1.Comparison of Optical Genome Mapping With Conventional Diagnostic Methods for Structural Variant Detection in Hematologic Malignancies
Yeeun SHIM ; Yu-Kyung KOO ; Saeam SHIN ; Seung-Tae LEE ; Kyung-A LEE ; Jong Rak CHOI
Annals of Laboratory Medicine 2024;44(4):324-334
Background:
Structural variants (SVs) are currently analyzed using a combination of conventional methods; however, this approach has limitations. Optical genome mapping (OGM), an emerging technology for detecting SVs using a single-molecule strategy, has the potential to replace conventional methods. We compared OGM with conventional diagnostic methods for detecting SVs in various hematologic malignancies.
Methods:
Residual bone marrow aspirates from 27 patients with hematologic malignancies in whom SVs were observed using conventional methods (chromosomal banding analysis, FISH, an RNA fusion panel, and reverse transcription PCR) were analyzed using OGM. The concordance between the OGM and conventional method results was evaluated.
Results:
OGM showed concordance in 63% (17/27) and partial concordance in 37% (10/27) of samples. OGM detected 76% (52/68) of the total SVs correctly (concordance rate for each type of SVs: aneuploidies, 83% [15/18]; balanced translocation, 80% [12/15] unbalanced translocation, 54% [7/13] deletions, 81% [13/16]; duplications, 100% [2/2] inversion 100% [1/1]; insertion, 100% [1/1]; marker chromosome, 0% [0/1];isochromosome, 100% [1/1]). Sixteen discordant results were attributed to the involvement of centromeric/telomeric regions, detection sensitivity, and a low mapping rate and coverage. OGM identified additional SVs, including submicroscopic SVs and novel fusions, in five cases.
Conclusions
OGM shows a high level of concordance with conventional diagnostic methods for the detection of SVs and can identify novel variants, suggesting its potential utility in enabling more comprehensive SV analysis in routine diagnostics of hematologic malignancies, although further studies and improvements are required.
2.An Alternative Dendritic Cell-Induced Murine Model of Asthma Exhibiting a Robust Th2/Th17-Skewed Response
Sang Chul PARK ; Hongmin KIM ; Yeeun BAK ; Dahee SHIM ; Kee Woong KWON ; Chang Hoon KIM ; Joo Heon YOON ; Sung Jae SHIN
Allergy, Asthma & Immunology Research 2020;12(3):537-555
PURPOSE: Simple and reliable animal models of human diseases contribute to the understanding of disease pathogenesis as well as the development of therapeutic interventions. Although several murine models to mimic human asthma have been established, most of them require anesthesia, resulting in variability among test individuals, and do not mimic asthmatic responses accompanied by T-helper (Th) 17 and neutrophils. As dendritic cells (DCs) are known to play an important role in initiating and maintaining asthmatic inflammation, we developed an asthma model via adoptive transfer of allergen-loaded DCs.METHODS: Ovalbumin (OVA)-loaded bone marrow-derived DCs (BMDCs) (OVA-BMDCs) were injected intravenously 3 times into non-anesthetized C57BL/6 mice after intraperitoneal OVA-sensitization.RESULTS: OVA-BMDC-transferred mice developed severe asthmatic immune responses when compared with mice receiving conventional OVA challenge intranasally. Notably, remarkable increases in systemic immunoglobulin (Ig) E and IgG1 responses, Th2/Th17-associated cytokines (interleukin [IL]-5, IL-13 and IL-17), Th2/Th17-skewed T-cell responses, and cellular components, including eosinophils, neutrophils, and goblet cells, were observed in the lungs of OVA-BMDC-transferred mice. Moreover, the asthmatic immune responses and severity of inflammation were correlated with the number of OVA-BMDCs transferred, indicating that the disease severity and asthma type may be adjusted according to the experimental purpose by this method. Furthermore, this model exhibited less variation among the test individuals than the conventional model. In addition, this DCs-based asthma model was partially resistant to steroid treatment.CONCLUSIONS: A reliable murine model of asthma by intravenous (i.v.) transfer of OVA-BMDCs was successfully established without anesthesia. This model more accurately reflects heterogeneous human asthma, exhibiting a robust Th2/Th17-skewed response and eosinophilic/neutrophilic infiltration with good reproducibility and low variation among individuals. This model will be useful for understanding the pathogenesis of asthma and would serve as an alternative tool for immunological studies on the function of DCs, T-cell responses and new drugs.
Adoptive Transfer
;
Anesthesia
;
Animals
;
Asthma
;
Cytokines
;
Dendritic Cells
;
Eosinophils
;
Goblet Cells
;
Humans
;
Immunoglobulin G
;
Immunoglobulins
;
Inflammation
;
Interleukin-13
;
Lung
;
Methods
;
Mice
;
Models, Animal
;
Neutrophils
;
Ovalbumin
;
Ovum
;
T-Lymphocytes
3.Association Between Aortic Valve Sclerosis and Clonal Hematopoiesis of Indeterminate Potential
Minkwan KIM ; Jin Ju KIM ; Seung-Tae LEE ; Yeeun SHIM ; Hyeonah LEE ; SungA BAE ; Nak-Hoon SON ; Saeam SHIN ; In Hyun JUNG
Annals of Laboratory Medicine 2024;44(3):279-288
Background:
The mechanism and medical treatment target for degenerative aortic valve disease, including aortic stenosis, is not well studied. In this study, we investigated the effect of clonal hematopoiesis of indeterminate potential (CHIP) on the development of aortic valve sclerosis (AVS), a calcified aortic valve without significant stenosis.
Methods:
Participants with AVS (valves ≥ 2 mm thick, high echogenicity, and a peak trans-aortic velocity of < 2.5 m/sec) and an age- and sex-matched control group were enrolled.Twenty-four CHIP genes with common variants in cardiovascular disease were used to generate a next-generation sequencing panel. The primary endpoint was the CHIP detection rate between the AVS and control groups. Inverse-probability treatment weighting (IPTW) analysis was performed to adjust for differences in baseline characteristics.
Results:
From April 2020 to April 2022, 187 participants (125 with AVS and 62 controls) were enrolled; the mean age was 72.6 ± 8.5 yrs, and 54.5% were male. An average of 1.3CHIP variants was observed. CHIP detection, defined by a variant allele frequency (VAF) of≥ 0.5%, was similar between the groups. However, the AVS group had larger CHIP clones:49 (39.2%) participants had a VAF of ≥ 1% (vs. 13 [21.0%] in the control group; P = 0.020), and 25 (20.0%) had a VAF of ≥ 2% (vs. 4 [6.5%]; P = 0.028). AVS is independently associated with a VAF of ≥ 1% (adjusted odds ratio: 2.44, 95% confidence interval: 1.11–5.36; P = 0.027). This trend was concordant and clearer in the IPTW cohort.
Conclusions
Participants with AVS more commonly had larger CHIP clones than age- and sex-matched controls. Further studies are warranted to identify causality between AVS and CHIP.