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Background: Loss-of-function mutations of ZBTB24 cause immunodeficiency, centromeric instability, and facial anomalies syndrome 2 (ICF2). ICF2 is a rare autosomal recessive disorder with immunological defects in serum antibodies and circulating memory B cells, resulting in recurrent and sometimes fatal respiratory and gastrointestinal infections. The genotype–phenotype correlation in patients with ICF2 indicates an essential role of ZBTB24 in the terminal differentiation of B cells. Methods: We used the clustered regularly interspaced short palindromic repeats (CRISPER)/Cas9 technology to generate B cell specific Zbtb24-deficient mice and verified the deletion specificity and efficiency by quantitative polymerase chain reaction (Q-PCR) and western blotting analyses in fluorescence-activated cell sorting (FACS)-sorted cells. The development, phenotype of B cells and in vivo responses to T cell dependent or independent antigens post immunization were analyzed by flow cytometry and enzyme-linked immunosorbent assay (ELISA). Adoptive transfer experiment in combination with in vitro cultures of FACS-purified B cells and RNA-Seq analysis were utilized to specifically determine the impact of Zbtb24 on B cell biology as well as the underlying mechanisms. Results: Zbtb24 is dispensable for B cell development and maintenance in naive mice. Surprisingly, B cell specific deletion of Zbtb24 does not evidently compromise germinal center reactions and the resulting primary and secondary antibody responses induced by T cell dependent antigens (TD-Ags), but significantly inhibits T cell independent antigen-elicited antibody productions in vivo. At the cellular level, Zbtb24-deficiency specifically impedes the plasma cell differentiation of B1 cells without impairing their survival, activation and proliferation in vitro. Mechanistically, Zbtb24-ablation attenuates heme biosynthesis partially through mTORC1 in B1 cells, and addition of exogenous hemin abrogates the differentiation defects of Zbtb24-null B1 cells. Conclusions: Zbtb24 seems to regulate antibody responses against TD-Ags B cell extrinsically, but it specifically promotes the plasma cell differentiation of B1 cells via heme synthesis in mice. Our study also suggests that defected B1 functions contribute to recurrent infections in patients with ICF2. [ABSTRACT FROM AUTHOR]

Background: Ischemic heart disease (IHD) has a high mortality in the population. Although serum creatinine (Cr) and serum total bilirubin (TBil) are rapid and readily available biomarkers in routine blood tests, there is a lack of literature on the prognostic value of combined Cr and TBil tests for IHD. This study aimed to evaluate a combined equation based on Cr and TBil to predict the long-term risk of death in IHD and to find indicators sensitive to the prognosis of IHD patients. Method: In this study, 2625 patients with IHD were included, and the combined value and combined equations of Cr and TBil were obtained by logistic regression analysis based on Cr and TBil collected at the time of admission. Patients were divided into four groups according to the quartiles of the combined value. COX proportional hazard regression model was used to analyze the risk factors for long-term death in IHD patients. Receiver operating characteristic (ROC) curves were used to evaluate the prognostic effect of Cr, TBil and combined value on long-term death events. Results: Logistic regression analysis was performed for long-term death events with Cr and TBil as independent variables, and the logit regression model was Logit(P) = 0.0129×TBil+0.007×Cr-0.417. Multifactorial Cox regression analysis showed that high values of the equation were independent risk factors for long-term death events (all-cause death: HR 1.457, 95% CI 1.256–1.689, P<0.001; cardiovascular death: HR 1.452, 95% CI 1.244–1.695, P<0.001). Combined Cr and TBil value are more valuable in predicting long-term death (AUC: 0.609, 95% CI 0.587–0.630, P<0.001). Conclusion: Combined Cr and TBil assay is superior to single biomarkers for predicting long-term death in patients with IHD. High values of the equation are independent predictors of long-term death and can be used to identify patients at high risk for IHD. [ABSTRACT FROM AUTHOR]

An endoplasmic reticulum resident protein, calreticulin (CRT), participates in many cellular processes. CRT is a tumor-associated antigen with an important role in antitumor immunity. Previously, we reported that the recombinant CRT fragment 39-272 (CRT/39-272) exhibited superior immunobiological activity, activating macrophages to release cytokines and promoting dendritic cell (DC) maturation. However, the effect of CRT/39-272 in vivo, especially its adjuvant effect on in vivo antitumor immune responses, was not fully investigated. In this study, we constructed a fusion protein linking CRT/39-272 to an ovalbumin (OVA) peptide (residues 182-297, OVAp) and used the fusion protein (OVAp-CRT) to examine the adjuvant effect of CRT. We investigated whether CRT/39-272 could induce bone marrow-derived DC maturation and strongly promote the proliferation of OVA-specific T cells in vitro. Compared with OVAp, OVAp-CRT induced stronger antigen-specific T lymphocyte responses, including antigen-specific T cell proliferation, interferon-γ secretion, and cytotoxic T lymphocyte responses. OVAp-CRT-immunized mice generated significantly increased OVAp-specific antibody and CD4+/CD8+ memory T cells, which mediated long-term protective effects. OVAp-CRT upregulated CD40, CD80, and CD86 expressions in splenic conventional DCs. Furthermore, OVAp-CRT protected immunized mice against OVA-expressing B16 melanoma cells in vivo. Moreover, mice that were adoptively transferred with OVAp-CRT-pulsed DCs showed inhibited tumor growth and prolonged mouse survival. Our results demonstrate that CRT/39-272 can be used as a potential new adjuvant for tumor vaccines, and this finding may be useful in tumor vaccine development. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA) is a chronic autoimmune disease accompanied by local and systemic bone loss. FcγRs, especially FcγRIIa (hFcγRIIa), have been implicated in the pathogenesis of RA. However, the contribution of hFcγRIIa to bone loss has not been fully elucidated. In the present study, we demonstrated the double-edged sword role of hFcγRIIa on osteoclast differentiation through investigations involving hFcγRIIa-transgenic (hFcγRIIa-Tg) mice. Our findings reveal that hFcγRIIa-Tg mice, previously shown to exhibit heightened susceptibility to collagen-induced arthritis (CIA), displayed increased osteoporosis during CIA or at advanced ages (40 weeks), accompanied by heightened in vivo osteoclast differentiation. Notably, bone marrow cells from hFcγRIIa-Tg mice exhibited enhanced efficiency in differentiating into osteoclasts and bone resorption in vitro compared to wild-type mice when stimulated with receptor activators of NF-κB ligand (RANKL). Additionally, hFcγRIIa-Tg mice exhibited augmented sensitivity to RANKL-induced bone loss in vivo , highlighting the osteoclast-promoting role of hFcγRIIa. Mechanistically, bone marrow cells from hFcγRIIa-Tg mice displayed heightened Syk self-activation, leading to mTOR-pS6 pathway activation, thereby promoting RANKL-driven osteoclast differentiation. Intriguingly, while hFcγRIIa crosslinking hindered RANKL-induced osteoclast differentiation, it activated the kinase cAbl, subsequently triggering STAT5 activation and inhibiting the expression of osteoclast-associated genes. This study provides novel insights into hFcγRIIa-mediated osteoclast biology, suggesting promising therapeutic targets for managing bone remodeling disorders., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Miao, Wang, Pan, Gong, Gao and Gong.)

Objectives: To investigate the effect of "Tongdu Qishen" acupuncture［dredging the Govern Vessel and normalizing mental activities, electroacupuncture (EA) of "Baihui" (GV20), "Yintang" (EX-HN3) and "Shuigou" (GV26) needling］on the learning-memory ability and the mechanism of ferroptosis in Alzheimer's disease (AD) mice., Methods: Twenty-four male APPswe/PS1dE9 mice were randomly and equally divided into model group and EA group, and 12 normal C57BL/6 mice were used as the control group. In the EA group, EA (2 Hz/100 Hz, 20 min) was applied to GV20 and EX-HN3 in combination with manual acupuncture stimulation of GV26. The treatment was performed once a day, for a total of 28 days. The mice in the three groups were given the same fixation and grasping operation. Morris water maze swimming tests were used to assess the mice's learning-memory ability. Nissl staining and transmission electron microscopy were used to observe the morphological changes of neurons in the hippocampus. The activity of superoxide dismutase (SOD) in the hippocampus tissue was detected by superoxide anionic colorimetric assay kit (WST-1), and malondialdehyde (MDA) contents were detected by thiobarbituric acid (TBA) method. The expression levels of prostaglandin endoperoxide synthase 2 (ptgs2) and glutathione peroxidase 4 (GPX4) mRNA in the hippocampus were detected by fluorescent quantitative real-time PCR., Results: Behavioral results showed that compared with the control group, the escape latencies at the 2 nd , 3 rd , 4 th and 5 th day of Morris water maze swimming test were significantly increased ( P <0.05), and the swimming time in the original platform quadrant and the times of cros-sing the original platform were considerably decreased ( P <0.05) in the model group. In comparison with the model group, the escape latencies at the 4 th and 5 th day were strikingly decreased ( P <0.05), and the swimming time in the original platform quadrant and times of crossing the original platform significantly increased ( P <0.05) in the EA group. Following modeling, the SOD activity and the expression of GPX4 mRNA were obviously down-regulated ( P <0.05), and the content of MDA and the expression of ptgs2 mRNA significantly up-regulated ( P <0.05) in the model group rele-vant to the control group. The SOD activity and the expression of GPX4 mRNA were apparently increased ( P <0.05), and the content of MDA and the expression of ptgs2 mRNA remarkably down-regulated ( P <0.05) in the EA group rele-vant to the model group. Histopathological and ultrastructural results showed scattered arrangement of cells, widened space among cells, reduction in the number of cells, and many shrunk of dissolved nucleoli, shrunking and incomplete mitochondria, and high membrane electron density in the hippocampus of the model group, which was relatively milder in the EA group., Conclusions: "Tongdu Qishen" acupuncture can improve the learning-memory ability of AD mice, which may be related to its functions in up-regulating SOD activity and GPX4 mRNA expression, and down-regulating MDA content and ptgs2 mRNA expression to reduce the lipid peroxidation in the process of ferroptosis.

Objective: To observe the effect of electroacupuncture(EA) on activities of A2 type astrocytes(A2s)and A1 type astrocytes (A1s) , expressions of neurofilament protein 200 (NF-200, a marker of axon regeneration), nexin 1(NL1, a marker of synaptic regeneration), and regeneration of Nissl bodies in rats with spinal cord injury (SCI), so as to explore its mechanisms underlying improvement of SCI., Methods: A total of 75 male SD rats were rando-mized into sham operation, model, antibody neutralizing (AN), EA and EA+AN groups, with 15 rats in each group. The SCI model was established by using an infinite field impactor to deliver an about 200 k dyne weight onto the exposed spinal cord after making a dorsal laminectomy at vertebral level T10. EA (2 Hz, 1 mA) was applied to"Dazhui"(GV14) and "Mingmen"(GV4) for 20 min, once daily for 28 days. After modeling, intraspinal injection of neutralizing antibodies IL-1α, TNF-α and complement 1q (C1q, 2 μL) to the injured spinal locus for inhibition of A1 type astrocytes (A1s) was conducted on the 1 st , 7 th , 14 th and 21 st day for rats of AN and EA+AN groups. BBB rating scale was used to evaluate hindlimb locomotor function on day 1, 7, 14, 21 and 28 after modeling. The activation of A2s (its specific marker S100a10), astrocyte (its specific marker glial fibrillary acidic protein, GFAP), and A1s (its specific marker C3) in the spinal cord was detected by immunofluorescence, and the protein expressions of NF-200 and NL1 in the spinal cord detected by Western blot and immunohistochemistry, separately, and the neuronal regeneration was observed after Nissl staining., Results: After SCI, the BBB scores at 1 , 7, 14, 21 and 28 day, and the immunoactivity of NL1 and NF-200 were significantly decreased ( P <0.01), and the fluorescence intensity of double labelled S100a10 (A2s)/GFAP and C3, and the expression of NF-200 were considerably increased in the model group ( P <0.05, P <0.01). In contrast to the model group, the BBB scores at 7, 14, 21 and 28 day, and the immunoactivity of NL1 and NF-200, and the fluorescence intensity of A2s/GFAP in the AN, EA and AN+EA groups, and the expressions of NL1 in the EA and AN+EA groups, and expression of NF-200 protein in the AN+EA group were evidently increased ( P <0.05, P <0.01), and the fluorescence intensity of C3 was strikingly decreased in the EA group ( P <0.01). The effect of AN+EA was significantly superior to that of single AN and EA in increasing BBB scores at 14, 21 and 28 day, and in up-regulating the immunoactivity of NF-200( P <0.01, P <0.05). Nissl staining showed damaged structure of the gray matter of the spinal cord, atrophy of the Nissl body, and pyknosis of neurons, which was milder in the AN and EA groups, particularly in the AN+EA group., Conclusion: EA at GV14 and GV4 may promote activation of A2s and promote regeneration of axons and synapses in SCI model rats.