages over ADA in differentiation between $PL_{TB}$ and $PL_{MAL}$. TNF-$\alpha$ TGF-$\beta$ and fibrinolytic parameters did not show any differences between patients with RPT less than 2 mm and patients with RPT more than 2 mm. Conclusion : Our data suggest that TNF-$\alpha$, TGF-$\beta$ and fibrinolytic parameters may play some role for the development of RPT in $PL_{TB}$, but they failed to predict the occurrence of RPT in $PL_{TB}$. Also these parameters did not seem to have any advantages over ADA in differentiating between two diseases.

• Tuberculosis and Respiratory Diseases
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• v.52 no.6
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• pp.608-615
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• 2002

Background : ADA is an enzyme found in most cells, and is involved in purine metabolism, but its chief role concerns the proliferation and differentiation of lymphocytes, especially T-lymphocytes. For that reason ADA has been looked on as a marker of cell-mediate immunity, which is the key mechanism of the tuberculous pleural effusion. Thus, the pleural fluid ADA activity is increased in the tuberculous pleural effusion. Age associated immune decline is characterized by decreases in both B and T-lymphocyte function and the former may be largely a result of the latter. Therefore, the pleural fluid ADA activity would be lower in old rather than in young, patients with tuberculous pleural effusion. We studied the relationship between age, and pleural fluid ADA activity, in patients with tuberculous pleural effusion. Materials and Methods : In the 46 patients with tuberculous pleural effusion enroll in this study, the pleural fluid ADA activities were measured by means of an automated kinetic method. Results : The mean age of the patients was $53.0{\pm}22.0$ years, with a male to female ratio of 30:16. The patients were divided into two groups, young patients, regarded as < 65 and old regarded as ${\geq}65$ years with 28 and 18 patients, respectively. The pleural fluid ADA activity in both groups show significant differences : $99.4{\pm}22.6$ IU/L(young patients) Vs. $75.8{\pm}30.9$ IU/L(old patients)(p<0.05), but a negative correlation with age (r=-0.311, p<0.05). Conclusion : Although pleural fluid ADA activity was not adequately increased, tuberculous pleural effusion, in older patients, would have to be considered clinically suspicious tuberculous pleural effusion.

• Tuberculosis and Respiratory Diseases
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• v.41 no.2
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• pp.135-143
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• 1994

Background: The cell mediated immunity has an important role in the pathogenesis of tuberculosis. sIL-2R has been known as a sensitive marker of T lymphocyte activation Elevated serum levels of sIL-2R have been found in patients with lymphoproliferative disorders, organ transplantation, autoimmune diseases, and various granulomatous diseases. Elevated levels of sIL-2R have been also found in the serum and pleural fluid of the patients with tuberculosis. To evaluate the diagnostic value of sIL-2R in the differentiation of tuberculous pleurisy and nontuberculous pleurisy. We measured the level of sIL-2R in the sera and pleural fluids of 12 patients with tuberculous pleurisy and 32 patients with nontuberculous pleurisy. Method: Samples of pleural fluid and serum were centrifuged at 2500 rpm for 10 min to remove cell pellets. Soluble IL-2R was measured with a sandwitch enzyme immunoassay using the Cellfree(r) Interleukin-2 Receptor Test kit(T-cell science,Inc. Cambridge, MA). Results: The results obtained were as follows: 1) The sIL-2R level in pleural fluid of the patients with tuberculous pleurisy was higher than that of patients with nontuberculous pleurisy(P<0.005). 2) When the sIL-2R level above 5,000 u/ml in pleural fluid was used as the cut-off value to diagnose tuberculous pleurisy, it had a sensitivity of 84.6% and a specificity of 90.9%. 3) The sIL-2R level in the sera of the patients with tuberculous pleurisy was higher than that of patients with bacterial pleural effusions and normal control group(P<0.05) and there was no difference of levels compared with malignant pleural effusions and transudative pleural effusions(P>0.05). 4) In patients with tuberculous pleurisy, the mean concentration of sIL-2R in pleural fluid was higher than that in serum(P<0.005). Conclusion: These findings suggest that the measurement of elevated levels of pleural fluid sIL-2R in tuberculous pleurisy may be useful in the differential diagnosis between patients with tuberculous pleurisy and nontuberculous pleurisy.

• Korean Journal of Microbiology
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• v.35 no.2
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• pp.164-168
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• 1999

TGF-$\beta$3 is among five TGF-$\beta$ isolorms and shows 80% sequence identity to TGF-$\beta$I, a prototype of TGF--$\beta$. It has been reported that TGF-$\beta$I, particularly in the presence of IL-2 or L-5, increases the pmduction of IgA and IgG2b isoiypes by LPS-actwated murine B cells. We examined the effect of TGF-P3 on Ig synlhesis by B cells from different lymphoid origins. IgA induction by TGP-$\beta$3 was mardnal in LPS-activated spleen B cell culture, while 1gA production was markedly enhanced in the culture shulated with TGF-$\beta$P3 and L-5. In addition, number of IgA secreting cells was increased by TGF-$\beta$P3. Under the same conditions, TGP-$\beta$3 alone was enough to increase IgG2b production but IgM and 1gGl. Sirmlar patiem of IgA and IgGZb enbancement by TGF-$\beta$3 and L-5 was observed in the cullures of mesenteric lymph node B cells. Thus, overall effect of TGF-$\beta$3 on Ig synthesis was quite similar to that of TGF-$\beta$I. Nonetheless, it remains to be underslood whether TGF-$\beta$3 is an important modulator in B cell differentiation since regulation of TGF-$\beta$3 expression is considered to differ from that of TGF-$\beta$I

• Tuberculosis and Respiratory Diseases
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• v.38 no.1
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• pp.16-24
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• 1991

Adenosine deaminase (ADA) is an enzyme which is essential for the differentiation of lymphoid cells, especially T-cells and ADA plays a role in the maturation of monocyte to macrophage. Therefore ADA levels are related to stimulation of cellular immunity. We have investigated the measurement of ADA activity in bronchoalveolar lavage fluid of the patients with active and inactive pulmonary tuberculosis and control group. The results obtained are as follows: 1) The ADA activity and corrected ADA activity from the BAL fluid in active tuberculosis group (Total Lavage ADA; $18.4{\pm}22.5\;mU$, Total Lavage ADA/Albumin; $2.45{\pm}1.61\;mU/mg$) were increased when compared with those in inactive tuberculosis (TL-ADA; $5.8{\pm}2.5\;mU$, TL-ADA/Alb; $1.83{\pm}O.53\;mU/mg$) and control (TL-ADA; $6.6{\pm}4.3\;mU$, TL-ADA/Alb; $1.62{\pm}0.60\;mU/mg$) groups. 2) The ADA activity and lavage ADA/serum ADA activity ratio in BAL fluid from the lesion site (TL-ADA; $42.9{\pm}42.3\;mU$, L-ADA/S-ADA; $0.53{\pm}0.32$) were increased when compared with those from the non-lesion site (TL-ADA; $12.5{\pm}11.2\;mU$, L-ADA/S-ADA; $0.29{\pm}0.12$)and normal side (TL-ADA; $12.7{\pm}11.0\;mU$, L-ADA/S-ADA; $0.34{\pm}0.27$) in active tuberculosis group. 3) The ADA activity in BAL fluid from far advanced group (TL-ADA; $62.5{\pm}30.3\;mU$) was increased when compared with those from the mild group (TL-ADA; $10.5{\pm}7.5\;mU$) and moderate advanced group (TL-ADA; $13.2{\pm}11.7\;mU$) in active tuberculosis. 4) The albumin level from the BAL fluid was correlated with the ADA activity (R=0.89). 5) The ADA activity recovered from the BAL fluid was correlated with the recovered lymphocyte percentage (R=0.60). In conclusion, the ADA activity from the BAL fluid in active tuberculosis group was increased when compared with that in inactive tuberculosis and control groups, especially from the lesion site. To evaluated the specificity of ADA determination for diagnosis of active tuberculosis, BAL must be done at lesion site of the diseased lung and the proper correcting material other than albumin must be chosen to correct the dilution factor of lavage fluid.

• Tuberculosis and Respiratory Diseases
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• v.46 no.2
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• pp.215-228
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• 1999

Background: Sarcoidosis is a chronic granulomatous inflammatory disease of unknown etiology often involving the lungs and intrathoracic lymph nodes. The natural course of sarcoidosis is variable from spontaneous remission to significant morbidity or death. But, the mechanisms causing the variable clinical outcomes or any single parameter to predict the prognosis was not known. In sarcoidosis, the number and the activity of CD4 + lymphocytes are significantly increased at the loci of disease and their oligoclonality suggests that the CD4 + lymphocytes hyperreactivity may be caused by persistent antigenic stimulus. Recently, it has been known that CD4+ lymphocytes can be subdivided into 2 distinct population(Th1 and Th2) defined by the spectrum of cytokines produced by these cells. Th1 cells promote cellular immunity associated with delayed type hypersensitivity reactions by generating IL-2 and IFN-$\gamma$. Th2 cells playa role in allergic responses and immediate hypersensitivity reactions by secreting IL-4, IL-5, and IL-10. CD4+ lymphocytes in pulmonary sarcoidosis were reported to be mainly Th1 cells. IL-12 has been known to play an important role in differentiation of undifferentiated naive T cells to Th1 cells. And, Moller et al. observed increased IL-12 in bronchoalveolar lavage fluid(BALF) in patients with sarcoidosis. So it is possible that the elevated level of IL-12 is necessary for the continuous progression of the disease in active sarcoidosis. This study was performed to test the assumption that IL-12 can be a marker of active pulmonary sarcoidosis. Methods: We measured the concentration of IL-12 in BALF and in conditioned medium of alveolar macrophage(AM) using ELISA(enzyme-linked immunosorbent assay) method in 26 patients with pulmonary sarcoidosis(10 males, 16 females, mean age: $39.8{\pm}2.1$ years) and 11 normal control. Clinically, 14 patients had active sarcoidosis and 12 patients had inactive. Results: Total cells counts, percentage and number of lymhocytes, number of AM and CD4/CD8 lymphocyte ratio in BALF were significantly higher in patients with sarcoidosis than in control group. But none of these parameters could differentiate active sarcoidosis from inactive disease. The concentration of IL-12 in BALF was significantly increased in sarcoidosis patients ($49.3{\pm}9.2$ pg/ml) than in normal control ($2.5{\pm}0.4$ pg/ml) (p<0.001). Moreover it was significantly higher in patients with active sarcoidosis ($70.3{\pm}14.8$ pg/ml) than in inactive disease ($24.8{\pm}3.l$ pg/ml) (p=0.001). Also, the concentration of IL-12 in BALF showed significant correlation with the percentage of AM(p<0.001), percentage(p<0.001) and number of lymphocyte(p<0.001) in BALF, suggesting the close relationship between the level of IL-12 in BALF and the inflammatory cell infiltration in the lungs. Furthermore, we found a significant correlation between the level of IL-12 and the concentration of soluble ICAM-1 : in serum(p<0.001) and BALF (p=0.001), and also between IL-12 level and ICAM-1 expression of AM(p<0.001). The AM from patients with pulmonary sarcoidosis secreted significantly larger amount of IL-12 ($206.2{\pm}61.9$ pg/ml) than those of control ($68.3{\pm}43.7$ pg/ml) (p<0.008), but, there was no difference between inactive and active disease group. Conclusion : Our data suggest that the BALF IL-12 level can be used as a marker of the activity of pulmonary sarcoidosis.