Objective:To investigate alterations in the immune lineage of T-cell large granular lymphocytic leukemia (T-LGLL) at the single-cell transcriptome level and to elucidate its pathogenic mechanisms.Methods:Peripheral blood samples were collected from 5 T-LGLL patients before and after treatment (from June 2019 to December 2020) and 3 healthy controls at the Institute of Hematology & Blood Diseases Hospital, CAMS & PUMC. Single-cell transcriptome sequencing libraries were prepared and sequenced using 10× Genomics technology. Differentially expressed genes in immune cells were compared between patients and healthy donors, followed by pathway enrichment analyses.Results:Profiling 67,237 immune cells revealed that, in T-LGLL: 1) Effector CD8+ T cells exhibited increased numbers, enhanced cytotoxicity, and greater proliferative capacity. Following effective immunosuppressive therapy, both the proliferative capacity and effector functions of these cells significantly decreased ( P<0.05). 2) The proportion of regulatory T (Treg) cells was reduced, accompanied by increased apoptosis. After effective immunosuppressive therapy leading to remission, Treg cell proportions increased, and apoptotic pathways were downregulated ( P<0.05). 3) Antigen-presenting cells (APCs) showed enhanced functionality. Monocytes and dendritic cells were enriched in antigen synthesis and presentation pathways, while B cells displayed increased antigen-binding capacity and were enriched in pathways related to T-cell activation ( P<0.05). 4) Natural killer (NK) cells exhibited attenuated cytotoxic function but demonstrated an enhanced regulatory capacity over T cells ( P<0.05) . Conclusions:T-LGLL patients present a characteristic immunological profile marked by an imbalance in immune homeostasis. This profile includes abnormal activation and expansion of effector CD8 + T cells, and a reduction in Treg cell numbers accompanied by functional impairment. Furthermore, APCs and NK cells were found to positively regulate T-lymphocyte activation, differentiation, and proliferation.

: Bacteroides, as one of the most abundant and diverse genera in the human gut, is regarded as a window into the study of gut microbiota-host interactions. Currently, CRISPR/Cas-based gene editing systems targeting Bacteroides have been widely applied, while the large size of Cas nucleases limits their potential application scenarios (such as in situ gut Bacteroides editing based on phage delivery). Therefore, this study aims to develop a compact and highly efficient genetic editing tool in Bacteroides., We developed a miniaturized CRISPR/Cas gene editing system for human gut Bacteroides. First, the editing capabilities of different miniaturized CRISPR/Cas systems, including AsCas12f, CasΦ2, and ISDge10, were evaluated in Bacteroides fragilis. Subsequently, the editing capability of AsCas12f was assessed across various Bacteroides species, and the size of this system was further optimized. The results demonstrated that the CRISPR/AsCas12f genome editing system exhibited the highest editing efficiency in B. fragilis. The CRISPR/AsCas12f system achieved efficient genome editing in B. fragilis, Bacteroides thetaiotaomicron, and Phocaeicola vulgatus. Furthermore, with a repair template of 500 bp homologous arms, the editing efficiency remained as high as 94.7%. In conclusion, CRISPR/AsCas12f can serve as a chassis tool enzyme for the development of Bacteroides-based miniature gene editors and derivative technologies, laying a foundation for the further development of gene editing technology for Bacteroides.
CRISPR-Cas Systems/genetics* ; Gene Editing/methods* ; Bacteroides/genetics* ; Humans ; Gastrointestinal Microbiome/genetics* ; Bacteroides fragilis/genetics*

Objective:To investigate alterations in the immune lineage of T-cell large granular lymphocytic leukemia (T-LGLL) at the single-cell transcriptome level and to elucidate its pathogenic mechanisms.Methods:Peripheral blood samples were collected from 5 T-LGLL patients before and after treatment (from June 2019 to December 2020) and 3 healthy controls at the Institute of Hematology & Blood Diseases Hospital, CAMS & PUMC. Single-cell transcriptome sequencing libraries were prepared and sequenced using 10× Genomics technology. Differentially expressed genes in immune cells were compared between patients and healthy donors, followed by pathway enrichment analyses.Results:Profiling 67,237 immune cells revealed that, in T-LGLL: 1) Effector CD8+ T cells exhibited increased numbers, enhanced cytotoxicity, and greater proliferative capacity. Following effective immunosuppressive therapy, both the proliferative capacity and effector functions of these cells significantly decreased ( P<0.05). 2) The proportion of regulatory T (Treg) cells was reduced, accompanied by increased apoptosis. After effective immunosuppressive therapy leading to remission, Treg cell proportions increased, and apoptotic pathways were downregulated ( P<0.05). 3) Antigen-presenting cells (APCs) showed enhanced functionality. Monocytes and dendritic cells were enriched in antigen synthesis and presentation pathways, while B cells displayed increased antigen-binding capacity and were enriched in pathways related to T-cell activation ( P<0.05). 4) Natural killer (NK) cells exhibited attenuated cytotoxic function but demonstrated an enhanced regulatory capacity over T cells ( P<0.05) . Conclusions:T-LGLL patients present a characteristic immunological profile marked by an imbalance in immune homeostasis. This profile includes abnormal activation and expansion of effector CD8 + T cells, and a reduction in Treg cell numbers accompanied by functional impairment. Furthermore, APCs and NK cells were found to positively regulate T-lymphocyte activation, differentiation, and proliferation.

Objective:To explore the relevancy between the uridine diphosphate-glucuronylgly-cosyltransferase 1A1 (UGT1A1) gene mutation and the phenotype of indirect hyperbilirubinemia in children.Methods:Sixteen cases with indirect hyperbilirubinemia who visited the Department of Gastroenterology, Children's Hospital of Nanjing Medical University from July 2013 to November 2019 were retrospectively analyzed and were divided into Gilbert syndrome (GS), Crigler-Najjar syndrome type II (CNS-II), and indirect hyperbilirubinemia groups unexplained by UGT1A1 gene mutations. The differences in gene mutation site information and general clinical data were compared. The association between gene mutation spectrum and bilirubin level was explored by t-test analysis.Results:Ten of the sixteen cases with indirect hyperbilirubinemia had GS, three had CNS-II, and three had indirect hyperbilirubinemia unexplained by UGT1A1 gene mutations. A total of six mutation types were detected, of which c.211G?>?A accounted for 37.5% (6/16), c.1456T?>?G accounted for 62.5% (10/16), and TATA accounted for 37.5% (6/16), respectively. Compared with the GS group, the CNS group had early disease onset incidence, high serum total bilirubin ( t ?=?5.539, P ??0.05) and age of onset ( t ?=?0.3611, P ?>?0.05) between the two groups. There was no significant correlation between the number of UGT1A1 gene mutations and serum bilirubin levels. Children with c.1456T?>?G homozygous mutations had the highest serum bilirubin levels. Conclusion:The common pathogenic variants of the UGT1A1 gene sequence are c.1456T?>?G, c.211G?>?A, and TATA, indicating that these site mutations are related to the occurrence of indirect hyperbilirubinemia and have important guiding significance for the etiological analysis of indirect hyperbilirubinemia in children.