Objective Currently, there is no commercially available quantitative detection kit for the main Felis domestic allergen (Fel d 1) in China. To establish a rapid detection method for Fel d 1, this study aims to prepare monoclonal antibodies against Fel d 1 protein. Methods The codon preference of Escherichia coli was utilized to optimize and synthesize the Fel d 1 gene. The prokaryotic expression plasmid pET-28a-Fel d 1 was constructed and used to express and purify the recombinant Fel d 1 protein. Subsequently, the recombinant protein was immunized into BALB/c mice and monoclonal antibodies (mAbs) were prepared by the hybridoma technique. An indirect ELISA was established using the recombinant Fel d 1 as the coating antigen, and hybridoma cell lines were screened for positive clones. The specificity and antigenic epitopes of the mAbs were confirmed by Western blot analysis. Finally, the selected hybridoma cells were injected into the peritoneal cavities of BALB/c mice for large-scale monoclonal antibody production. Results The recombinant plasmid pET-28a-Fel d 1 was successfully constructed, and soluble Fel d 1 protein was obtained after optimizing the expression conditions. Western blot and antibody titer assays confirmed the successful isolation of two hybridoma cell lines, 7D11 and 5H4, which stably secreted mAbs specific to Fel d 1. Antibody characterization revealed that the 5H4 mAb was of the IgG2a subtype and could recognize the amino acid region 105-163 of Fel d 1, while the 7D11 mAb was the IgG1 subtype and could recognize the amino acid region 1-59. Conclusion The high-purity recombinant Fel d 1 protein produced in this study provides a promising alternative for clinical immunotherapy of cat allergies. Furthermore, the monoclonal antibody prepared in this experiment lays a material foundation for the in-depth study of the biological function of Fel d 1 and the development of ELISA detection.
Animals ; Antibodies, Monoclonal/biosynthesis* ; Mice, Inbred BALB C ; Cats ; Mice ; Allergens/genetics* ; Glycoproteins/genetics* ; Enzyme-Linked Immunosorbent Assay ; Hybridomas/immunology* ; Recombinant Proteins/genetics* ; Female ; Antibody Specificity

Objective·To investigate the changes in transcriptome and chromatin accessibility during the differentiation of human embryonic stem cells(hESCs)into neural progenitor cells(NPCs)using in vitro differentiation models and high-throughput multi-omics sequencing technologies.Methods·hESCs were first induced to differentiate into NPCs in vitro using the embryoid body formation method,and cells at both stages were collected.The cell phenotypes were identified by reverse transcription-quantitative real-time PCR(RT-qPCR)and immunofluorescence(IF)staining.Transcriptome sequencing(RNA-seq)was conducted to detect and analyze the differentially expressed genes(DEGs)between hESCs and NPCs.The assay for transposase-accessible chromatin with high-throughput sequencing(ATAC-seq)was employed to assess chromatin accessibility changes between hESCs and NPCs.Motif enrichment analysis was performed on differentially accessible chromatin regions to discover potential regulatory transcription factors.Finally,an integrated analysis of RNA-seq and ATAC-seq data and the protein-protein interaction(PPI)network were performed to identify key genes and regulatory pathways involved in the early stages of neural differentiation in vitro.Results·Both RT-qPCR and IF results indicated that the expression levels of pluripotency markers(NANOG and POU5F1)were high at the hESC stage but significantly decreased at the NPC stage,while early neural differentiation markers(PAX6,SOX1,and NES)were minimally expressed at the hESC stage but markedly upregulated at the NPC stage.RNA-seq analysis revealed that compared to the hESC stage,there were 5 597 genes upregulated and 3 654 genes downregulated at the NPC stage.Gene function enrichment analysis showed that the upregulated genes at the NPC stage were enriched in the functions related to neural development.ATAC-seq analysis demonstrated a total of 27 491 genomic regions had significant changes in chromatin accessibility during the differentiation from hESC to NPC,with 12 381 regions showing increased accessibility and 15 110 regions showing decreased accessibility.Motif enrichment analysis revealed that transcription factor genes such as DLX1 and LHX2 might play an important role in the differentiation process from hESCs into NPCs.Integrated analysis of RNA-seq and ATAC-seq data revealed that overlapping genes with high expression at the NPC stage were mainly enriched in axon guidance,forebrain development,and neuron migration.After neural differentiation,the expression levels of CTNND2 and LHX2 genes increased,and the chromatin accessibility of related genomic regions also increased.PPI network analysis indentified candidate downstream genes including PRKACA,CDH2,and ERBB4.Conclusion·The in vitro differentiation model of hESCs combined with high-throughput multi-omics sequencing technologies can be used to depict the changes in transcriptome and chromatin accessibility during the differentiation of hESCs into NPCs.In this process,the expression levels of genes related to axon guidance,forebrain development,and neuronal migration pathways increase and related chromatin accessibility is enhanced.

Objective·To investigate the changes in transcriptome and chromatin accessibility during the differentiation of human embryonic stem cells(hESCs)into neural progenitor cells(NPCs)using in vitro differentiation models and high-throughput multi-omics sequencing technologies.Methods·hESCs were first induced to differentiate into NPCs in vitro using the embryoid body formation method,and cells at both stages were collected.The cell phenotypes were identified by reverse transcription-quantitative real-time PCR(RT-qPCR)and immunofluorescence(IF)staining.Transcriptome sequencing(RNA-seq)was conducted to detect and analyze the differentially expressed genes(DEGs)between hESCs and NPCs.The assay for transposase-accessible chromatin with high-throughput sequencing(ATAC-seq)was employed to assess chromatin accessibility changes between hESCs and NPCs.Motif enrichment analysis was performed on differentially accessible chromatin regions to discover potential regulatory transcription factors.Finally,an integrated analysis of RNA-seq and ATAC-seq data and the protein-protein interaction(PPI)network were performed to identify key genes and regulatory pathways involved in the early stages of neural differentiation in vitro.Results·Both RT-qPCR and IF results indicated that the expression levels of pluripotency markers(NANOG and POU5F1)were high at the hESC stage but significantly decreased at the NPC stage,while early neural differentiation markers(PAX6,SOX1,and NES)were minimally expressed at the hESC stage but markedly upregulated at the NPC stage.RNA-seq analysis revealed that compared to the hESC stage,there were 5 597 genes upregulated and 3 654 genes downregulated at the NPC stage.Gene function enrichment analysis showed that the upregulated genes at the NPC stage were enriched in the functions related to neural development.ATAC-seq analysis demonstrated a total of 27 491 genomic regions had significant changes in chromatin accessibility during the differentiation from hESC to NPC,with 12 381 regions showing increased accessibility and 15 110 regions showing decreased accessibility.Motif enrichment analysis revealed that transcription factor genes such as DLX1 and LHX2 might play an important role in the differentiation process from hESCs into NPCs.Integrated analysis of RNA-seq and ATAC-seq data revealed that overlapping genes with high expression at the NPC stage were mainly enriched in axon guidance,forebrain development,and neuron migration.After neural differentiation,the expression levels of CTNND2 and LHX2 genes increased,and the chromatin accessibility of related genomic regions also increased.PPI network analysis indentified candidate downstream genes including PRKACA,CDH2,and ERBB4.Conclusion·The in vitro differentiation model of hESCs combined with high-throughput multi-omics sequencing technologies can be used to depict the changes in transcriptome and chromatin accessibility during the differentiation of hESCs into NPCs.In this process,the expression levels of genes related to axon guidance,forebrain development,and neuronal migration pathways increase and related chromatin accessibility is enhanced.

Objective:To analyze the clinical effect of hyaluronidase injection through the facial artery in the treatment of vascular embolism such as skin ulceration and necrosis after cosmetic injection.Methods:Hyaluronidase was injected through facial artery in 13 patients who were diagnosed with vascular embolism after facial injection from January 2019 to May 2020. The facial artery was punctured with 22-gauge arterial blood collection needle or 19/23-gauge disposable venous infusion needle. The angle between the needle body and the skin varies depending on the patients’ weight, ranged 30°-45°. The needle was advanced slowly and pushed forward by 2-3 mm when blood backflow appeared in the needle core. After confirming the successful puncture of the facial artery, 0.5-1.5 ml hyaluronidase was slowly injected into the facial artery. The time of skin relaxation, tenderness relief, ulcer healing and wound recovery were observed. The pigmentation was observed and the Vancouver Scar Scale (VSS) was used to score the scars after 3-12 months.Results:A toal of 13 patients with vascular complications of hyaluronidase filler were retrospectively reviewed. The patients were 18-45-year-old(mean age, 35 years) and received hyaluronidase filler at private clinics. There were 12 women and 1 man. The time from onset to visit was 14 h to 4 d, with an average time of 2.5 d. Hyaluronidase was most commonly injected into the nasolabial folds (54%, 7 of 13). The second-ranked area is the nasalroot (23%, 3 of 13). These patients had skin swelling, necrosis, ecchymosis or black scabs during or after hyaluronidase injection. Some patients showed skin lesions combined with oral ulcer. After percutaneous facial arterial hyaluronidase injection, the local skin tissue injuries of the 13 patients were improved in time. The time of skin relaxation was (0.77±0.25) d, the time of tenderness relief was (1.23±0.64) d, the time of ulcer healing was (3.14±0.64) d and the time of wound recovery was (5.85±0.86) d. Patients were followed up for 3-12 months, with an average of 7 months. One patient had slight scar (VSS score of 1), two patients had only mild pigmentation (VSS score of 0), and the other ten patients had no scar and pigmentation (VSS score of 0).Conclusions:It is effective to improve local microcirculation and reduce skin tissue injury after percutaneous facial artery hyaluronidase injection in the treatment of skin injury caused by facial filler injection.

Objective:To analyze the clinical effect of hyaluronidase injection through the facial artery in the treatment of vascular embolism such as skin ulceration and necrosis after cosmetic injection.Methods:Hyaluronidase was injected through facial artery in 13 patients who were diagnosed with vascular embolism after facial injection from January 2019 to May 2020. The facial artery was punctured with 22-gauge arterial blood collection needle or 19/23-gauge disposable venous infusion needle. The angle between the needle body and the skin varies depending on the patients’ weight, ranged 30°-45°. The needle was advanced slowly and pushed forward by 2-3 mm when blood backflow appeared in the needle core. After confirming the successful puncture of the facial artery, 0.5-1.5 ml hyaluronidase was slowly injected into the facial artery. The time of skin relaxation, tenderness relief, ulcer healing and wound recovery were observed. The pigmentation was observed and the Vancouver Scar Scale (VSS) was used to score the scars after 3-12 months.Results:A toal of 13 patients with vascular complications of hyaluronidase filler were retrospectively reviewed. The patients were 18-45-year-old(mean age, 35 years) and received hyaluronidase filler at private clinics. There were 12 women and 1 man. The time from onset to visit was 14 h to 4 d, with an average time of 2.5 d. Hyaluronidase was most commonly injected into the nasolabial folds (54%, 7 of 13). The second-ranked area is the nasalroot (23%, 3 of 13). These patients had skin swelling, necrosis, ecchymosis or black scabs during or after hyaluronidase injection. Some patients showed skin lesions combined with oral ulcer. After percutaneous facial arterial hyaluronidase injection, the local skin tissue injuries of the 13 patients were improved in time. The time of skin relaxation was (0.77±0.25) d, the time of tenderness relief was (1.23±0.64) d, the time of ulcer healing was (3.14±0.64) d and the time of wound recovery was (5.85±0.86) d. Patients were followed up for 3-12 months, with an average of 7 months. One patient had slight scar (VSS score of 1), two patients had only mild pigmentation (VSS score of 0), and the other ten patients had no scar and pigmentation (VSS score of 0).Conclusions:It is effective to improve local microcirculation and reduce skin tissue injury after percutaneous facial artery hyaluronidase injection in the treatment of skin injury caused by facial filler injection.