Cyclic GMP-AMP synthase (cGAS), a pivotal molecule in innate immunity, has emerged as a keypoint in interdisciplinary research at the intersection of basic immunology and tumor biology. As a cytosolic nucleic acid sensor, cGAS is primarily characterized by its capacity to recognize double-stranded DNA (dsDNA) in the cytosol. Upon binding to dsDNA, cGAS undergoes a conformational change that promotes its dimerization and subsequent enzymatic activation. Once activated, it catalyzes the synthesis of the second messenger 2',3'-cGAMP from ATP and GTP. cGAMP then binds to the adaptor protein STING, which resides on the endoplasmic reticulum (ER) membrane. The binding process triggers STING to traffic from the ER to the Golgi apparatus, where it is phosphorylated by the kinase TBK1. Phosphorylated STING serves as a docking site for the transcription factor IRF3, facilitating its phosphorylation by TBK1. Once phosphorylated, IRF3 forms dimers and translocates to the nucleus, where it drives the expression of type I interferons and pro-inflammatory cytokines, initiating a potent antimicrobial state. The DNA-sensing mechanism of cGAS is inherently non-selective regarding the origin of its ligand. It readily detects exogenous DNA from invading pathogens, thereby playing an indispensable role in host defense against microbial infections. However, this same mechanism also enables cGAS to recognize self-DNA that leaks from the nucleus or mitochondria into the cytosol under various cellular stress conditions. While critical for immunity, the recognition of self-dsDNA by cGAS can disrupt cellular homeostasis and trigger aberrant inflammatory responses. The loss of self-tolerance can precipitate or exacerbate the pathogenesis of autoimmune disorders such as systemic lupus erythematosus (SLE) and Aicardi-Goutières syndrome (AGS), highlighting the dual role of cGAS as both a sentinel for infection and a potential driver of autoimmune pathology. Notably, the subcellular localization of cGAS is not still. Increasing recent researches have revealed that cGAS is also abundant within the nucleus, challenging the traditional view of it solely as a cytosolic nucleic acid sensor. Within the nucleus, cGAS exhibits non-canonical functions that are distinct from its canonical immunological role. First, cGAS exists in a state of stringent immunological silence in the nucleus, with mechanisms involving its competitive binding to histones and its post-translational modifications which block the activation of cGAS enzymatic activity, thus, effectively preventing it from mounting an autoimmune attack on genomic DNA. Second, cGAS plays a critical role in maintaining genomic stability. Upon DNA damage, cGAS is rapidly recruited to the lesion site and participates in the DNA damage repair process. Moreover, under conditions of DNA replication stress, cGAS contributes to the stabilization of replication forks, preventing the cell from entering a state of uncontrolled hyper-replication. Consequently, in light of the dual role of cGAS in both immune regulation and tumor development, the development of small-molecule drugs targeting cGAS holds significant therapeutic promise. This review summarizes the structural characteristics of cGAS and its canonical function as a pattern recognition receptor in the cytosol, including the types of pathogens it recognizes and the autoimmune responses resulting from erroneous recognition of self-DNA. It then focuses on its emerging non-canonical functions within the nucleus, detailing its nucleocytoplasmic shuttling, the mechanisms underlying its nuclear immune quiescence, and its role in mediating DNA damage repair and replication fork stabilization. Finally, the review discusses the progress and application prospects of small-molecule drugs targeting cGAS for the treatment of autoimmune diseases and cancer.

Cyclic GMP-AMP synthase (cGAS), a pivotal molecule in innate immunity, has emerged as a keypoint in interdisciplinary research at the intersection of basic immunology and tumor biology. As a cytosolic nucleic acid sensor, cGAS is primarily characterized by its capacity to recognize double-stranded DNA (dsDNA) in the cytosol. Upon binding to dsDNA, cGAS undergoes a conformational change that promotes its dimerization and subsequent enzymatic activation. Once activated, it catalyzes the synthesis of the second messenger 2',3'-cGAMP from ATP and GTP. cGAMP then binds to the adaptor protein STING, which resides on the endoplasmic reticulum (ER) membrane. The binding process triggers STING to traffic from the ER to the Golgi apparatus, where it is phosphorylated by the kinase TBK1. Phosphorylated STING serves as a docking site for the transcription factor IRF3, facilitating its phosphorylation by TBK1. Once phosphorylated, IRF3 forms dimers and translocates to the nucleus, where it drives the expression of type I interferons and pro-inflammatory cytokines, initiating a potent antimicrobial state. The DNA-sensing mechanism of cGAS is inherently non-selective regarding the origin of its ligand. It readily detects exogenous DNA from invading pathogens, thereby playing an indispensable role in host defense against microbial infections. However, this same mechanism also enables cGAS to recognize self-DNA that leaks from the nucleus or mitochondria into the cytosol under various cellular stress conditions. While critical for immunity, the recognition of self-dsDNA by cGAS can disrupt cellular homeostasis and trigger aberrant inflammatory responses. The loss of self-tolerance can precipitate or exacerbate the pathogenesis of autoimmune disorders such as systemic lupus erythematosus (SLE) and Aicardi-Goutières syndrome (AGS), highlighting the dual role of cGAS as both a sentinel for infection and a potential driver of autoimmune pathology. Notably, the subcellular localization of cGAS is not still. Increasing recent researches have revealed that cGAS is also abundant within the nucleus, challenging the traditional view of it solely as a cytosolic nucleic acid sensor. Within the nucleus, cGAS exhibits non-canonical functions that are distinct from its canonical immunological role. First, cGAS exists in a state of stringent immunological silence in the nucleus, with mechanisms involving its competitive binding to histones and its post-translational modifications which block the activation of cGAS enzymatic activity, thus, effectively preventing it from mounting an autoimmune attack on genomic DNA. Second, cGAS plays a critical role in maintaining genomic stability. Upon DNA damage, cGAS is rapidly recruited to the lesion site and participates in the DNA damage repair process. Moreover, under conditions of DNA replication stress, cGAS contributes to the stabilization of replication forks, preventing the cell from entering a state of uncontrolled hyper-replication. Consequently, in light of the dual role of cGAS in both immune regulation and tumor development, the development of small-molecule drugs targeting cGAS holds significant therapeutic promise. This review summarizes the structural characteristics of cGAS and its canonical function as a pattern recognition receptor in the cytosol, including the types of pathogens it recognizes and the autoimmune responses resulting from erroneous recognition of self-DNA. It then focuses on its emerging non-canonical functions within the nucleus, detailing its nucleocytoplasmic shuttling, the mechanisms underlying its nuclear immune quiescence, and its role in mediating DNA damage repair and replication fork stabilization. Finally, the review discusses the progress and application prospects of small-molecule drugs targeting cGAS for the treatment of autoimmune diseases and cancer.

The ventral anterior (VA) nucleus of the thalamus is a major target of the basal ganglia and is closely associated with the pathogenesis of Parkinson's disease (PD). Notably, the VA receives direct innervation from the hypothalamic histaminergic system. However, its role in PD remains unknown. Here, we assessed the contribution of histamine to VA neuronal activity and PD motor deficits. Functional magnetic resonance imaging showed reduced VA activity in PD patients. Optogenetic activation of VA neurons or histaminergic afferents significantly alleviated motor deficits in 6-OHDA-induced PD rats. Furthermore, histamine excited VA neurons via H1 and H2 receptors and their coupled hyperpolarization-activated cyclic nucleotide-gated channels, inward-rectifier K⁺ channels, or Ca²⁺-activated K⁺ channels. These results demonstrate that histaminergic afferents actively compensate for Parkinsonian motor deficits by biasing VA activity. These findings suggest that targeting VA histamine receptors and downstream ion channels may be a potential therapeutic strategy for PD motor dysfunction.
Animals ; Histamine/metabolism* ; Male ; Oxidopamine/toxicity* ; Rats ; Ventral Thalamic Nuclei/physiopathology* ; Rats, Sprague-Dawley ; Disease Models, Animal ; Parkinson Disease/metabolism* ; Neurons/physiology* ; Humans ; Optogenetics

A recombinant adenovirus(rAd)for expression of Mycobacterium tuberculosis(M.tb)c-di-AMP phosphodiesterase CnpB was constructed,and its induced humoral immune response was detected.The codon-optimized gene of M.tb CnpB was cloned into the adenoviral plasmid pcADV.The recombinant plasmid pcADV-CnpB was transfected into HEK293T cells,and expression was detected with Western blot.The recombinant plasmid pcADV-CnpB and the backbone plasmid were co-transfected into HEK293T cells to obtain the recombinant adenovirus rAd-CnpB.rAd-CnpB was amplified in HEK293T cells,and the target protein expression of rAd-CnpB was detected with Western blot and immunofluorescence.Mice were immunized with rAd-CnpB intranasally,and their sera and bronchoalveolar lavage fluid(BALF)were collected.ELISA was used to detect levels of antigen-specific antibodies.Restriction enzyme digestion and sequencing indicated that the recombinant plasmid pcADV-CnpB was successfully constructed and led to protein expression in eukaryotic cells.rAd-CnpB was packaged and produced in HEK293T cells.After amplification and purification,rAd-CnpB with a titer of 5.53×1010 PFU/mL was obtained.rAd-CnpB led to CnpB expression in HEK293T cells.Intranasal immunization with rAd-CnpB increased levels of IgG and secretory IgA in BALF and led to high levels of IgG in sera.rAd-CnpB,the recombinant adenovirus for expression of c-di-AMP phosphodiesterase CnpB was successfully constructed,and was found to induce antigen-specific humoral and mucosal immune responses through mucosal immunization.Thus,rAd-CnpB may be used in further research on new TB vaccine strategies.

A portable molecularly imprinted(MIP)surface-enhanced Raman scattering(SERS)chip was fabricated via a green electrochemical approach for highly selective detection of bisphenol A(BPA).This MIP-AuNP/UIO-66/SPE sensor was fabricated through a single-step co-deposition process.The process involved electropolymerization onto a UIO-66 modified screen-printed electrode(SPE),by usingo-phenylenediamine(OPD)as functional monomer and BPA as template,and simultaneously electro-reduction generated gold nanoparticles(AuNPs),which served as the SERS-active substrate.Ultimately,this one-step method formed a three-dimensional porous architecture on the electrode surface.Under 785 nm laser excitation,the sensing chip exhibited a highly sensitive SERS response towards BPA.The intensity of its characteristic peak at 850 cm-1 showed a good linear relationship with logarithm of BPA concentration in the range of 1.0×10-10 to 1.0×10-6 mol/L,with a detection limit of 1.0×10-12 mol/L.More importantly,the fabricated chips maintained highly selective binding affinity for BPA in water samples even in the presence of structural analogs bisphenol F(BPF)and bisphenol S(BPS).When the chip was applied to detection of BPA in water samples from plastic bottle and paper cup,the recovery rates ranged from 94.0%to 103.0%with relative standard deviations(RSD)less than 4.7%.The developed chip offered a highly sensitive and selective solution for detection of trace BPA in complex water samples.

A recombinant adenovirus(rAd)for expression of Mycobacterium tuberculosis(M.tb)c-di-AMP phosphodiesterase CnpB was constructed,and its induced humoral immune response was detected.The codon-optimized gene of M.tb CnpB was cloned into the adenoviral plasmid pcADV.The recombinant plasmid pcADV-CnpB was transfected into HEK293T cells,and expression was detected with Western blot.The recombinant plasmid pcADV-CnpB and the backbone plasmid were co-transfected into HEK293T cells to obtain the recombinant adenovirus rAd-CnpB.rAd-CnpB was amplified in HEK293T cells,and the target protein expression of rAd-CnpB was detected with Western blot and immunofluorescence.Mice were immunized with rAd-CnpB intranasally,and their sera and bronchoalveolar lavage fluid(BALF)were collected.ELISA was used to detect levels of antigen-specific antibodies.Restriction enzyme digestion and sequencing indicated that the recombinant plasmid pcADV-CnpB was successfully constructed and led to protein expression in eukaryotic cells.rAd-CnpB was packaged and produced in HEK293T cells.After amplification and purification,rAd-CnpB with a titer of 5.53×1010 PFU/mL was obtained.rAd-CnpB led to CnpB expression in HEK293T cells.Intranasal immunization with rAd-CnpB increased levels of IgG and secretory IgA in BALF and led to high levels of IgG in sera.rAd-CnpB,the recombinant adenovirus for expression of c-di-AMP phosphodiesterase CnpB was successfully constructed,and was found to induce antigen-specific humoral and mucosal immune responses through mucosal immunization.Thus,rAd-CnpB may be used in further research on new TB vaccine strategies.

BACKGROUND:Inflammation is one of the important factors that induce cerebral ischemia-reperfusion injury.Studies have shown that electroacupuncture can effectively reduce inflammation after ischemic stroke and improve the symptoms of neurological deficits,but the mechanism is not clear. OBJECTIVE:To observe the effect of electroacupuncture on Toll-like receptor 4/nuclear factor-κB in rats with cerebral ischemia-reperfusion injury. METHODS:Forty-eight male Sprague-Dawley rats were randomly divided into sham operation group,model group and electroacupuncture group,with 16 rats in each group.The rat model of cerebral ischemia-reperfusion injury was prepared by middle cerebral artery occlusion.At 24 hours after modeling,the rats in the electroacupuncture group were treated with electroacupuncture,once a day,20 minutes each time,for a total of 5 days.The sham operation group and the model group did not do any intervention.After 5 days of intervention,Longa method was used to evaluate the degree of neurological injury in rats.Triphenyl tetrazolium chloride staining and hematoxylin-eosin staining were used to measure the volume of cerebral infarction and the pathological changes of brain tissue in rats.Serum interleukin-6,interleukin-18 and tumor necrosis factor-α were detected by ELISA.Expressions of Toll-like receptor 4 and nuclear factor-κB in the cerebral cortex at mRNA and protein levels were detected by fluorescence quantitative PCR and western blot,respectively. RESULTS AND CONCLUSION:Compared with the sham operation group,the neurological function scores,serum interleukin-6,interleukin-18,and tumor necrosis factor-α levels,Toll-like receptor 4 and nuclear factor-κB mRNA and protein expression levels were significantly higher in the model group(P＜0.01).Compared with the model group,electroacupuncture significantly reduced the neurological function scores,serum interleukin-6,interleukin-18,and tumor necrosis factor-α levels,Toll-like receptor 4 and nuclear factor-κB mRNA and protein expression levels(P＜0.05,P＜0.01).Compared with the sham operation group,the volume of cerebral infarction in the model group increased significantly(P＜0.01).Compared with the model group,the volume of cerebral infarction in the electroacupuncture group decreased(P＜0.05).In the model group,the arrangement of neurons was disordered,some nerve cells disappeared,nuclei presented with pyknosis and incomplete structure.After electroacupuncture intervention,the degree of neuronal degeneration and neuronal loss in the cerebral cortex of rats were reduced compared with those in the model group.To conclude,electroacupuncture can significantly improve the neurobehavior of rats with cerebral ischemia-reperfusion injury,reduce brain tissue injury,and effectively reduce the level of serum inflammatory factors.The mechanism may be related to the inhibition of Toll-like receptor 4/nuclear factor-κB signaling pathway.

Aim To investigate the mechanisms of Chaijin JieYu Anshen formula modulating the depres-sive behaviors and the synaptic plasticity of hippocam-pal neurons in insomnia-concomitant depression rats based on the histone deacetylase 5(HDAC5)/myocyte enhancer factor 2C(MEF2C)pathway.Methods A rat model of insomnia-concomitant depression was es-tablished by PCPA injection combined with chronic un-predictable mild stress(CUMS),and the experiment was divided into the control group,the model group,the high,medium and low dose group of Chaijin JieYu Anshen formula,and the positive drug group.The de-pression of rats was evaluated by sugar-water prefer-ence test,open field test and morris water maze.The levels of 5-hydroxytryptamine(5-HT)and dopamine(DA)in serum were measured by enzyme linked im-munosorbent assay(ELISA).The pathological damage of hippocampal neurons was observed by HE staining and Nissl staining.The damage of dendritic spines of hippocampal neurons was observed by Golgi staining,and the levels of HDAC5,MEF2C,postsynaptic densi-ty-95(PSD-95)and synaptophysin 1(SYN1)in hip-pocampus were measured by Western blot,immunohis-tochemistry and immunofluorescence.Results Com-pared with the model group,the Chaijin JieYu Anshen formula could increase the sugar-water preference rate of the model rats,reduce the immobility time in the open field experiment,increase the total activity dis-tance,shorten the evasion latency in the localization navigation experiment,and prolong the residence time in the quadrant where the platform was located in the space exploration experiment(P＜0.05,P＜0.01).Moreover,the Chaijin JieYu Anshen formula improved the hippocampal neuron and dendritic spine damage and increase the dendritic branch length and dendritic spine density of hippocampal neurons(P＜0.01,P＜0.01),restore the serum levels of 5-HT and DA in insomnia-concomitant depression rats(P＜0.05,P＜0.01),down-regulate the HDAC5 protein,and up-regulate the expression of MEF2C,PSD-95,and SYN1 protein(P＜0.05,P＜0.01 or P＜0.001).Conclusions Chaijin JieYu Anshen formula may alle-viate the depression-like behavior of model rats by re-ducing the expression of HDAC5 protein,thus deregu-lating the inhibition of transcription factor MEF2C,promoting the expression of PSD-95 and SNY1 protein,and exerting a protective effect on hippocampal neurons and synapses.

Objective: To understand the current status of diagnosis and treatment of chronic lymphocytic leukemia (CLL) /small lymphocytic lymphoma (SLL) among hematologists, oncologists, and lymphoma physicians from hospitals of different levels in China. Methods: This multicenter questionnaire survey was conducted from March 2021 to July 2021 and included 1,000 eligible physicians. A combination of face-to-face interviews and online questionnaire surveys was used. A standardized questionnaire regarding the composition of patients treated for CLL/SLL, disease diagnosis and prognosis evaluation, concomitant diseases, organ function evaluation, treatment selection, and Bruton tyrosine kinase (BTK) inhibitor was used. Results: ①The interviewed physicians stated that the proportion of male patients treated for CLL/SLL is higher than that of females, and the age is mainly concentrated in 61-70 years old. ②Most of the interviewed physicians conducted tests, such as bone marrow biopsies and immunohistochemistry, for patient diagnosis, in addition to the blood test. ③Only 13.7% of the interviewed physicians fully grasped the initial treatment indications recommended by the existing guidelines. ④In terms of cognition of high-risk prognostic factors, physicians' knowledge of unmutated immunoglobulin heavy-chain variable and 11q- is far inferior to that of TP53 mutation and complex karyotype, which are two high-risk prognostic factors, and only 17.1% of the interviewed physicians fully mastered CLL International Prognostic Index scoring system. ⑤Among the first-line treatment strategy, BTK inhibitors are used for different types of patients, and physicians have formed a certain understanding that BTK inhibitors should be preferentially used in patients with high-risk factors and elderly patients, but the actual use of BTK inhibitors in different types of patients is not high (31.6%-46.0%). ⑥BTK inhibitors at a reduced dose in actual clinical treatment were used by 69.0% of the physicians, and 66.8% of the physicians had interrupted the BTK inhibitor for >12 days in actual clinical treatment. The use of BTK inhibitors is reduced or interrupted mainly because of adverse reactions, such as atrial fibrillation, severe bone marrow suppression, hemorrhage, and pulmonary infection, as well as patients' payment capacity and effective disease progression control. ⑦Some differences were found in the perceptions and behaviors of hematologists and oncologists regarding the prognostic assessment of CLL/SLL, the choice of treatment options, the clinical use of BTK inhibitors, etc. Conclusion: At present, a gap remains between the diagnosis and treatment of CLL/SLL among Chinese physicians compared with the recommendations in the guidelines regarding the diagnostic criteria, treatment indications, prognosis assessment, accompanying disease assessment, treatment strategy selection, and rational BTK inhibitor use, especially the proportion of dose reduction or BTK inhibitor discontinuation due to high adverse events.
Female ; Humans ; Male ; Aged ; Middle Aged ; Leukemia, Lymphocytic, Chronic, B-Cell/drug therapy* ; Prognosis ; Lymphoma, B-Cell ; Immunohistochemistry ; Immunoglobulin Heavy Chains/therapeutic use*

Objective: To analyze the clinicopathological characteristics of 11 cases of chronic lymphocytic leukemia (CLL) with t (14;19) (q32;q13) . Methods: The case data of 11 patients with CLL with t (14;19) (q32;q13) in the chromosome karyotype analysis results of the Blood Diseases Hospital, Chinese Academy of Medical Sciences from January 1, 2018, to July 30, 2022, were retrospectively analyzed. Results: In all 11 patients, t (14;19) (q32;q13) involved IGH::BCL3 gene rearrangement, and most of them were accompanied by +12 or complex karyotype. An immunophenotypic score of 4-5 was found in 7 patients and 3 in 4 cases. We demonstrated that CLLs with t (14;19) (q32;q13) had a mutational pattern with recurrent mutations in NOTCH1 (3/7), FBXW7 (3/7), and KMT2D (2/7). The very-high-risk, high-risk, intermediate-risk, and low-risk groups consisted of 1, 1, 6, and 3 cases, respectively. Two patients died, 8 survived, and 2 were lost in follow-up. Four patients had disease progression or relapse during treatment. The median time to the first therapy was 1 month. Conclusion: t (14;19) (q32;q13), involving IGH::BCL3 gene rearrangement, is a rare recurrent cytogenetic abnormality in CLL, which is associated with a poor prognosis.
Humans ; Leukemia, Lymphocytic, Chronic, B-Cell/genetics* ; Retrospective Studies ; Translocation, Genetic ; Chromosome Aberrations ; Karyotyping