• Korean Journal of Pharmacognosy
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• v.17 no.3
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• pp.248-254
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• 1986

Effects of vinblastine(VLB) and vincristine(VCR) on cell-mediated immunity(CMI) were studied with the microcytotoxicity test(MCT) after normal or pre-sensitized Balb/c mice had been treated in vivo with a combination of two different doses of VLB or VCR(single dose of 20% and 60% $LD_{50}$, i.p.) at different times (from day -6 to day +4) plus allo-transplantation antigen(allo-TA, cells from C3H mice at day 0). The results were that $LD_{50}$ of VLB for female Balb/c mouse was 7.3mg/kg body weight (i.p.) and $LD_{50}$ of VCR was 4.3mg/kg body weight and that VLB and VCR acted as immunosuppressive agents on the primary CMI when administered after allo-TA(antigen-drug-phase), but showed no effect when administered prior to allo-TA(drug-antigen-phase). Change of doses of VLB and VCR(20% $LD_{50}$, 60% $LD_{50}$) caused quantitative or qualitative variations in the immunomodulating effects of these two drugs. Neither VLB nor VCR had any immunomodulating effect on the secondary CMI. Lastly, the results support that the four parameters (type of drug, sensitization status, time of drug treatment in relation to antigen injection, and drug dosis) are significant for the effects of the VLB and VCR on the CMI, and that VLB and VCR may inhibit the proliferation of antigen-stimulated T effector lymphocytes but not memory-cytotoxic T lymphocytes.

• Journal of Microbiology and Biotechnology
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• v.31 no.1
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• pp.25-32
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• 2021

Inflammatory reactions activated by lipopolysaccharide (LPS) of gram-negative bacteria can lead to severe septic shock. With the recent emergence of multidrug-resistant gram-negative bacteria and a lack of efficient ways to treat resulting infections, there is a need to develop novel anti-endotoxin agents. Antimicrobial peptides have been noticed as potential therapeutic molecules for bacterial infection and as candidates for new antibiotic drugs. We previously designed the 9-meric antimicrobial peptide Pro9-3 and it showed high antimicrobial activity against gram-negative bacteria. Here, to further examine its potency as an anti-endotoxin agent, we examined the anti-endotoxin activities of Pro9-3 and elucidated its mechanism of action. We performed a dye-leakage experiment and BODIPY-TR cadaverine and limulus amebocyte lysate assays for Pro9-3 as well as its lysine-substituted analogue and their enantiomers. The results confirmed that Pro9-3 targets the bacterial membrane and the arginine residues play key roles in its antimicrobial activity. Pro9-3 showed excellent LPS-neutralizing activity and LPS-binding properties, which were superior to those of other peptides. Saturation transfer difference-nuclear magnetic resonance experiments to explore the interaction between LPS and Pro9-3 revealed that Trp3 and Tlr7 in Pro9-3 are critical for attracting Pro9-3 to the LPS in the gram-negative bacterial membrane. Moreover, the anti-septic effect of Pro9-3 in vivo was investigated using an LPS-induced endotoxemia mouse model, demonstrating its dual activities: antibacterial activity against gram-negative bacteria and immunosuppressive effect preventing LPS-induced endotoxemia. Collectively, these results confirmed the therapeutic potential of Pro9-3 against infection of gram-negative bacteria.

• Biomolecules & Therapeutics
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• v.29 no.5
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• pp.536-544
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• 2021

5-amino salicylic acid (5-ASA) is a standard therapy for the treatment of mild to moderate forms of inflammatory bowel diseases (IBD) whereas more severe forms involve the use of steroids and immunosuppressive drugs. Hyaluronic acid (HA) is a naturally occurring non-sulfated glycosaminoglycan that has shown epithelium protective effects in experimental colitis recently. In this study, both 5-ASA (30 mg/kg) and HA (15 mg/kg or 30 mg/kg) were administered rectally and investigated for their potential complementary therapeutic effects in moderate or severe murine colitis models. Intrarectal treatment of moderate and severe colitis with 5-ASA alone or HA alone at a dose of 30 mg/kg led to a significant decrease in clinical activity and histology scores, myeloperoxidase activity (MPO), TNF-α, IL-6 and IL-1β in colitis mice compared to untreated animals. The combination of HA (30 mg/kg) and 5-ASA in severe colitis led to a significant improvement of colitis compared to 5-ASA alone. Combined rectal therapy with HA and 5-ASA could be a treatment alternative for severe cases of IBD as it was the only treatment tested that was not significantly different from the healthy control group. This study further underlines the benefit of searching for yet unexplored drug combinations that show therapeutic potential in IBD without the need of designing completely new drug entities.

• Korean Circulation Journal
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• v.53 no.6
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• pp.351-366
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• 2023

Along with the development of immunosuppressive drugs, major advances on xenotransplantation were achieved by understanding the immunobiology of xenograft rejection. Most importantly, three predominant carbohydrate antigens on porcine endothelial cells were key elements provoking hyperacute rejection: α1,3-galactose, SDa blood group antigen, and N-glycolylneuraminic acid. Preformed antibodies binding to the porcine major xenoantigen causes complement activation and endothelial cell activation, leading to xenograft injury and intravascular thrombosis. Recent advances in genetic engineering enabled knock-outs of these major xenoantigens, thus producing xenografts with less hyperacute rejection rates. Another milestone in the history of xenotransplantation was the development of co-stimulation blockaded strategy. Unlike allotransplantation, xenotransplantation requires blockade of CD40-CD40L pathway to prevent T-cell dependent B-cell activation and antibody production. In 2010s, advanced genetic engineering of xenograft by inducing the expression of multiple human transgenes became available. So-called 'multi-gene' xenografts expressing human transgenes such as thrombomodulin and endothelial protein C receptor were introduced, which resulted in the reduction of thrombotic events and improvement of xenograft survival. Still, there are many limitations to clinical translation of cardiac xenotransplantation. Along with technical challenges, zoonotic infection and physiological discordances are major obstacles. Social barriers including healthcare costs also need to be addressed. Although there are several remaining obstacles to overcome, xenotransplantation would surely become the novel option for millions of patients with end-stage heart failure who have limited options to traditional therapeutics.

• Childhood Kidney Diseases
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• v.18 no.1
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• pp.18-23
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• 2014

Purpose: The pharmacokinetics of tacrolimus, one of the most widely used immunosuppressive drugs, are known to vary by sex, age, and ethnicity during pediatric transplantation. This study assessed the pharmacokinetic characteristics and associated factors of tacrolimus in Korean children receiving a kidney transplant. Methods: We retrospectively reviewed the pharmacokinetic data (therapeutic dose, trough level, clearance, and half-life) of 9 children who were given tacrolimus as one of their initial immunosuppressive drugs after kidney transplantation. In addition, we compared the findings to data from 10 adult kidney transplant recipients. Results: The mean age of our pediatric patients was 13.9 years, and the maleto- female ratio was 4:5. The mean dose of tacrolimus was $0.19{\pm}0.14$ mg/kg/day. The mean dose of tacrolimus for males was $0.23{\pm}0.12$ mg/kg/day, which was significantly higher than the dose for females ($0.16{\pm}0.14$ mg/kg/day). The trough level was not significantly different between both groups. The clearance rate of tacrolimus for males was also significantly higher than females. Although the dosage of tacrolimus for patients over the age of 12 years was lower ($0.18{\pm}0.13$ vs. $0.21{\pm}0.16$ mg/kg/day) and the trough level was higher ($8.2{\pm}4.5$ vs. $7.2{\pm}4.2$ mg/mL) than that for patients under the age of 12 years, there was no significant difference between them. However, there were significant differences between children and adults in dose, clearance, and half-life of tacrolimus. Conclusion: Out study suggests that the pharmacokinetics of tacrolimus tends to vary with sex and age. Therefore, large-scale prospective studies are required to verify the proper therapeutic dosage of tacrolimus in Korean children.

• Tuberculosis and Respiratory Diseases
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• v.46 no.5
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• pp.685-696
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• 1999

Background : Idiopathic pulmonary fibrosis (IPF) is a diffuse inflammatory and fibrosing process that occurs within the interstitium and alveolus of the lung with invariably poor prognosis. The major problem in management of IPF results from the variable rate of disease progression and the difficulties in predicting the response to therapy. The purpose of this retrospective study was to evaluate the short-term efficacy of steroid and immunosuppressive therapy for IPF and to identify the pre-treatment determinants of favorable response. Method : Twenty patients of IPF were included. Diagnosis of IPF was proven by thoracoscopic lung biopsy and they were presumed to have active progressive disease. The baseline evaluation in these patients included clinical history, pulmonary function test, bronchoalveolar lavage (BAL), and chest high resolution computed tomography (HRCT). Fourteen patients received oral prednisolone treatment with initial dose of 1mg/kg/day for 8 to 12 weeks and then tapering to low-dose prednisolone (0.25mg/kg/day). Six patients who previously had experienced significant side effects to steroid received 2mg/kg/day of oral cyclophosphamide with or without low-dose prednisolone. Follow-up evaluation was performed after 6 months of therapy. If patients met more than one of followings, they were considered to be responders : (1) improvement of more than one grade in dyspnea index, (2) improvement in FVC or TLC more than 10% or improvement in DLco more than 20% (3) decreased extent of disease in chest HRCT findings. Result : One patient died of extrapulmonary cause after 3 month of therapy, and another patient gave up any further medical therapy due to side effect of steroid. Eventually medical records of 18 patients were analyzed. Nine of 18 patients were classified into responders and the other nine patients into nonresponders. The histopathologic diagnosis of the responders were all nonspecific interstitial pneumonia (NSIP) and that of nonresponders were all usual interstitial pneumonia (UIP) (p<0.001). The other significant differences between the two groups were female predominance (p<0.01), smoking history (p<0.001), severe grade of dyspnea (p<0.05), lymphocytosis in BAL fluid ($23.8{\pm}16.3%$ vs $7.8{\pm}3.6%$, p<0.05), and less honeycombing in chest HRCT findings (0% vs $9.2{\pm}2.3%$, p<0.001). Conclusion : Our results suggest that patients with histopathologic diagnosis of NSIP or lymphocytosis in BAL fluid are more likely to respond to steroid or immunosuppressive therapy. Clinical results in large numbers of IPF patients will be required to identify the independent variables.

• Clinical and Experimental Pediatrics
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• v.53 no.3
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• pp.428-431
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• 2010

Thrombotic thrombocytopenic purpura (TTP) is a thrombotic microangiopathy characterized by endothelial cell damage, resulting in microangiopathic hemolytic anemia, thrombocytopenia, and various degrees of neurological and renal impairment caused by microvascular thrombi. It is rare in children and frequently follows a fatal course. TTP is divided into 2 types: one is inherited and associated with ADAMTS-13 gene mutations and the other is acquired and associated with anti-ADAMTS-13 autoantibodies. The measurement of ADAMTS-13 activity in plasma, identification of ADAMTS-13 circulating inhibitor, anti-ADAMTS-13 IgG, and ADAMTS-13 gene sequencing are crucial to the diagnosis of TTP. Plasma exchanges are the first-line treatment for acquired TTP, combined with steroids and immunosuppressive drugs. Here, we describe the case of an adolescent patient with TTP, confirmed by decreased level of ADAMTS-13 activity and an increased level of ADAMTS-13 inhibitor, who was successfully treated by plasma exchanges.

• Tuberculosis and Respiratory Diseases
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• v.45 no.2
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• pp.429-436
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• 1998

Approximately 100 drugs have been reported to affect the lungs adversely. Among these, pulmonary toxicity caused by antieneoplastic agent. is being recognized more frequently. Cyclophosphamide is an immunosuppressive alkylating agent used for the treatment of a wide variety of malignant and nonmalignant diseases. The incidence of pulmonary toxicity is probably less than 1 percent The first case was reported in 1967. Since then, more than 20 well-documented cases of pulmonary toxicity associated with cyclophosphamide have been reported in the literature. In Korea, three patients were identified with cyclophosphamide-induced lung disease. The typical features of toxicity include dyspnea, fever, cough, new parenchymal infiltrates, gas exchangs abnormalities on pulmonary function tests, and pleural thickening on chest roentgenogram. The best approach to management is early diagnosis, discontinuation of the offending drug and administration of corticosteroid therapy. Recently, we experienced a case of diffuse alveolar damage induced by cyclophosphamide. The patient presented with early-onset pulmonary toxicity and died of repiratory failure despite early use of corticosteroid.

• Journal of Chest Surgery
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• v.31 no.5
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• pp.531-535
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• 1998

In 1964, Abbott and Colleagues published the world's first heterotopic heart transplantation technique in the rat. Their method established circulation by end-to-end anastomoses of the graft's aorta and pulmonary artery to the recipient's abdominal aorta and Inferior Vena Cava(IVC), respectively. In 1966, Tomita et al altered Abbott's technique by employing end-to-side rather than end-to-end anastomoses, thus eliminating the hind leg paralysis that sometimes resulted from Abbott's technique. In order to prevent postsuture hemorrhage (since 7-0 silk suture was the finest available at that time), Tomita's aortic anastomosis was done with double up-and-down continuous suture technique. A single layer continuous anstomosis effected the pulmonary artery-IVC anastomosis. The availability of Nylon monofilament suture made it possible for Ono and Lindsey to use a single layer suture technique for the aortic end-to-side anastomosis in their modified rat heart transplantation. We observed survival time between control group and Immunosuppression(Cyclosporine administration, 10mg/Kg${\times}$4 times postoperatively) group after heterotopic heart transplantation in the rat model. The cyclosporine adminstration group survived longer than the control group, thus we concluded that cyclosporine was based on Immunosuppressive drugs.

• Biomolecules & Therapeutics
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• v.29 no.2
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• pp.166-174
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• 2021

Multiple myeloma is a malignant cancer of plasma cells. Despite recent progress with immunomodulatory drugs and proteasome inhibitors, it remains an incurable disease that requires other strategies to overcome its recurrence and non-response. Based on the high expression levels of programmed death-ligand 1 (PD-L1) in human multiple myeloma isolated from bone marrow and the murine myeloma cell lines, NS-1 and MOPC-315, we propose PD-L1 molecule as a target of anti-multiple myeloma therapy. We developed a novel anti-PD-L1 antibody containing a murine immunoglobulin G subclass 2a (IgG2a) fragment crystallizable (Fc) domain that can induce antibody-dependent cellular cytotoxicity. The newly developed anti-PD-L1 antibody showed significant antitumor effects against multiple myeloma in mice subcutaneously, intraperitoneally, or intravenously inoculated with NS-1 and MOPC-315 cells. The anti-PD-L1 effects on multiple myeloma may be related to a decrease in the immunosuppressive myeloid-derived suppressor cells (MDSCs), but there were no changes in the splenic MDSCs after combined treatment with lenalidomide and the anti-PD-L1 antibody. Interestingly, the newly developed anti-PD-L1 antibody can induce antibody-dependent cellular cytotoxicity in the myeloma cells, which differs from the existing anti-PD-L1 antibodies. Collectively, we have developed a new anti-PD-L1 antibody that binds to mouse and human PD-L1 and demonstrated the antitumor effects of the antibody in several syngeneic murine myeloma models. Thus, PD-L1 is a promising target to treat multiple myeloma, and the novel anti-PD-L1 antibody may be an effective anti-myeloma drug via antibody-dependent cellular cytotoxicity effects.