1.Optimization of Natural Killer Cell Expansion with K562-mbIL-18/-21 Feeder Cells and Assurance of Feeder Cell-Free Products
Hantae JO ; Yujung JO ; Seung Kwon KOH ; Mijeong LEE ; Jinho KIM ; SoonHo KWEON ; Jeehun PARK ; Hyun‑Young KIM ; Duck CHO
Annals of Laboratory Medicine 2026;46(2):180-189
Background:
Cancer cell line-derived feeder cells enhance natural killer (NK) cell expansion; however, concerns regarding viable residual feeder cells in the final product limit their use. Evidence supporting the safety of NK-sensitive K562-based feeders, even when irradiated, is scarce. We optimized an NK cell expansion protocol using genetically engineered K562-mbIL-18/-21 (GE-K562) feeder cells and clinical-grade media and confirmed the absence of residual feeder cells.
Methods:
NK cell expansion efficiency was compared between feeder-free and feederbased systems using CTS NK-Xpander Medium. To achieve optimal NK expansion, various peripheral blood mononuclear cell (PBMC)-to-feeder ratios and re-stimulation frequencies were tested over 21 days. Flow cytometry and BCR::ABL1 quantitative reverse transcription PCR (RT-qPCR) were used to confirm the absence of feeder cells in the final NK cell product.
Results:
Feeder-based systems showed superior NK cell fold expansion compared with that of feeder-free systems. Among feeder-based conditions, NK cells expanded 5,224-fold at a 2:1 PBMC-to-feeder ratio after 3 weeks, relative to 1,450-fold at a 6:1 ratio (P < 0.05).Re-stimulation on days 7 and 14 further increased expansion up to 261,457-fold. Irradiated feeder cells showed no proliferation and were eliminated within 3–6 days. On day 21, flow cytometry and BCR::ABL1 RT-qPCR results confirmed the absence of residual feeder cells.
Conclusions
Our optimized NK cell expansion protocol using irradiated GE-K562 feeder cells and clinical-grade media offers a safe and scalable approach to generating large numbers of NK cells, supporting its potential use in clinical immunotherapy applications.
2.A Protocol of Korean JOint RegistrY for ALZheimer’s Treatment and Diagnostics (JOY-ALZ)
Geon Ha KIM ; Jung-Min PYUN ; Danbee KANG ; Sung Hoon KANG ; Seong-Ho KOH ; Jae Seung KIM ; So Young MOON ; Won-Jin MOON ; Young Ho PARK ; YongSoo SHIM ; Dong Won YANG ; Young Chul YOUN ; Young Hee JUNG ; Hanna CHO ; Hojin CHOI ; Jae-Sung LIM ; Kee Hyung PARK ; Seong Hye CHOI
Dementia and Neurocognitive Disorders 2026;25(1):25-41
Background:
and Purpose: To assess the long-term effectiveness, safety, and economic viability of recently approved Alzheimer’s disease (AD) therapies, as well as to evaluate the real-world application of novel diagnostics among AD patients with diverse comorbidities, comprehensive real-world data (RWD) analysis is essential. The Korean JOint RegistrY for ALZheimer’s Treatment and Diagnostics (JOY-ALZ) endeavors to create a registry of RWD derived from clinical practice on new diagnostic methods and therapeutic agents for AD introduced in Korea since 2021.
Methods:
Participants must fulfill all the following: 1) be at least 19 years old; 2) be actively receiving, scheduled to initiate, or undergoing evaluation for any AD disease-modifying treatment; 3) have completed amyloid positron emission tomography or cerebrospinal fluid AD immunoassay (a positive result is not essential for participation); 4) have a clinical classification of cognitively unimpaired, mild cognitive impairment, or probable AD dementia. Data generated during routine care is segmented into a minimum dataset, extended dataset, and research-only dataset requiring extra consent. Assessments encompass clinical, cognitive, functional, neurobehavioral, neuroimaging, and biomarker evaluations, in addition to systematic monitoring of new AD treatments and their safety.Data are collected and monitored at baseline, at semiannual intervals during the initial 2 years, and then annually up to 2034. To date, 46 medical centers will participate in JOY-ALZ.
Conclusions
JOY-ALZ is expected to promote understanding of the long-term clinical outcomes, safety, and cost-effectiveness of recently introduced diagnostics and treatments for AD, thereby supporting the progress of precision medicine in AD care and diagnosis.
3.Feasibility and Preliminary Efficacy of Digital Cognitive Training in Parkinson’s Disease With Mild Cognitive Impairment: A Pilot Study
Dongje LEE ; Hang-Rai KIM ; Yu Jeong PARK ; Yisuh AHN ; Daeho LEE ; Jungyeun LEE ; Su Jin CHUNG ; Seung Yeon KIM ; Yeji HWANG ; Ji Young YUN ; Jin Whan CHO ; Kyum-Yil KWON ; Seong-Beom KOH ; Sung Hoon KANG
Journal of Movement Disorders 2026;19(1):76-80
Objective:
Cognitive impairment is common in patients with Parkinson’s disease (PD), and few pharmacological options are available for treating this condition. We evaluated the effects of a digital cognitive training program (SUPERBRAIN), which was previously shown to be effective in populations at risk of Alzheimer’s disease, on cognitive function in individuals with PD.
Methods:
Twenty-three individuals with PD and mild cognitive impairment (PD-MCI) from four clinics were randomized to the intervention (n=16) or control (n=7) groups. The intervention group completed a 12-week, home-based, tablet-based cognitive training program (25–30 min/day, 7 days/week). Cognitive outcomes were assessed using the Seoul Neuropsychological Screening Battery pre- and post-intervention.
Results:
The adherence rate was 79.36%. The intervention group showed significant improvements in the Seoul Verbal Learning Test (SVLT) delayed recall and the Controlled Oral Word Association Test, while no changes were observed in the control group. Analysis of covariance confirmed greater SVLT improvement in the intervention group (F statistic=7.15, p=0.015, partial η2=0.28).
Conclusion
SUPERBRAIN is feasible and can improve cognitive function in individuals with PD-MCI.
4.Clinical and Urodynamic Predictors of Urinary Urgency Improvement After Cystocele Repair
Ju Hun AHN ; Joon Chul KIM ; Jin Bong CHOI ; Jun Sung KOH ; Young Kyu HAN ; Seong Joo YANG ; Kang Jun CHO
International Neurourology Journal 2026;30(2):163-171
Purpose:
Overactive bladder (OAB) symptoms may improve following surgical correction of cystocele. This study aimed to evaluate changes in urgency, the primary symptom of OAB, and identify factors associated with improvement in urgency after surgical treatment for cystocele.
Methods:
We conducted a retrospective analysis of medical records for patients who underwent surgical treatment for cystocele and had preoperative urgency measuring ≥3 on a 5-point urinary sensation scale. Patients were categorized into 2 groups based on their urgency status 3 months postsurgery: those with improved urgency and those without improvement. Improvement was defined as a reduction of 2 or more points on the scale following surgery. We compared preoperative clinical and urodynamic factors between the 2 groups.
Results:
A total of 137 patients were included in the study, with 98 (71.5%) showing improvement in urgency symptoms after surgery. The improved group had a significantly higher prevalence of preoperative urgency urinary incontinence (UUI) (62.2% vs. 30.8%, P=0.001) and bladder outlet obstruction (43.9% vs. 20.5%, P=0.011) compared to the nonimproved group. Urodynamic evaluations indicated that the detrusor pressure at maximum flow rate (PdetQmax) was significantly higher in the improved group than in the nonimproved group (P=0.004). Multivariate logistic regression analysis identified preoperative UUI, higher PdetQmax, and lower vaginal parity as independent predictors of improvement in urgency postoperatively.
Conclusions
Preoperative UUI, higher PdetQmax, and lower vaginal parity were significant predictors of postoperative improvement in urgency. Both clinical and urodynamic factors may help identify patients with cystocele and preoperative urgency who are most likely to benefit from anatomical correction.
5.Constitutional Chromosome 21 Abnormality in B-ALL with iAMP21 in a Patient Developing Treatment-Related Myelodysplastic Syndrome
Inhwa KIM ; Su Hyun YOON ; Sunghan KANG ; Kyung-Nam KOH ; Mi Young KIM ; Young-Uk CHO ; Sang-Hyun HWANG ; Seongsoo JANG ; Eul-Ju SEO ; Beom Hee LEE ; Sunghee MIN ; Hyunwoo BAE ; Ho Joon IM ; Hyery KIM
Clinical Pediatric Hematology-Oncology 2025;32(1):23-28
The initial molecular cytogenetic characteristics of blasts plays a significant role in determining the treatment course of B-cell acute lymphoblastic leukemia (B-ALL).B-ALL with intrachromosomal amplification of chromosome 21 (iAMP21) has been well known to have unfavorable prognosis. Also, there are previously recognized germline mutations that increase the risk of ALL, such as trisomy 21, Down syndrome. This case report is about a 16-year-old girl who presented with lymphadenitis, purpura, and fever followed by initial lab of elevated white blood cell with blasts.She had some notable facial features, but no typical Down syndrome related one.Bone marrow biopsy and fluorescence in situ hybridization finalized the diagnosis as B-ALL with iAMP21, high-risk group. The minimal residual disease-negative complete remission was achieved after the induction chemotherapy with Korean multicenter high-risk protocol. However, abnormal karyotype was sustained in bone marrow. Microarrays with her buccal swab raised the possibility that the abnormal karyotype was not from the leukemic blasts but rather from the germline. Although she underwent scheduled chemotherapy uneventfully as slow early responder type, thrombocytopenia and abnormal karyotype persisted, leading to the diagnosis of acute myeloid leukemia. Additional chemotherapy and peripheral blood stem cell transplantation was performed which resulted in engraftment. This case highlights the discovery of a constitutional genetic aberration, which played like a silent yet critical background factor for B-ALL with iAMP21. As the number of reported cases are limited, the role of germline chromosome 21 mutation as the indicator for prognosis of B-ALL should be studied further.
6.Carnitine Metabolite as a Potential Circulating Biomarker for Sarcopenia in Men
Je Hyun SEO ; Jung-Min KOH ; Han Jin CHO ; Hanjun KIM ; Young‑Sun LEE ; Su Jung KIM ; Pil Whan YOON ; Won KIM ; Sung Jin BAE ; Hong-Kyu KIM ; Hyun Ju YOO ; Seung Hun LEE
Endocrinology and Metabolism 2025;40(1):93-102
Background:
Sarcopenia, a multifactorial disorder involving metabolic disturbance, suggests potential for metabolite biomarkers. Carnitine (CN), essential for skeletal muscle energy metabolism, may be a candidate biomarker. We investigated whether CN metabolites are biomarkers for sarcopenia.
Methods:
Associations between the CN metabolites identified from an animal model of sarcopenia and muscle cells and sarcopenia status were evaluated in men from an age-matched discovery (72 cases, 72 controls) and a validation (21 cases, 47 controls) cohort.
Results:
An association between CN metabolites and sarcopenia showed in mouse and cell studies. In the discovery cohort, plasma C5-CN levels were lower in sarcopenic men (P=0.005). C5-CN levels in men tended to be associated with handgrip strength (HGS) (P=0.098) and were significantly associated with skeletal muscle mass (P=0.003). Each standard deviation increase in C5-CN levels reduced the odds of low muscle mass (odd ratio, 0.61; 95% confidence interval [CI], 0.42 to 0.89). The area under the receiver operating characteristic curve (AUROC) of CN score using a regression equation of C5-CN levels, for sarcopenia was 0.635 (95% CI, 0.544 to 0.726). In the discovery cohort, addition of CN score to HGS significantly improved AUROC from 0.646 (95% CI, 0.575 to 0.717; HGS only) to 0.727 (95% CI, 0.643 to 0.810; P=0.006; HGS+CN score). The improvement was confirmed in the validation cohort (AUROC=0.563; 95% CI, 0.470 to 0.656 for HGS; and AUROC=0.712; 95% CI, 0.569 to 0.855 for HGS+CN score; P=0.027).
Conclusion
C5-CN, indicative of low muscle mass, is a potential circulating biomarker for sarcopenia in men. Further studies are required to confirm these results and explore sarcopenia-related metabolomic changes.
7.Constitutional Chromosome 21 Abnormality in B-ALL with iAMP21 in a Patient Developing Treatment-Related Myelodysplastic Syndrome
Inhwa KIM ; Su Hyun YOON ; Sunghan KANG ; Kyung-Nam KOH ; Mi Young KIM ; Young-Uk CHO ; Sang-Hyun HWANG ; Seongsoo JANG ; Eul-Ju SEO ; Beom Hee LEE ; Sunghee MIN ; Hyunwoo BAE ; Ho Joon IM ; Hyery KIM
Clinical Pediatric Hematology-Oncology 2025;32(1):23-28
The initial molecular cytogenetic characteristics of blasts plays a significant role in determining the treatment course of B-cell acute lymphoblastic leukemia (B-ALL).B-ALL with intrachromosomal amplification of chromosome 21 (iAMP21) has been well known to have unfavorable prognosis. Also, there are previously recognized germline mutations that increase the risk of ALL, such as trisomy 21, Down syndrome. This case report is about a 16-year-old girl who presented with lymphadenitis, purpura, and fever followed by initial lab of elevated white blood cell with blasts.She had some notable facial features, but no typical Down syndrome related one.Bone marrow biopsy and fluorescence in situ hybridization finalized the diagnosis as B-ALL with iAMP21, high-risk group. The minimal residual disease-negative complete remission was achieved after the induction chemotherapy with Korean multicenter high-risk protocol. However, abnormal karyotype was sustained in bone marrow. Microarrays with her buccal swab raised the possibility that the abnormal karyotype was not from the leukemic blasts but rather from the germline. Although she underwent scheduled chemotherapy uneventfully as slow early responder type, thrombocytopenia and abnormal karyotype persisted, leading to the diagnosis of acute myeloid leukemia. Additional chemotherapy and peripheral blood stem cell transplantation was performed which resulted in engraftment. This case highlights the discovery of a constitutional genetic aberration, which played like a silent yet critical background factor for B-ALL with iAMP21. As the number of reported cases are limited, the role of germline chromosome 21 mutation as the indicator for prognosis of B-ALL should be studied further.
8.Carnitine Metabolite as a Potential Circulating Biomarker for Sarcopenia in Men
Je Hyun SEO ; Jung-Min KOH ; Han Jin CHO ; Hanjun KIM ; Young‑Sun LEE ; Su Jung KIM ; Pil Whan YOON ; Won KIM ; Sung Jin BAE ; Hong-Kyu KIM ; Hyun Ju YOO ; Seung Hun LEE
Endocrinology and Metabolism 2025;40(1):93-102
Background:
Sarcopenia, a multifactorial disorder involving metabolic disturbance, suggests potential for metabolite biomarkers. Carnitine (CN), essential for skeletal muscle energy metabolism, may be a candidate biomarker. We investigated whether CN metabolites are biomarkers for sarcopenia.
Methods:
Associations between the CN metabolites identified from an animal model of sarcopenia and muscle cells and sarcopenia status were evaluated in men from an age-matched discovery (72 cases, 72 controls) and a validation (21 cases, 47 controls) cohort.
Results:
An association between CN metabolites and sarcopenia showed in mouse and cell studies. In the discovery cohort, plasma C5-CN levels were lower in sarcopenic men (P=0.005). C5-CN levels in men tended to be associated with handgrip strength (HGS) (P=0.098) and were significantly associated with skeletal muscle mass (P=0.003). Each standard deviation increase in C5-CN levels reduced the odds of low muscle mass (odd ratio, 0.61; 95% confidence interval [CI], 0.42 to 0.89). The area under the receiver operating characteristic curve (AUROC) of CN score using a regression equation of C5-CN levels, for sarcopenia was 0.635 (95% CI, 0.544 to 0.726). In the discovery cohort, addition of CN score to HGS significantly improved AUROC from 0.646 (95% CI, 0.575 to 0.717; HGS only) to 0.727 (95% CI, 0.643 to 0.810; P=0.006; HGS+CN score). The improvement was confirmed in the validation cohort (AUROC=0.563; 95% CI, 0.470 to 0.656 for HGS; and AUROC=0.712; 95% CI, 0.569 to 0.855 for HGS+CN score; P=0.027).
Conclusion
C5-CN, indicative of low muscle mass, is a potential circulating biomarker for sarcopenia in men. Further studies are required to confirm these results and explore sarcopenia-related metabolomic changes.
9.Rapid Recovery From SARS-CoV-2Infection Among Immunocompromised Children Despite Limited Neutralizing Antibody Response: A Virologic and Sero-Immunologic Analysis of a Single-Center Cohort
Doo Ri KIM ; Byoung Kwon PARK ; Jin Yang BAEK ; Areum SHIN ; Ji Won LEE ; Hee Young JU ; Hee Won CHO ; Keon Hee YOO ; Ki Woong SUNG ; Chae-Hong JEONG ; Tae Yeul KIM ; June-Young KOH ; Jae-Hoon KO ; Yae-Jean KIM
Journal of Korean Medical Science 2025;40(12):e52-
Background:
Immunocompromised (IC) pediatric patients are at increased risk of severe acute respiratory syndrome coronavirus 2 infection, but the viral kinetics and seroimmunologic response in pediatric IC patients are not fully understood.
Methods:
From April to June 2022, a prospective cohort study was conducted. IC pediatric patients hospitalized for coronavirus disease 2019 (COVID-19) were enrolled. Serial saliva swab and serum specimens were subjected to reverse transcription polymerase chain reaction assays with mutation sequencing, viral culture, anti-spike-protein, anti-nucleocapsid antibody assays, plaque reduction neutralization test (PRNT) and multiplex cytokine assays.
Results:
Eleven IC children were evaluated. Their COVID-19 symptoms resolved promptly (median, 2.5 days; interquartile range, 2.0–4.3). Saliva swab specimens contained lower viral loads than nasopharyngeal swabs (P = 0.008). All cases were BA.2 infection, and 45.5% tested negative within 14 days by saliva swab from symptom onset. Eight (72.7%) showed a time-dependent increase in BA.2 PRNT titers, followed by rapid waning. Multiplex cytokine assays revealed that monocyte/macrophage activation and Th 1 responses were comparable to those of non-IC adults. Activation of interleukin (IL)-1Ra and IL-6 was brief, and IL-17A was suppressed. Activated interferon (IFN)-γ and IL-18/IL-1F4 signals were observed.
Conclusion
IC pediatric patients rapidly recovered from COVID-19 with low viral loads.Antibody response was limited, but cytokine analysis suggested an enhanced IFN-γ- and IL-18-mediated immune response without excessive activation of inflammatory cascades. To validate our observation, immune cell-based functional studies need to be conducted among IC and non-IC children.
10.Efficacy and Safety of Taltirelin Hydrate in Patients With Ataxia Due to Spinocerebellar Degeneration
Jin Whan CHO ; Jee-Young LEE ; Han-Joon KIM ; Joong-Seok KIM ; Kun-Woo PARK ; Seong-Min CHOI ; Chul Hyoung LYOO ; Seong-Beom KOH
Journal of Movement Disorders 2025;18(1):35-44
Objective:
We conducted this study to assess the efficacy and safety of taltirelin hydrate (TH) in patients with ataxia due to spinocerebellar degeneration (SCD).
Methods:
Patients were randomly assigned to either the taltirelin group (5 mg orally, twice daily) or the control group. The primary endpoint was the change in the Korean version of the Scale for the Assessment and Rating of Ataxia (K-SARA) score at 24 weeks. The secondary endpoints included changes in the K-SARA score at 4 and 12 weeks as well as the Clinical Global Impression Scale, the five-level version of the EuroQol five-dimensional questionnaire, the Tinetti balance test, and gait analysis at 4, 12, and 24 weeks.
Results:
A total of 149 patients (hereditary:nonhereditary=86:63) were enrolled. There were significant differences in the change in the K-SARA score at 24 weeks from baseline between the taltirelin group and the control group (-0.51±2.79 versus 0.36±2.62, respectively; p=0.0321). For the K-SARA items, the taltirelin group had significantly lower “Stance” and “Speech disturbance” subscores than the control group (-0.04±0.89 versus 0.23±0.79 and -0.07±0.74 versus 0.18±0.67; p=0.0270 and 0.0130, respectively). However, there were no significant differences in changes in other secondary efficacy outcome measures at 24 weeks from baseline between the two treatment arms (p>0.05).
Conclusion
Clinicians might consider the use of TH in the treatment of patients with ataxia due to SCD.

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