OBJECTIVE: To prepare clinical-grade human umbilical cord-derived mesenchymal stem cells (hUC-MSC) with high expression of hematopoietic supporting factors and evaluate their stem cell characteristics. METHODS: Fetal umbilical cord tissues were collected from healthy postpartum women during full-term cesarean section. Wharton's jelly was mechanically separated and hUC-MSCs were obtained by explant culture method and enzyme digestion method in an animal serum-free culture system with addition of human platelet lysate. The phenotypic characteristics of hUC-MSCs obtained by two methods were detected by flow cytometry. The differences in proliferation ability between the two groups of hUC-MSCs were identified through CCK-8 assay and colony forming unit-fibroblast (CFU-F) assay. The differences in multilineage differentiation potential between the two groups of hUC-MSCs were identified through induction of adipogenic, osteogenic, and chondrogenic differentiation. The mRNA expression levels of hematopoietic supporting factors such as SCF, IL-3, CXCL12, VCAM1 and ANGPT1 in the two groups of hUC-MSCs were identified by real-time fluorescence quantiative PCR(RT-qPCR). RESULTS: The results of flow cytometry showed that hUC-MSCs obtained by the two methods both expressed high levels of CD73, CD90 and CD105, while lowly expressed CD31, CD45 and HLA-DR. The results of CCK-8 and CFU-F assay showed that the proliferation ability of hUC-MSCs obtained by explant culture method was better than those obtained by enzyme digestion method. The results of the triple lineage differentiation experiment showed that there was no significant difference in multilineage differentiation potential between the two grous of hUC-MSCs. The results of RT-qPCR showed that the mRNA expression levels of hematopoietic supporting factors SCF, IL-3, CXCL12, VCAM1 and ANGPT1 in hUC-MSCs obtained by explant cultrue method were higher than those obtained by enzyme digestion method. CONCLUSION Clinical-grade hUC-MSCs with high expression levels of hematopoietic supporting factors were successfully cultured in an animal serum-free culture system.
Humans ; Mesenchymal Stem Cells/metabolism* ; Umbilical Cord/cytology* ; Cell Differentiation ; Female ; Cell Proliferation ; Cells, Cultured ; Chemokine CXCL12/metabolism* ; Angiopoietin-1/metabolism* ; Vascular Cell Adhesion Molecule-1/metabolism* ; Stem Cell Factor/metabolism* ; Flow Cytometry ; Pregnancy

OBJECTIVE: To investigate the biological effect of medical recombinant human-derived collagen functional dressings in wound healing. METHODS: MTT assay and RTCA assay were used to detect cell toxicity and proliferation. Scratch assay and Transwell cell migration assay were used to detect cell motility and migration ability. Enzyme-linked immunosorbent assay was used to detect the contents of vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF), and platelet-endothelial cell adhesion molecule (CD31) in the supernatant of four types of cells. After animal surgery, the surgical wound was taken at 1 week, 4 weeks and 13 weeks, respectively, for hematoxylin eosin (HE) staining and immunohistochemistry to observe the inflammatory response and CD31 expression of the wound. RESULTS: Medical recombinant human-derived collagen functional dressing promotes cell proliferation and migration, enhances wound angiogenesis by upregulating the expression of VEGF, FGF, and CD31 in human dermal vascular endothelial cells (HDVEC) and human vascular endothelial cells (HVEC), thereby improving local blood supply to the wound, regulating the inflammatory response of the wound, and accelerating wound healing. CONCLUSION Recombinant type Ⅲ humanized collagen plays an important role in wound healing.
Humans ; Wound Healing/drug effects* ; Recombinant Proteins/pharmacology* ; Animals ; Cell Proliferation ; Cell Movement ; Collagen/pharmacology* ; Vascular Endothelial Growth Factor A/metabolism* ; Bandages ; Platelet Endothelial Cell Adhesion Molecule-1/metabolism* ; Endothelial Cells ; Fibroblast Growth Factors/metabolism*

OBJECTIVE: To evaluate the risks and benefits of different resuscitation fluids in patients with early sepsis and septic shock by observing and comparing clinical indicators, clinical outcomes, and the concentration changes of glycocalyx biomarkers, and to determine how to appropriately select suitable resuscitation fluids for sepsis patients to aid fluid therapy. METHODS: A single center, prospective, randomized controlled trial was conducted. Patients with early sepsis and septic shock who have required fluid resuscitation after capacity status assessment admitted to the department of critical care medicine of Fourth Hospital of Hebei Medical University from April to October 2023 were enrolled. Patients were randomly assigned to either the experimental group (balanced crystalloid solution+albumin) or the control group (balanced crystalloid solution) by a random number table method. Clinical data of both groups of patients before and after resuscitation at 3, 8, and 24 hours were monitored, and blood samples were collected, enzyme-linked immunosorbent assay (ELISA) was used to measure the concentration of plasma glycocalyx biomarker syndecan-1. The 28-day and 90-day survival rates and complications were also assessed. RESULTS: A total of 66 patients were enrolled, including 44 in the experimental group and 22 in the control group. The baseline data of two groups were balanced and comparable. There was no statistically significant difference in the plasma concentration of syndecan-1 between the experimental group and the control group before and after resuscitation, and both showed a trend of first increasing and then decreasing. However, the plasma syndecan-1 level in the control group at 8 hours and 24 hours after resuscitation were significantly higher than the baseline level before resuscitation [ng/L: 19.02 (14.41, 27.80), 18.95 (12.40, 22.50) vs. 14.67 (11.57, 21.14), both P < 0.05], while there was no statistically significant difference at any time point within the experimental group. The correlation analysis between plasma syndecan-1 level and lactic acid, albumin, and sequential organ failure assessment (SOFA) in all patients showed that a positive correlation between syndecan-1 level and SOFA score before resuscitation (r = 0.247, P = 0.046), and a negative correlation between syndecan-1 level and albumin level at 24 hours after resuscitation (r = -0.308, P = 0.012). There were no statistically significant differences in 28-day and 90-day mortality, length of hospital stay, length of intensive care unit (ICU) stay, duration of mechanical ventilation, blood purification time, number of organ injuries, and complications between the two groups. However, the baseline albumin level in the experimental group was significantly lower than that in the control group (g/L: 28.7±4.5 vs. 31.6±4.2, P < 0.05). Analysis of clinical treatment data showed that compared with the control group, the experimental group had lower absolute lactate level at 8 hours and 24 hours after resuscitation [mmol/L: 8 hours was 1.30 (1.00, 1.88) vs. 1.60 (1.30, 3.05), 24 hours was 1.15 (0.80, 1.78) vs. 1.55 (1.08, 2.05), both P < 0.05], and higher lactate clearance rate [8 hours was 45% (27%, 56%) vs. 20% (-4%, 46%), 24 hours was 55% (34%, 70%) vs. 34% (-14%, 59%), both P < 0.05]. However, there were no statistically significant differences in the amount of fluid resuscitation, use of vasoactive drugs, and oxygenation index between the two groups during the resuscitation process. Multivariate Logistic regression analysis showed that body mass index (BMI) was independently correlated with 90-day mortality [odds ratio (OR) = 1.991, 95% confidence interval (95%CI) was 1.023-3.387, P = 0.043]. CONCLUSIONS There are no significant difference in plasma syndecan-1 level during fluid resuscitation of early sepsis and septic shock patients using balanced crystalloid fluid and balanced crystalloid fluid combined with albumin resuscitation, and there are no statistically significant differences in the impact on 28-day and 90-day prognosis, length of hospital stay, complications, and other aspects of the patients. However, compared to balanced crystalloid fluid, the combination of balanced crystalloid fluid and albumin for fluid resuscitation in sepsis patients has lower lactate level and better lactate clearance effect, but further validation is still needed through large-scale randomized controlled trials.
Humans ; Clinical Relevance ; Crystalloid Solutions/administration & dosage* ; Fluid Therapy/methods* ; Glycocalyx/metabolism* ; Isotonic Solutions/administration & dosage* ; Prospective Studies ; Resuscitation/methods* ; Sepsis/therapy* ; Shock, Septic/therapy* ; Syndecan-1/blood*

OBJECTIVE: To explore the protective effect of glycosaminoglycans (GAG) on vascular endothelium in patients with sepsis. METHODS: A prospective study was conducted on adult patients with sepsis admitted to the intensive care unit (ICU) of Hangzhou Normal University Affiliated Hospital from December 2022 to December 2023. Patients were randomly divided into conventional treatment group and GAG intervention group. Both groups were treated according to the 2021 Surviving Sepsis Campaign Guidelines. The GAG intervention group was additionally treated with GAG (2 mL of sulodexide intramuscular injection once daily for 7 days) on the basis of conventional treatment. Venous blood was collected from patients at 0, 6, 24, 48, 72 hours and 7 days after enrollment to detect serum vascular endothelial glycocalyx [heparan sulfate (HS) and syndecan-1 (SDC-1)], inflammatory markers [C-reactive protein (CRP), procalcitonin (PCT), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6)], and coagulation markers [prothrombin time (PT), activated partial thromboplastin time (APTT), antithrombin-III (AT-III), fibrinogen (Fib), D-Dimer], and to perform acute physiology and chronic health evaluation II (APACHE II), sequential organ failure assessment (SOFA), and International Society on Thrombosis and Haemostasis (ISTH) scores. The prognosis of patients (length of hospital stay, ICU and 28-day mortality) was observed. The receiver operator characteristic curve (ROC curve) was drawn to evaluate the value of HS in predicting the prognosis of sepsis patients, and the correlation between endothelial glycocalyx degradation products and various clinical indicators was analyzed. RESULTS: A total of 50 adult patients with sepsis meeting the inclusion criteria were enrolled, with 25 in the conventional treatment group and 25 in the GAG intervention group. In terms of degradation products of endothelial glycocalyx, compared to baseline, both groups showed an increasing trend in HS and SDC-1 levels post-treatment. However, the GAG intervention group exhibited significantly lower HS levels at 72 hours and 7 days, as well as lower SDC-1 levels at 6, 24, 48, 72 hours and 7 days compared to the conventional group. Among the surviving patients, the HS levels at 72 hours and SDC-1 levels at 6 hours of treatment in the GAG intervention group were significantly reduced compared to the conventional treatment group. In terms of severity score, compared with before treatment, the GAG intervention group showed a significant decrease in APACHE II, SOFA, and ISTH scores after 7 days of treatment. The SOFA scores of the GAG intervention group after 48 hours and 7 days of treatment were significantly lower than those of the conventional treatment group. In terms of inflammatory indicators, compared with before treatment, the GAG intervention group showed a significant decrease in IL-6 levels after 48 hours of treatment. With the prolongation of treatment time, the CRP levels of both groups of patients showed a significant downward trend, and at 7 days of treatment, the CRP level in the GAG intervention group was significantly lower than that in the conventional treatment group. In terms of coagulation function, with prolonged treatment time, PT and APTT of both groups of patients showed an increasing trend, while Fib showed a decreasing trend. The GAG intervention group showed a significant prolongation of PT after 72 hours of treatment compared to the conventional treatment group. In terms of prognosis, there were no statistically significant differences in ICU and 28-day mortality rates between the two groups. The GAG intervention group had significantly shorter hospital stays than the conventional treatment group. ROC curve analysis showed that HS, CRP, APTT, IL-6, APACHE II, SOFA, and ISTH scores were predictive factors for the prognosis of sepsis patients (all P < 0.05). Compared to a single indicator, the combined detection of multiple indicators has a higher value in predicting the prognosis of sepsis patients [area under the curve (AUC) = 0.911, 95% confidence interval (95%CI) was 0.817-1.000], with a sensitivity of 76.9% and a specificity of 91.9%. Correlation analysis showed that HS was significantly negatively correlated with Fib, PT, TNF-α, IL-6, and PCT (r values were -0.338, -0.396, -0.288, -0.319, and -0.340, all P < 0.05), while HS was significantly positively correlated with D-Dimer and CRP (r values were 0.347 and 0.354, both P < 0.05); SDC-1 was significantly negatively correlated with Fib, PT, APTT, TNF-α, IL-6, and ISTH scores (r values were -0.314, -0.294, -0.408, -0.353, -0.289, -0.287, all P < 0.05). CONCLUSIONS Early glycocalyx degradation can occur in sepsis patients. GAG have a protective effect on,the vascular endothelium, reducing the severity of sepsis and providing organ protection. HS, CRP, APTT, IL-6, APACHE II score, SOFA score, and ISTH score are independent predictive factors for the prognosis of sepsis patients. The combination of HS and the above indicators can significantly improve the accuracy of prediction.
Humans ; Sepsis/blood* ; Glycocalyx/drug effects* ; Glycosaminoglycans/pharmacology* ; Prospective Studies ; Endothelium, Vascular/metabolism* ; Syndecan-1/blood* ; Male ; Female ; C-Reactive Protein/metabolism* ; Interleukin-6/blood* ; Heparitin Sulfate/blood* ; Middle Aged ; Adult ; Tumor Necrosis Factor-alpha/blood* ; Procalcitonin/blood*

Triggering receptor expressed on myeloid cells 2 (TREM2)-mediated microglial phagocytosis is an energy-intensive process that plays a crucial role in amyloid beta (Aβ) clearance in Alzheimer's disease (AD). Energy metabolic reprogramming (EMR) in microglia induced by TREM2 presents therapeutic targets for cognitive impairment in AD. Jiawei Xionggui Decoction (JWXG) has demonstrated effectiveness in enhancing energy supply, protecting microglia, and mitigating cognitive impairment in APP/PS1 mice. However, the mechanism by which JWXG enhances Aβ phagocytosis through TREM2-mediated EMR in microglia remains unclear. This study investigates how JWXG facilitates microglial phagocytosis and alleviates cognitive deficits in AD through TREM2-mediated EMR. Microglial phagocytosis was evaluated through immunofluorescence staining in vitro and in vivo. The EMR level of microglia was assessed using high-performance liquid chromatography (HPLC) and enzyme-linked immunosorbent assay (ELISA) kits. The TREM2/protein kinase B (Akt)/mammalian target of rapamycin (mTOR)/hypoxia-inducible factor-1α (HIF-1α) signaling pathway was analyzed using Western blotting in BV₂ cells. TREM2^-/- BV₂ cells were utilized for reverse validation experiments. The Aβ burden, neuropathological features, and cognitive ability in APP/PS1 mice were evaluated using ELISA kits, immunohistochemistry (IHC), and the Morris water maze (MWM) test. JWXG enhanced both the phagocytosis of EMR disorder-BV₂ cells (EMRD-BV₂) and increased EMR levels. Notably, these effects were significantly reversed in TREM2^-/- BV₂ cells. JWXG elevated TREM2 expression, adenosine triphosphate (ATP) levels, and microglial phagocytosis in APP/PS1 mice. Additionally, JWXG reduced Aβ-burden, neuropathological lesions, and cognitive deficits in APP/PS1 mice. In conclusion, JWXG promoted TREM2-induced EMR and enhanced microglial phagocytosis, thereby reducing Aβ deposition, improving neuropathological lesions, and alleviating cognitive deficits.
Drugs, Chinese Herbal/pharmacology* ; Microglia/drug effects* ; Phagocytosis ; Cognitive Dysfunction/drug therapy* ; Metabolic Reprogramming ; Animals ; Mice ; Cell Line ; Receptors, Immunologic/metabolism* ; Membrane Glycoproteins/metabolism* ; Signal Transduction ; Amyloid beta-Peptides/metabolism* ; Energy Metabolism

OBJECTIVE: To reveal the effects and potential mechanisms by which synaptic vesicle glycoprotein 2A (SV2A) influences the distribution of amyloid precursor protein (APP) in the trans-Golgi network (TGN), endolysosomal system, and cell membranes and to reveal the effects of SV2A on APP amyloid degradation. METHODS: Colocalization analysis of APP with specific tagged proteins in the TGN, ensolysosomal system, and cell membrane was performed to explore the effects of SV2A on the intracellular transport of APP. APP, β-site amyloid precursor protein cleaving enzyme 1 (BACE1) expressions, and APP cleavage products levels were investigated to observe the effects of SV2A on APP amyloidogenic processing. RESULTS: APP localization was reduced in the TGN, early endosomes, late endosomes, and lysosomes, whereas it was increased in the recycling endosomes and cell membrane of SV2A-overexpressed neurons. Moreover, Arl5b (ADP-ribosylation factor 5b), a protein responsible for transporting APP from the TGN to early endosomes, was upregulated by SV2A. SV2A overexpression also decreased APP transport from the cell membrane to early endosomes by downregulating APP endocytosis. In addition, products of APP amyloid degradation, including sAPPβ, Aβ _1-42, and Aβ _1-40, were decreased in SV2A-overexpressed cells. CONCLUSION These results demonstrated that SV2A promotes APP transport from the TGN to early endosomes by upregulating Arl5b and promoting APP transport from early endosomes to recycling endosomes-cell membrane pathway, which slows APP amyloid degradation.
Amyloid beta-Protein Precursor/genetics* ; Membrane Glycoproteins/genetics* ; Animals ; Protein Transport ; Nerve Tissue Proteins/genetics* ; Humans ; Mice ; Endosomes/metabolism* ; trans-Golgi Network/metabolism*

OBJECTIVES: The aim of this study is to determine the effect of cannabinoid receptor (CB) 2 inhibitor on desmoglein 3 (DSG3) expression in HaCaT cells co-cultured with pemphigus serum. METHODS: Immunohistochemical staining was used to compare CB expression in pemphigus patients and normal individuals. Enzyme-linked immunosorbent assay (ELISA) was employed to quantify the concentration of CB2 in the serum of pemphigus patients and normal individuals. A correlation analysis was performed to examine the relationship between the serum CB2 and DSG of pemphigus patients. The CCK-8 assay was used to evaluate the inhibitory effect of AM630 on HaCaT cells, and the half-maximal inhibitory concentration (IC₅₀) value was utilized to determine the experimental concentration. Serum from normal individuals (negative control group) and pemphigus patients (pemphigus group) was co-cultured with HaCaT cells at a 1∶1 ratio. HaCaT cells cultured in complete medium were used as the control group. HaCaT cells in the pemphigus group treated with AM630 were employed as the AM630 group. Real-time polymerase chain reaction (PCR) and Western blot were conducted to assess the expression levels of CB2, DSG3, and β-catenin. Cell dissociation experiments were conducted to evaluate the effect of AM630 on the adhesion of HaCaT cells. RESULTS: Immunohistochemistry revealed significant differences in CB2 expression between pemphigus and normal mucosa (P<0.000 1), but no difference was found in CB1 expression. ELISA analysis revealed a statistically significant difference in the expression levels of CB2 in the serum between normal individuals and pemphigus patients (P<0.001). The expression of CB2 in the serum of pemphigus patients exhibited a significant positive correlation with that of DSG3 (r=0.831, P=0.003). The CCK-8 assay indicated that the IC₅₀ of AM630 on HaCaT cells was 0.55 μmol/L. Real-time PCR and Western blot showed that the expression levels of CB2 and DSG3 increased in the pemphigus group, while the expression level of β-catenin decreased compared with that in the AM630 groups (P<0.05). CONCLUSIONS CB2 is highly expressed in oral mucosal pemphigus. AM630 inhibits overexpression of CB2 and DSG3 and underexpression of β-catenin levels, which can provide new therapeutic targets for pemphigus.
Humans ; Pemphigus/pathology* ; Receptor, Cannabinoid, CB2/metabolism* ; Desmoglein 3/metabolism* ; Acantholysis/metabolism* ; Mouth Mucosa/pathology* ; HaCaT Cells ; Coculture Techniques ; beta Catenin/metabolism*

OBJECTIVE: To investigate a case of antibodies against high-frequency erythrocyte antigens and elucidate the genetic mechanism underlying the blood group. METHODS: A Lan-negative patient referred to the Zhejiang Blood Center by Quzhou Hospital of Traditional Chinese Medicine in August 2016 was selected as the study subject. A retrospective study was conducted to collect the proband's clinical data. The proband's erythrocyte antigens and unexpected serum antibodies were identified using tube saline and microcolumn agglutination anti-human globulin methods. Antibody specificity was determined by treating erythrocytes with 7 enzymes and 2 chemical reducing agents. Genomic DNA was extracted from the proband's blood sample for whole genome sequencing (WGS) and erythrocyte blood group gene analysis, with validation by Sanger sequencing. Multiple bioinformatics tools were used to analyze the pathogenicity of the variant. The rare blood group and unexpected antibody specificity were comprehensively determined based on the results of serological and genetic testing. This study has been approved by the Zhejiang Provincial Blood Center Medical Ethics Committee(Ethics No.20190201). RESULTS: The proband was a 91-year-old Han Chinese male with prostatitis, cystitis, and malnutrition in conjunct with emaciation. He had a history of multiple erythrocyte transfusions without observable adverse reactions. Prior to the most recent transfusion, major crossmatch agglutination was observed, which prompted antibody identification. Antibodies against high-frequency antigens were detected in the proband's serum, with enzyme and reducing agent treatments ruling out antibody specificities associated with 17 blood group systems, e.g., MNS, LU, KEL. WGS analysis identified 4 525 SNPs and 1 046 INDEL variants among erythrocyte blood group genes. Further screening revealed that the proband had a rare blood group due to a homozygous rs755723161 variant. This variant in the ABCB6 gene (c.459delC) has led to a frameshifting mutation (p.Trp154GlyfsTer96), resulting in the Lan-negative rare blood group with a high-frequency antigen deficiency and the production of IgG anti-Lan antibodies in the serum. CONCLUSION This study has identified anti-Lan alloantibodies in a Lan-negative patient and, for the first time, elucidated the ABCB6 gene variant underlying the Lan-negative rare blood group in the Chinese population.
Humans ; Male ; Blood Group Antigens/immunology* ; Aged, 80 and over ; Retrospective Studies ; ATP-Binding Cassette Transporters

OBJECTIVE: To explore the correlation between clinical manifestations and genetic variations in six Chinese Stargardt disease pedigrees. METHODS: Six Stargardt disease pedigrees due to ABCA4 gene variants that visited Shanxi Eye Hospital from June 2021 June 2023 were selected as the study subjects. A retrospective study method was used to collect the clinical and family history data of all members of these pedigrees. Peripheral venous blood samples of the examinees were collected, and genomic DNA was extracted for trio-WES. Candidate variants of the ABCA4 gene were verified by family Sanger sequencing. According to the "Standards and Guidelines for the Classification of Sequence Variants" (hereinafter referred to as the "ACMG Guidelines") formulated by American College of Medical Genetics and Genomics (ACMG), the variant sites of the ABCA4 gene were classified for pathogenicity. This study has been approved by the Medical Ethics Committee of Shanxi Eye Hospital (Ethics No. SXYYLL-20200620). RESULTS: From June 2021 to June 2023, 7 patients (patient 1 to 7) from families with Stargardt disease with ABCA4 variants were selected as the study subjects. The age of the patients was between 7 to 53 years old, and the age of onset was between their 6 to 15 years old. All patients had exhibited moderate-to-severe visual impairment with macular atrophy, and yellow white spots were seen in all patients except patient II2 in family 5. Optical coherence tomography (OCT) results showed that all patients' macular fovea was significantly thinner, with IS/OS or ellipsoid zone disappeared. Autofluorescence showed low autofluorescence in the macula, and abnormalities dot autofluorescence in the paramacular and periphery retina. ERG grouping classified three pedigrees as Group 3, two as Group 1, and one as Group 2. Genetic analysis results showed that all pedigrees had autosomal recessive inheritance, five had compound heterozygous variants in the ABCA4, and one had homozygous variants. In total 11 pathogenic mutations were detected in the ABCA4 gene, of which 3 were found for the first time, including p.Glu1704Gly, p.Gly1965Glu and p.Ser1531Phe. Patients carrying nonsense or frameshift mutations include patient 1 (family 1, II1), patient 2 (family 1, II2), patient 4 (family 3, II1), patient 6 (family 5, II2), and patient 7 (family 6, II1), whose clinical manifestations are more severe than those of patient 3 (family 2, II2) and patient 5 (family 4, II1), whom carried missense mutations in terms of best corrected visual acuity (BCVA) damage. CONCLUSION The ABCA4 gene variations may be the genetic cause of the Stargardt disease in this study, and the discovery of the ABCA4 gene p.Glu1704Gly, p.Gly1965Glu, p.Ser1531Phe variants has enriched the mutational spectrum of Stargardt disease.
Adolescent ; Adult ; Child ; Female ; Humans ; Male ; Middle Aged ; Young Adult ; ATP-Binding Cassette Transporters/genetics* ; China ; Genetic Variation ; Macular Degeneration/congenital* ; Mutation ; Pedigree ; Retrospective Studies ; Stargardt Disease/genetics* ; East Asian People/genetics*

OBJECTIVE: To investigate the clinical features and pathogenesis of a child with Stargardt disease caused by variants of ABCA4 gene. METHODS: A child presented at Shenzhen Eye Hospital between September 5, 2020, and April 3, 2023 was selected as the study subject. Clinical data of the child were collected. Whole exome sequencing was performed on peripheral blood samples from the child and his parents. Candidate variants were validated by Sanger sequencing and bioinformatic analysis. This study was approved by the Medical Ethics Committee of Shenzhen Eye Hospital (Ethics No.: 2022KYPJ072). RESULTS: The child was a 10-year-old male presenting with uncorrected visual acuity of 0.1 in both eyes without improvement with refractive correction. Fundus photography showed diffusely distributed yellow-white flecks in the macular region. FAF revealing central hypofluorescence surrounded by a hyperfluorescent ring, and OCT demonstrating significant foveal thinning (right eye: 45 μm; left eye: 50 μm) with ellipsoid zone disruption. Whole exome sequencing and Sanger sequencing revealed that the child has harbored compound heterozygous variants of the ABCA4 gene, namely c.2384G>T (p.Gly795Val) and c.2903G>A (p.Arg968Glu), which were inherited from his phenotypically normal parents and consistent with an autosomal recessive inheritance. This specific combination of the variants was previously unreported. According to the guidelines from the American College of Medical Genetics and Genomics (ACMG) guidelines, both variants were classified as likely pathogenic (PM2_Supporting+PM3+PP3+PP4; PM1+PM2_Supporting+PP3+PP4). CONCLUSION The novel compound heterozygous variants of the ABCA4 gene probably underlay the genetic etiology of Stargardt disease type 1 in this child. Above finding has expanded the mutational spectrum of the ABCA4 gene among the Chinese population and provided further evidence for understanding the genetic heterogeneity and genotype-phenotype correlation of the Stargardt disease.
Humans ; Male ; Child ; ATP-Binding Cassette Transporters/genetics* ; Stargardt Disease/genetics* ; Heterozygote ; Mutation ; Exome Sequencing ; Macular Degeneration/congenital*