Subregions of the fusiform gyrus are differentially involved in the attentional mechanism supporting visual mental imagery in depression.

BACKGROUND: Impaired visual mental imagery is an important symptom of depression and has gradually become an intervention target for cognitive behavioral therapy. METHODS: Our study involved a total of 25 healthy controls (HC) and 23 individuals with moderate depressive symptoms (MD). This study explored the attentional mechanism supporting visual mental imagery impairments in depression using the Vividness of Visual Imagery Questionnaire (VVIQ), attentional network test (ANT), and resting-state functional magnetic resonance imaging (rs-fMRI). The intrinsic activity of attention-related regions relative to those supporting visual mental imagery was identified in depression patients. In addition, a meta-analysis was used to describe the cognitive function related to this intrinsic activity. RESULTS: The global correlation (GCOR) of the right anterior fusiform gyrus (FG) was decreased in depression patients. Attention-related areas were concentrated in the right posterior FG; the anterior and posterior functional connectivity (FC) of the FG was decreased in depression patients. Graph theoretic analysis showed that the degree of the right anterior FG was decreased, the degree of the anterior insula was increased, and the negative connection between these two regions was strengthened in depression patients. In addition, the degree of the right anterior FG, the FC between the subregions of the right FG, and the FC between the right anterior FG and insula were correlated with VVIQ scores; however, this correlation was not significant in depression patients. The meta-analysis suggested that the changes in the anterior FG in depressed patients may stem from difficulties of semantic memory retrieval. CONCLUSION: The changed intrinsic activity of subregions of the FG relative to the semantic memory retrieval may be associated with visual mental imagery impairments in depression.

Pirfenidone alleviates chronic pancreatitis via suppressing the activation of pancreatic stellate cells and the M1 polarization of macrophages.

In the realm of fibroinflammatory conditions, chronic pancreatitis (CP) stands out as a particularly challenging ailment, lacking a dedicated, approved treatment. The potential of Pirfenidone (PFD), a drug originally used for treating idiopathic pulmonary fibrosis (IPF), in addressing CP's fibrotic aspects has sparked new interest. This investigation focused on the role of PFD in diminishing fibrosis and immune response in CP, using a mouse model induced by caerulein. The research extended to in vitro studies examining the influence of PFD on pancreatic stellate cells' (PSCs) behavior and the polarization of macrophages into M1 and M2 types. Advanced techniques like RNA sequencing and comprehensive data analyses were employed to decode the molecular interactions of PFD with PSCs. Supplementary experiments using techniques such as quantitative real-time PCR, western blotting, and immunofluorescence were also implemented. Results showed a notable reduction in pancreatic damage in PFD-treated mice, manifested through decreased acinar cell atrophy, lower collagen deposition, and a reduction in macrophage presence. Further investigation revealed PFD's capacity to hinder PSCs' migration, growth, and activation, alongside a reduction in the production and secretion of extracellular matrix proteins. This effect is primarily achieved by interfering with signaling pathways such as TGF-ß/Smad, Wnt/ß-catenin, and JAK/STAT. Additionally, PFD selectively hampers M1 macrophage polarization through the STAT3 pathway, without impacting M2 polarization. These outcomes highlight PFD's dual mechanism in moderating PSC activity and M1 macrophage polarization, positioning it as a promising candidate for CP therapy.

NCAM mimetic peptide P2 synergizes with bone marrow mesenchymal stem cells in promoting functional recovery after stroke.

The neural cell adhesion molecule (NCAM) promotes neural development and regeneration. Whether NCAM mimetic peptides could synergize with bone marrow mesenchymal stem cells (BMSCs) in stroke treatment deserves investigation. We found that the NCAM mimetic peptide P2 promoted BMSC proliferation, migration, and neurotrophic factor expression, protected neurons from oxygen-glucose deprivation through ERK and PI3K/AKT activation and anti-apoptotic mechanisms in vitro. Following middle cerebral artery occlusion (MCAO) in rats, P2 alone or in combination with BMSCs inhibited neuronal apoptosis and induced the phosphorylation of ERK and AKT. P2 combined with BMSCs enhanced neurotrophic factor expression and BMSC proliferation in the ischemic boundary zone. Moreover, combined P2 and BMSC therapy induced translocation of nuclear factor erythroid 2-related factor, upregulated heme oxygenase-1 expression, reduced infarct volume, and increased functional recovery as compared to monotreatments. Treatment with LY294002 (PI3K inhibitor) and PD98059 (ERK inhibitor) decreased the neuroprotective effects of combined P2 and BMSC therapy in MCAO rats. Collectively, P2 is neuroprotective while P2 and BMSCs work synergistically to improve functional outcomes after ischemic stroke, which may be attributed to mechanisms involving enhanced BMSC proliferation and neurotrophic factor release, anti-apoptosis, and PI3K/AKT and ERK pathways activation.

Analysis of the influences of social isolation on cognition and the therapeutic potential of deep brain stimulation in a mouse model.

Background: Social interaction is a fundamental human need. Social isolation (SI) can have negative effects on both emotional and cognitive function. However, it is currently unclear how age and the duration of SI affect emotion and recognition function. In addition, there is no specific treatment for the effects of SI. Methods: The adolescence or adult mice were individually housed in cages for 1, 6 or 12 months and for 2 months to estabolish SI mouse model. We investigated the effects of SI on behavior in mice at different ages and under distinct durations of SI, and we explored the possible underlying mechanisms. Then we performed deep brain stimulation (DBS) to evaluate its influences on SI induced behavioral abnormalities. Results: We found that social recognition was affected in the short term, while social preference was damaged by extremely long periods of SI. In addition to affecting social memory, SI also affects emotion, short-term spatial ability and learning willingness in mice. Myelin was decreased significantly in the medial prefrontal cortex (mPFC) and dorsal hippocampus of socially isolated mice. Cellular activity in response to social stimulation in both areas was impaired by social isolation. By stimulating the mPFC using DBS, we found that DBS alleviated cellular activation disorders in the mPFC after long-term SI and improved social preference in mice. Conclusion: Our results suggest that the therapeutic potential of stimulating the mPFC with DBS in individuals with social preference deficits caused by long-term social isolation, as well as the effects of DBS on the cellular activity and density of OPCs.

Mesenchymal Stem Cell Therapy for Huntington Disease: A Meta-Analysis.

Objective: Mesenchymal stem cell (MSC) therapy has been explored in Huntington disease (HD) as a potential therapeutic approach; however, a complete synthesis of these results is lacking. We conducted a meta-analysis to evaluate the effects of MSCs on HD. Method: Eligible studies published before November 2022 were screened from Embase, PubMed, Web of Science, Medline, and Cochrane in accordance with PRISMA guidelines. ClinicalTrial.gov and the World Health Organization International Clinical Trials Registry Platform were also searched for registered clinical trials. The outcomes in rodent studies evaluated included morphological changes (striatal volume and ventricular volume), motor function (rotarod test, wire hang test, grip strength test, limb-clasping test, apomorphine-induced rotation test, and neuromuscular electromyography activity), cognition (Morris water maze test), and body weight. Result: The initial search returned 362 records, of which 15 studies incorporating 346 HD rodents were eligible for meta-analysis. Larger striatal and smaller ventricular volumes were observed in MSC-treated animals compared to controls. MSCs transplanted before the occurrence of motor dysfunction rescued the motor incoordination of HD. Among different MSC sources, bone marrow mesenchymal stem cells were the most investigated cells and were effective in improving motor coordination. MSC therapy improved muscle strength, neuromuscular electromyography activity, cortex-related motor function, and striatum-related motor function, while cognition was not changed. The body weight of male HD rodents increased after MSC transplantation, while that of females was not affected. Conclusion: Meta-analysis showed a positive effect of MSCs on HD rodents overall, as reflected in morphological changes, motor coordination, muscle strength, neuromuscular electromyography activity, cortex-related motor function, and striatum-related motor function, while cognition was not changed by MSC therapy.

[Effect of Shugan Tiaoshen acupuncture combined with western medication on depression-insomnia comorbidity due to COVID-19 quarantine: a multi-central randomized controlled trial].

OBJECTIVE: To observe the effect of Shugan Tiaoshen acupuncture (acupuncture for soothing the liver and regulating the mentality) combined with western medication on depression and sleep quality in the patients with depression-insomnia comorbidity due to COVID-19 quarantine, and investigate the potential mechanism from the perspective of cortical excitability. METHODS: Sixty patients with depression-insomnia comorbidity due to COVID-19 quarantine were randomly divided into an acupuncture group and a sham-acupuncture group, 30 cases in each one. The patients of both groups were treated with oral administration of sertraline hydrochloride tablets. In the acupuncture group, Shugan Tiaoshen acupuncture was supplemented. Body acupuncture was applied to Yintang (GV 24+), Baihui (GV 20), Hegu (LI 4), Zhaohai (KI 6), Qihai (CV 6), etc. The intradermal needling was used at Xin (CO15), Gan (CO12) and Shen (CO10). In the sham-acupuncture group, the sham-acupuncture was given at the same points as the acupuncture group. The compensatory treatment was provided at the end of follow-up for the patients in the sham-acupuncture group. In both groups, the treatment was given once every two days, 3 times a week, for consecutive 8 weeks. The self-rating depression scale (SDS) and insomnia severity index (ISI) scores were compared between the two groups before and after treatment and 1 month after the end of treatment (follow-up) separately. The cortical excitability indexes (resting motor threshold [rMT], motor evoked potential amplitude [MEP-A], cortical resting period [CSP]) and the level of serum 5-hydroxytryptamine (5-HT) were measured before and after treatment in the two groups. RESULTS: After treatment and in follow-up, SDS and ISI scores were decreased in both groups compared with those before treatment (P<0.05), and the scores in the acupuncture group were lower than those in the sham-acupuncture group (P<0.05), and the decrease range in the acupuncture group after treatment was larger than that in the sham-acupuncture group (P<0.05). After treatment, rMT was reduced (P<0.05), while MEP-A and CSP were increased (P<0.05) in the acupuncture group compared with that before treatment. The levels of serum 5-HT in both groups were increased compared with those before treatment (P<0.05). The rMT in the acupuncture group was lower than that in the sham-acupuncture group, while MEP-A and CSP, as well as the level of serum 5-HT were higher in the acupuncture group in comparison with the sham-acupuncture group (P<0.05). CONCLUSION: Shugan Tiaoshen acupuncture combined with western medication can relieve depression and improve sleep quality in the patients with depression-insomnia comorbidity due to COVID-19 quarantine, which is probably related to rectifying the imbalanced excitatory and inhibitory neuronal functions.

[Effects of electroacupuncture on the expression of serum exosomes and pro-inflammatory factors in spinal cord of rats with spinal cord injury].

OBJECTIVE: To investigate the effect of electroacupuncture (EA) on the morphology and microstructure of spinal cord tissue, the expression of serum exosomes, and the pro-inflammatory factors interleukin (IL)-1ß and IL-6 in spinal cord of rats with spinal cord injury (SCI), so as to explore the underlying mechanism of EA in the treatment of SCI. METHODS: Twenty-four female Wistar rats were randomly divided into sham operation group, model group, EA group, EA+GW4869 group, with 6 rats in each group. The SCI model was established by impinging spinal cord at T10 with a hammer, while the vertebral lamina was only opened without impingement for rats in sham operation group. Rats in EA group received EA intervention at "Jiaji"(EX-B7) acupoints at bilateral T9 and T10 (0.4-0.6 mA, 100 Hz), 3 h after modeling, once a day, for 7 concecutive days. Besides the treatment as EA group, rats in the EA+GW4869 group received injection of exosome inhibitor GW4869(200 µL, 300 µg/mL) once every 2 days from the day before modeling. Motor function of hind limbs of rats was evaluated using BBB scores. The histopathological changes of spinal cord were observed under light mircoscope after H.E. staining. Microstructure of spinal cord was observed and extracted serum exosomes were identified by using transmission electron microscopy. The expression of exosome marker proteins in serum exosomes, the levels of IL-1ß and IL-6 in spinal cord were detected by Western blot. RESULTS: H.E. stanining showed severe tissue looseness, inflammatory cell infiltration, cellular hydropic degeneration in spinal cord of the model group, which were relatively milder in the EA and EA+GW4869 groups. Under transmission electron microscopy, there were nerve fiber disintegration, myelin sheath structure dispersion, axonal atrophy with submembrane edema and widened space, and mitochondrial swelling in spinal cord of rats in the model group, with the lesions in EA group milder than EA+GW4869 group, which were both moderate. Typical exosomes were detected by transmission electron microscope in the extracted serum of rats in each group after ultracentrifugation. Compared with the sham operation group, the motor function scores was significantly decreased (P<0.01), the expression of IL-6 and IL-1ß in the spinal cord was significantly increased (P<0.01), while the expression of serum exosome marker protein CD81 was slightly increased in rats of the model group. Compared with the model group, the motor function scores was significantly increased (P<0.01), the expression of IL-6 and IL-1ß in the spinal cord was significantly decreased (P<0.01) in rats of the EA and EA+GW4869 group, while the expression of serum CD81 protein was slightly increased in rats of the EA group. Compared with the EA+GW4869 group, the expression of IL-6 and IL-1ß in the spinal cord was significantly decreased (P<0.01), while the expression of serum CD81 protein was slightly increased in rats of the EA group. However, there was no significance in expression of CD81 between each group mentioned above. CONCLUSION: EA can promote the secretion of serum exosomes and inhibit the expression of pro-inflammatory cytokines IL-6 and IL-1ß, so as to improve the microenvironment of injured spinal cord and SCI.

Transcranial low-intensity ultrasound stimulation for treating central nervous system disorders: A promising therapeutic application.

Transcranial ultrasound stimulation is a neurostimulation technique that has gradually attracted the attention of researchers, especially as a potential therapy for neurological disorders, because of its high spatial resolution, its good penetration depth, and its non-invasiveness. Ultrasound can be categorized as high-intensity and low-intensity based on the intensity of its acoustic wave. High-intensity ultrasound can be used for thermal ablation by taking advantage of its high-energy characteristics. Low-intensity ultrasound, which produces low energy, can be used as a means to regulate the nervous system. The present review describes the current status of research on low-intensity transcranial ultrasound stimulation (LITUS) in the treatment of neurological disorders, such as epilepsy, essential tremor, depression, Parkinson's disease (PD), and Alzheimer's disease (AD). This review summarizes preclinical and clinical studies using LITUS to treat the aforementioned neurological disorders and discusses their underlying mechanisms.

NCAM regulates temporal specification of neural progenitor cells via profilin2 during corticogenesis.

The development of cerebral cortex requires spatially and temporally orchestrated proliferation, migration, and differentiation of neural progenitor cells (NPCs). The molecular mechanisms underlying cortical development are, however, not fully understood. The neural cell adhesion molecule (NCAM) has been suggested to play a role in corticogenesis. Here we show that NCAM is dynamically expressed in the developing cortex. NCAM expression in NPCs is highest in the neurogenic period and declines during the gliogenic period. In mice bearing an NPC-specific NCAM deletion, proliferation of NPCs is reduced, and production of cortical neurons is delayed, while formation of cortical glia is advanced. Mechanistically, NCAM enhances actin polymerization in NPCs by interacting with actin-associated protein profilin2. NCAM-dependent regulation of NPCs is blocked by mutations in the profilin2 binding site. Thus, NCAM plays an essential role in NPC proliferation and fate decision during cortical development by regulating profilin2-dependent actin polymerization.

[Professor LI Xiao-ning's experience for post-stroke dysphagia treated with penetrating-needling and swallowing technique of acupuncture].

Professor LI Xiaoning's experience for post-stroke dysphagia treated with penetrating-needling and swallowing technique of acupuncture is summarized in this paper. The key pathogenesis of this disease is dysfunction of zangfu organs, impairment of the house of mental activity and dysfunction of meridian sinew. Innovatively, the anatomic structure related to swallowing is divided into three zones. Based on the distributions of heart, kidney and stomach meridians on the neck, three lines are determined. Hence, the theory of "three-zone and three-line" as well as the penetrating-needling and swallowing technique of acupuncture are put forward. In this paper, the theoretic evidences of penetrating-needling and swallowing technique of acupuncture, point selection and manipulation in treatment of post-stroke dysphagia are introduced.

Progression and status of antiviral monitoring in patients with chronic hepatitis B: From HBsAg to HBV RNA.

As alternative indexes of hepatitis B virus (HBV), covalently closed circular DNA (cccDNA) transcriptional activity, hepatitis B surface antigen (HBsAg), hepatitis B core-related antigen (HBcrAg), and peripheral blood RNA known as pgRNA, have been advocated as novel serum markers for prediction of prognosis and treatment response in chronic hepatitis B (CHB). Since the availability of commercial quantitative assays of HBsAg in 2011, HBsAg has been widely used for predicting treatment response of patients with CHB. Patients who received interferon therapy have shown a sharper reduction of HBsAg level than those who received nucleoside drug (NAs) therapy. Upon peginterferon treatment, sustained responders have presented a larger reduction of HBsAg level than the non-responders. An absence of HBsAg decline, together with < 2log reduction in HBV DNA at week 12, can serve as a stopping rule in HBsAg-negative patients infected with genotype D HBV. A sharp reduction of HBsAg titer in the NAs therapy is a predictor of HBsAg clearance in long-term treatment. HBcrAg, which consists of three species of related proteins sharing an identical 149 amino acid sequence, including HbcAg, hepatitis B e antigen (HBeAg), and a truncated 22-kDa precore protein, is still detectable in situations where serum HBV DNA levels become undetectable or HBsAg loss is achieved. Therefore, HBcrAg remains a measurable serum marker to correlate with cccDNA in this situation. The decline in HBcrAg has been observed with NAs therapy and the pattern of decline might provide prognostic information on the risk of HBV post-treatment reactivation. Peripheral blood RNA, which is known as pgRNA, directly derives from cccDNA and reflects intrahepatic cccDNA level. Quantitative pgRNA has been suggested to be helpful in CHB management. However, commercial quantitative assays are lacking. Additionally, the use of simultaneous and continuous clearance of HBV RNA and HBV DNA in serum has been suggested to be a safe stopping rule of NAs therapy for patients with CHB. However, clinical studies of large sample sizes are needed to prove the feasibility and significance of using serum HBV RNA as the assessment standard of antiviral therapy in CHB and the safety of the stopping rule in clinics.

[Electroacupuncture Improves Limb Locomotor Function Possibly by Suppressing Rho-ROCK â ¡ Pathway Related Factors in Anterior Horns of Spinal Cord in Rats with Acute Spinal Cord Injury].

OBJECTIVE: To observe the effect of electroacupuncture (EA) of "Jiaji" (EX-B 2) on limb locomotor function and expression of Ras homolog gene family member A (RhoA), Rho-associated kinase Ⅱ (ROCK Ⅱ) and myosin light chain (MLC) proteins in the anterior horn of spinal cord in acute spinal cord injury (ASCI) rats, so as to explore its mechanisms under-lying improvement of SCI-induced limb locomotor dysfunction. METHODS: Forty-eight female Wistar rats were randomly divided into sham operation (sham), ASCI model (model), EA EX-B 2 (EA) and ROCK inhibitor (Fasudil) groups which were further divided into 14 d and 28 d subgroups (n=6 in each). The ASCI model was made by using weight drop striking method. Three hours after modeling, EA (100 Hz, 0.4, 0.6 mA) was applied to EX-B 2 (T 9, T 11) for 30 min, once daily for 14 d and 28 d, respectively. The ROCK inhibitor (hydrochloride Fasudil, 10 mg/kg) was administrated by intraperitoneal injection immediately after modeling, once a day, continuously for 14 d or 28 d. The expression of RhoA, ROCK Ⅱ and MLC proteins in the spinal cord anterior horn tissue (T 10) was detected by immunohistochemistry. The rats' hindlimb locomotor function was assessed according to Basso, Beattie and Bresnahan (BBB) locomotor rating scale (21-points). RESULTS: After ASCI, the BBB scores were significantly lower in the model group than in the sham group on day 14 and 28 (P<0.05), and obviously higher in the EA and inhibitor groups than in the model group (P<0.05), suggesting an improvement of the hindlimb locomotor function after EA intervention or suppression of ROCK. Immunohistochemical results indicated that the numbers of RhoA, ROCK Ⅱ and MLC immune-reaction positive cells in the anterior horn of spinal cord were significantly more in the model group than in the sham group (P<0.05), and remarkably decreased in both EA and inhibitor groups on day 14 and 28 relevant to the model group (P<0.05). The therapeutic effects of EA were markedly weaker than those of inhibitor Fasudil in up-regulating BBB score and down-regulating the number of RhoA, ROCK Ⅱ and MLC positive cells (P<0.05). CONCLUSION: EA of EX-B 2 can improve the hindlimb locomotor function in ASCI rats, which may be associated with its effect in down-regulating the expression of RhoA, ROCK Ⅱ and MLC proteins (i.e., inhibiting the RhoA/ROCK signaling pathway) in the anterior horn of spinal cord.

Four Hybrid Flavan-Chalcones, Caesalpinnone A Possessing a 10,11-Dioxatricyclic [5.3.3.01,6]Tridecane-Bridged System and Caesalpinflavans A-C from Caesalpinia enneaphylla.

Caesalpinnone A (1), an unprecedented hybrid of flavan and chalcone, possessing a 10,11-dioxatricyclic [5.3.3.01,6]tridecane-bridged system, and caesalpinflavans A-C (2-4), three new hybrid flavan-chalcones, were isolated from the twigs and leaves of Caesalpinia enneaphylla. Their structures were elucidated by a combination of spectroscopic analyses and single-crystal X-ray diffraction. Caesalpinnone A showed the highest cytotoxicity against the HL-60, SMMC-7721, A-549, MCF-7, and SW-480 human tumor cell lines with an IC50 in the range of 0.54-0.87 µM.

Chemical constituents of Abies nukiangensis.

During a survey on chemical constituents of Abies nukiangensis, seven previously unreported compounds, including six triterpenes (1-6) and one phenol (7) were isolated and characterized, together with 37 known miscellaneous chemical constituents. The structures of compounds 1-7 were established mainly by extensive analysis of the 1D and 2D NMR, as well as HRMS data. The absolute configurations of compounds 1 and 8 were confirmed unambiguously by the Cu-Kα X-ray crystallography. Compounds 3 and 8-10 showed significant anti-hepatitis C virus effects with EC50 values of 3.73, 2.67, 1.33 and 2.25µM, respectively.

Changes in circulating Foxp3(+) regulatory T cells and interleukin-17-producing T helper cells during HBV-related acute-on-chronic liver failure.

AIM: To longitudinally investigate cytokine gene expression and protein levels in Th17 and Treg cells, to observe T-cell phenotypes during hepatitis B virus (HBV)-related acute-on-chronic liver failure (ACHBLF) and to analyze changes in Th17 and Treg phenotypes during disease progression. METHODS: We measured the expression of seven Th17/Treg differentiation-related genes and serum concentrations of the corresponding cytokines in 18 ACHBLF, 18 chronic hepatitis B (CHB) disease controls and 10 healthy controls (HCs) by real-time quantitative PCR and enzyme linked immunosorbent assay. Peripheral Th17 and Treg cell frequencies were analyzed by flow cytometry. RESULTS: From the onset of ACHBLF, patients presented with a conductive Th17 differentiation cytokine environment accompanied by high Th17 frequency and high serum IL-17 levels, which were sustained throughout the disease course. The Treg-related cytokine IL-2 and Foxp3 were also up-regulated from disease onset, and Foxp3 gene expression showed a gradually increasing trend during ACHBLF. The circular phenotype of Treg and Th17 cells showed changes from the onset of ACHGLF. At disease onset, Th17 frequency increased significantly compared with both CHB and HCs, but Treg cell frequency decreased significantly compared with CHB. During the ACHBLF event, Th17 frequency remained higher compared with HCs, but decreased sharply from the peak point to the recovery point; Treg cell frequency increased gradually during the ACHBLF event. Treg and Th17 cell counts correlated with ACHBLF development; in all patients, serum IL-17 levels significantly correlated with patient serum ALT levels. In survivors, Th17 frequency at the onset point and the Treg to Th17 ratio at the peak point correlated with the patient's model for end stage liver disease (MELD) plus sodium (MELD-Na) score. The Treg to Th17 ratio and the Th17 frequency at onset were significant predictors of patient survival. Low Treg/Th17 cell ratios at the onset predicted poor survival. Survivors exhibited an initial decrease in the circulating Treg/Th17 ratio from the onset to the peak time, and subsequently displayed a continuous increase. CONCLUSION: Treg and Th17 cells showed changes in genes, protein levels and T cell phenotypes during ACHBLF events. An increased Treg/Th17 ratio was associated with the survival of ACHBLF patients.

Viral infection parameters not nucleoside analogue itself correlates with host immunity in nucleoside analogue therapy for chronic hepatitis B.

AIM: To determine the relationship between host immunity and the characteristics of viral infection or nucleoside analogues (NAs) themselves in patients with chronic hepatitis B (CHB) receiving NA therapy. METHODS: Fifty-two hepatitis B envelope antigen (HBeAg) positive CHB patients were enrolled and divided equally into two groups. One group received telbivudine (LDT, 600 mg/d), and the other group received lamivudine (LAM, 100 mg/d). Clinical, virological and immunological parameters were assessed at the baseline and at 4, 12, 24, 36 and 48 wk. RESULTS: Both groups achieved significant hepatitis B virus (HBV) replication inhibition and alanine aminotransferase normalization at 48 wk. At the baseline, compared to healthy controls, CHB patients had a lower circulating CD8 T cell frequency (29.44% ± 11.55% vs 37.17% ± 7.30%, P = 0.03) and higher frequencies of programmed death 1 positive CD8 T cells (PD-1+ CD8 T) (16.48% ± 10.82% vs 7.02% ± 3.62%, P = 0.0001) and CD4+ CD25+ FoxP3+ T regulatory cells (Tregs) (23.64% ± 9.38% vs 13.60% ± 6.06%, P = 0.001). On therapy, at the beginning 24 wk with the levels of hepatitis B virus deoxyribonucleic acid (HBV DNA) and HBeAg declining, the frequencies of PD-1+ CD8 T cells and Treg cells gradually and significantly declined at 12 and 24 wk in both therapy groups. At treatment week 4, patients treated with LDT had a lower frequency of PD-1+ CD8 T cells compared to patients treated with LAM (10.08% ± 6.83% vs 20.51% ± 20.96%, P = 0.02). The frequency of PD-1+ CD8 T cells in all of the CHB patients was significantly correlated with both the HBV DNA level (r = 0.45, P = 0.01) and HBeAg level (r = 0.47, P = 0.01) at treatment week 24, but the frequency of Treg cells was only significantly correlated with the HBeAg level (r = 0.44,P = 0.02). Furthermore, the ability of CD8 T cells to secrete pro-inflammatory cytokines was partially restored after 24 wk of therapy. CONCLUSION: NA-mediated HBV suppression could down-regulate the production of negative regulators of host immunity during the first 24 wk of therapy and could partially restore the ability of CD8 T cells to secrete pro-inflammatory cytokines. This immune modulating response may be correlated with the levels of both HBV DNA and HBeAg.

Natural course of chronic hepatitis B is characterized by changing patterns of programmed death type-1 of CD8-positive T cells.

AIM: To investigate if and how programmed death type-1 (PD-1) expression affects the natural course of hepatitis B virus (HBV) infection. METHODS: Sixty-four patients in different natural stages of chronic HBV infection were enrolled in this study. PD-1 expression in total T cells was detected by flow cytometry. Levels of total CD8+ T cell responses and proliferation in relation to PD-1 expression levels were analyzed with intracellular staining and PD-1/PD-L1 blockage. RESULTS: The PD-1 expression in T cells was dynamically changed during the natural course of chronic HBV infection, did not significantly increase in the immune tolerance phase, and returned to normal in the inactive virus carrier stage. Blockage of the PD-1/PD-L1 pathway could not affect the T-cell response in the immune tolerance and inactive virus carrier stages of chronic HBV infection. However, it could significantly restore the T-cell response in the immune clearance stage of chronic HBV infection. Furthermore, the PD-1 expression level in T cells was associated with the alanine aminotransferase level during the immune clearance stage of chronic HBV infection. CONCLUSION: The PD-l/PD-L1 pathway plays a different role in T-cell response during the natural course of chronic HBV infection.