Neurochemical imbalance is a contributing factor to neurological symptoms in multiple sclerosis (MS). The matured myelin sheath is crucial for substance transportation within the extracellular space (ECS) and for maintaining local homeostasis. Therefore, we hypothesize that disturbed ECS transportation following demyelinating lesions might lead to neurochemical imbalance in MS. In the current study, a lysophosphatidylcholine-induced unilateral MS model was used to investigate spatial neurochemical alterations. The results demonstrated that 168 substances were altered around the demyelination site in the ipsilateral hemisphere, compared to the contralateral hemisphere, with significant enrichment in the purine and arginine-proline metabolic pathways. Notably, dopamine was unexpectedly detected in the demyelinated region and the adjacent thalamus. Tracer-based MRI further revealed that the tracer injected into the striatum abnormally refluxed to the thalamus, with the area of reflux consistent with the altered dopamine distribution. The interstitial fluid drained extensively but was confined to the unilateral hemisphere, which may explain the observed widespread changes in other neuroactive substances. Importantly, after the restoration of ECS integrity, both interstitial fluid drainage and neurochemical imbalance, including dopamine, were normalized, supporting the potential link between ECS dysfunction and neurochemical imbalance. These observations highlight the crucial role of ECS transport in maintaining neurochemical homeostasis in the brain, providing new insights into the mechanisms that may underline the neuropsychiatric symptoms of MS.

Objective To investigate the influence of histone deacetylase 3 (HDAC3) on the occurrence, development of psoriasis-like inflammation in mice, and the relative immune mechanisms. Methods Healthy C57BL/6 mice aged 6-8 weeks were selected and randomly divided into 3 groups: control group (Control), psoriasis model group (IMQ), and HDAC3 inhibitor RGFP966-treated psoriasis model group (IMQ+RGFP966). One day prior to the experiment, the back hair of the mice was shaved. After a one-day stabilization period, the mice in Control group was treated with an equal amount of vaseline, while the mice in IMQ group was treated with imiquimod (62.5 mg/d) applied topically on the back to establish a psoriasis-like inflammation model. The mice in IMQ+RGFP966 group received intervention with a high dose of the HDAC3-selective inhibitor RGFP966 (30 mg/kg) based on the psoriasis-like model. All groups were treated continuously for 5 d, during which psoriasis-like inflammation symptoms (scaling, erythema, skin thickness), body weight, and mental status were observed and recorded, with photographs taken for documentation. After euthanasia, hematoxylin-eosin (HE) staining was used to assess the effect of RGFP966 on the skin tissue structure of the mice, and skin thickness was measured. The mRNA and protein expression levels of HDAC3 in skin tissues were detected using reverse transcription real-time quantitative polymerase chain reaction (RT-qPCR) and Western blot (WB), respectively. Flow cytometry was employed to analyze neutrophils in peripheral blood and lymph nodes, CD4+ T lymphocytes, CD8+ T lymphocytes in peripheral blood, and IL-17A secretion by peripheral blood CD4+ T lymphocytes. Additionally, spleen CD4+ T lymphocyte expression of HDAC3, CCR6, CCR8, and IL-17A secretion levels were analyzed. Immunohistochemistry was used to detect the localization and expression levels of HDAC3, IL-17A, and IL-10 in skin tissues. Results Compared with the Control group, the IMQ group exhibited significant psoriasis-like inflammation, characterized by erythema, scaling, and skin wrinkling. Compared with the IMQ group, RGFP966 exacerbated psoriasis-like inflammatory symptoms, leading to increased hyperkeratosis. The psoriasis area and severity index (PASI) skin symptom scores were higher in the IMQ group than those in the Control group, and the scores were further elevated in the IMQ+RGFP966 group compared to the IMQ group. Skin thickness measurements showed a trend of IMQ+RGFP966>IMQ>Control. The numbers of neutrophils in the blood and lymph nodes increased sequentially in the Control, IMQ, and IMQ+RGFP966 groups, with a similar trend observed for CD4+ and CD8+ T lymphocytes in the blood. In skin tissues, compared with the Control group, the mRNA and protein levels of HDAC3 decreased in the IMQ group, but RGFP966 did not further reduce these expressions. HDAC3 was primarily located in the nucleus. Compared with the Control group, the nuclear HDAC3 content decreased in the skin tissues of the IMQ group, and RGFP966 further reduced nuclear HDAC3. Compared with the Control and IMQ groups, RGFP966 treatment decreased HDAC3 expression in splenic CD4+ and CD8+ T cells. RGFP966 treatment increased the expression of CCR6 and CCR8 in splenic CD4+ T cells and enhanced IL-17A secretion by peripheral blood and splenic CD4+ T lymphocytes. Additionally, compared with the IMQ group, RGFP966 reduced IL-10 protein levels and upregulated IL-17A expression in skin tissues. Conclusion RGFP966 exacerbates psoriatic-like inflammatory responses by inhibiting HDAC3, increasing the secretion of the cytokine IL-17A, and upregulating the expression of chemokines CCR8 and CCR6.

Lung cancer is the second most common cancer in the world. Myeloid-derived suppressor cells (MDSCs) are important cell populations in the microenvironment of lung cancer, which affects the development and treatment of lung cancer. A large number of studies have shown that miRNA can regulate MDSCs, promoting tumor development. Here we aim to explore the role of miR- 150 on MDSCs in lung tumors. We established lung tumor models by injecting miR- 150 knock-out (miR- 150 KO) mice with LLC subcutaneously. MiR- 150 deletion promoted tumor growth and increased the ratio of MDSCs in tumors. In addition, knockdown of miR- 150 resulted in high serum levels of IL- 6 and G-CSF and promoted the expression of suppressive-associated molecules in MDSCs. In vitro, inhibition of miR- 150 led to increased expression of ROS, IRE1α and P-STAT3 in MDSCs. In vivo administration of STAT3 inhibitor significantly inhibited tumor growth in miR- 150 KO mice and reduced ROS level in tumor MDSCs. Our results indicated that miR- 150 deletion promotes lung tumor growth by upregulating P-STAT3 and ROS in MDSCs, suggesting that STAT3 inhibitors are effective in blocking the production of ROS in MDSCs lacking miR- 150.

HDAC3 has been demonstrated to play a crucial role in the progression of various tumors and the differentiation and development of T cells. However, its impact on peripheral T cells in the development of murine lung cancer remains unclear. In this experiment, a subcutaneous lung tumor model was established in C57BL/6 mice, and tumor-bearing mice were treated with the specific inhibitor of HDAC3, RGFP966, at different doses to observe changes in tumor size. Additionally, a lung tumor model was established using hdac3fl/fl cd4cre+/+ mice to investigate its mechanism. Mice injected with 10mg/kg RGFP966 had the smallest tumor volume, while those injected with 30mg/kg RGFP966 had the largest tumors. Flow cytometry analysis revealed that the expression of HDAC3 in splenic T cells was reduced in all groups of mice, while IFN-γ and IL-17A were increased. Moreover, the expression of granzyme B and perforin in splenic CD8+ T cells was increased in all groups of mice. Compared to the use of 30mg/kg RGFP966 alone, the combination with anti-IL-17A mAb reduced the infiltration of Neutrophils and exhausted T cells in mouse tumors, thereby impeding tumor development. These findings demonstrate that the use of RGFP966 or T cell-specific loss of hdac3 promotes the expression of IL-17A in splenic T cells, leading to tumor resistance and providing insights for clinical treatment.

Vγ9Vδ2 T cells are specialized effector cells that have gained prominence as immunotherapy agents due to their ability to target and kill cells with altered pyrophosphate metabolites. In our effort to understand how cancer cells evade the cell-killing activity of Vγ9Vδ2 T cells, we performed a comprehensive genome-scale CRISPR screening of cancer cells. We found that four molecules belonging to the butyrophilin (BTN) family, specifically BTN2A1, BTN3A1, BTN3A2, and BTN3A3, are critically important and play unique, nonoverlapping roles in facilitating the destruction of cancer cells by primary Vγ9Vδ2 T cells. The coordinated function of these BTN molecules was driven by synchronized gene expression, which was regulated by IFN-γ signaling and the RFX complex. Additionally, an enzyme called QPCTL was shown to play a key role in modifying the N-terminal glutamine of these BTN proteins and was found to be a crucial factor in Vγ9Vδ2 T cell killing of cancer cells. Through our research, we offer a detailed overview of the functional genomic mechanisms that underlie how cancer cells escape Vγ9Vδ2 T cells. Moreover, our findings shed light on the importance of the harmonized expression and function of gene family members in modulating T-cell activity.

Time-stamped cross-sectional data, which lack linkage across time points, are commonly generated in single-cell transcriptional profiling. Many previous methods for inferring gene regulatory networks (GRNs) driving cell-state transitions relied on constructing single-cell temporal ordering. Introducing COSLIR (COvariance restricted Sparse LInear Regression), we presented a direct approach to reconstructing GRNs that govern cell-state transitions, utilizing only the first and second moments of samples between two consecutive time points. Simulations validated COSLIR's perfect accuracy in the oracle case and demonstrated its robust performance in real-world scenarios. When applied to single-cell RT-PCR and RNAseq datasets in developmental biology, COSLIR competed favorably with existing methods. Notably, its running time remained nearly independent of the number of cells. Therefore, COSLIR emerges as a promising addition to GRN reconstruction methods under cell-state transitions, bypassing the single-cell temporal ordering to enhance accuracy and efficiency in single-cell transcriptional profiling.

Objective To investigate the role of histone deacetylase 3 (HDAC3) in the differentiation and function of peripheral CD4(+) T cells. Methods CD4cre enzyme mediated HDAC3 heterozygous gene deletion mice (Hdac3(fl/fl)CD4(cre+/-)) and wild-type normal control (Hdac3(fl/fl), WT) mice were used. The effects of HDAC3 deletion on the proportion and number of peripheral CD4(+) and CD8(+) T cells were detected by flow cytometry. The effects of HDAC3 deletion on the expression of IFN-gamma, IL-4 and IL-17A in CD4(+) T cells and Tfh cells were detected under the in vitro PMA and Ionomycin stimulation. The effects of HDAC3 deletion on the expression of IFN-gamma, IL-4 and IL-17 in serum were detected by ELISA. The naive CD4(+) T cells of Hdac3(fl/fl)CD4(cre+/-) and WT mice were sorted and cultured in Th1 and Th2 differentiation conditions respectively. The effects of HDAC3 deletion on the expression of Th1, Th2 and Th17 related cytokines and their specific transcription factors were detected by intracellular staining. The effects of HDAC3 deletion on the expression of genes related to CD4(+) T cell differentiation subsets were detected by gene expression microarray. The mice treated with streptozotocin (STZ) were used to construct type 1 diabetes mellitus (T1DM) disease model, and the effects of HDAC3 deletion on the pathogenesis of T1DM were detected. Results Compared with WT mice, the proportion and number of peripheral CD4(+) and CD8(+) T cells in Hdac3(fl/fl)CD4(cre+/-) mice decreased significantly. The expression of IFN-gamma in CD4(+) T cells and serum of Hdac3(fl/fl)CD4c(re+/-) mice decreased significantly, while the expression of IL-4 and IL-17A increased significantly, and the proportion of Tfh cells also increased significantly. HDAC3 deletion inhibited the differentiation of CD4(+) T cells into Th1 cells, but promoted their differentiation intoTh2 cells. Microarray analysis showed that the deletion of HDAC3 resulted in the decrease of gene expression in Th1 cell lineage, while the increase of gene expression in Th2, Th17 and Tfh cell lineage. Under the condition of STZ induction, HDAC3 deletion inhibited the development of T1DM and the differentiation of CD4(+) T cells into Th1. Conclusion HDAC3 promotes the differentiation of peripheral CD4(+) T cells into Th1 cells and aggravates the occurrence of T1DM.