Soluble fibrinogen-like protein 2 (sFGL2), a secretory protein expressed by regulatory T cells (Tregs) with immunosuppressive activity, is highly expressed in both the peripheral blood and tumor tissue of patients with hepatocellular carcinoma (HCC); however, sFGL2 function in HCC remains largely unknown. Here, we elucidated the potential role of sFGL2 in HCC progression. T cells, dendritic cells (DCs), and related cytokines in the tumor microenvironment were comparatively analyzed in BALB/c and C57BL/6 mice bearing transplanted hepatomas harboring Fgl2-knockout or receiving sFGL2-antibody treatment. Additionally, the effects of sFGL2 on DCs and T cells were evaluated in vivo and ex vivo. The growth of both subcutaneously and orthotopically transplanted hepatomas was inhibited in Fgl2-knockout mice and those treated with the sFGL2 antibody, respectively, as compared with controls. Moreover, sFGL2 depletion enhanced the proportion and cytotoxicity of cytotoxic T cells, promoted DC maturation, and improved DC activity to proliferate T cells in the tumor microenvironment. Furthermore, we detected lower levels of interleukin (IL)-35 in both types of transplanted hepatomas and higher level of IL-6 in orthotopically transplanted hepatomas following sFGL2 depletion. Mechanistically, we found that sFGL2 impaired bone-marrow-derived DC (BMDCs) function by inhibiting phosphorylation of Akt, nuclear factor-kappaB, cAMP response element binding protein, and p38 and downregulating the expression of major histocompatibility complex II, CD40, CD80, CD86, and CD83 on BMDCs in vitro. Our data suggest that sFGL2 promotes hepatoma growth by attenuating DC activity and subsequent CD8+ T cell cytotoxicity, suggesting sFGL2 as a novel potential therapeutic target for HCC treatment.
Endothelin receptors (ETRs) are activated by vasoactive peptide endothelins and involved in the pathogenesis of hepatic fibrosis. However, less is known about the role of ETRs in Schistosoma (S.) japonicum-induced hepatic fibrosis. Here, we show that the expression of ETRs is markedly enhanced in the liver and spleen tissues of patients with schistosome-induced fibrosis, as well as in murine models. Additional analyses have indicated that the expression levels of ETRs in schistosomiasis patients are highly correlated with the portal vein and spleen thickness diameter, both of which represent the severity of fibrosis. Splenomegaly is a characteristic symptom of schistosome infection, and splenic abnormality may promote the progression of hepatic fibrosis. We further demonstrate that elevated levels of ETRs are predominantly expressed on splenic B cells in spleen tissues during infection. Importantly, using a well-studied model of human schistosomiasis, we demonstrate that endothelin receptor antagonists can partially reverse schistosome-induced hepatic fibrosis by suppressing the activation of splenic B cells characterized by interleukin-10 (IL-10) secretion and regulatory T (Treg) cell-inducing capacity. Our study provides insights into the mechanisms by which ETRs regulate schistosomiasis hepatic fibrosis and highlights the potential of endothelin receptor antagonist as a therapeutic intervention for fibrotic diseases. Schistosomiasis is a serious but neglected tropical infectious disease. which can lead to hepatic fibrosis and death. To date, there are still no approved antifibrotic therapies. Hepatic fibrosis results in portal hypertension and variceal bleeding, and it is the primary cause of mortality from schistosomiasis. Splenomegaly and hypersplenism can manifest following the development of portal hypertension. Accumulating evidence suggests that the spleen plays a critical role in the development of hepatic fibrosis. In this study, using Schistosoma (S.) japonicum in both humans and mice, we show that progressive hepatic schistosomiasis caused elevation of endothelin receptors (ETRs) both in liver and spleen tissues, and the endothelin receptor-producing cells are mainly located in splenic B cells. More importantly, we demonstrate that endothelin receptor antagonists can partially reverse schistosome-induced hepatic fibrosis by suppressing the activation of splenic B cells during infection. Thus, our study highlights the potential of endothelin receptor antagonist as a therapeutic intervention for schistosomiasis and other fibrotic diseases.
Introduction Evaluation of cirrhosis appears to be easily overlooked in the clinic for the HBsAg-negative (hepatitis B surface antigen-negative) and HBcAb-positive (hepatitis B core antibody-positive) population. Herein, we determine the prevalence of cirrhosis/advanced fibrosis among HBsAg-negative/HBcAb-positive US adults. Methods Data came from the National Health and Nutrition Examination Survey (NHANES) 2001–2018. A total of 3115 HBsAg-negative/HBcAb-positive US adults were enrolled in this study. We assessed cirrhosis by using the Fibrosis-4 (FIB-4) and aspartate aminotransferase to platelet ratio index (APRI) score. Results Out of 50,201 NHANES adults, 45,087 were tested for HBcAb/HBsAg, of whom 3115 met the inclusion criteria (HBsAg-negative/HBcAb-positive with available data for FIB-4/APRI). The weighted proportion of HBsAg-negative/HBcAb-positive among US adults was 4.46% (95% CI 4.17–4.75%), affecting 9.87 million US adults. According to the results of the FIB-4, the weighted prevalence of cirrhosis/advanced fibrosis among HBsAg-negative/HBcAb-positive US adults was 3.76% (95% CI 2.80–4.72%), which corresponds to 371,112 (95% CI 276,360–465,864) HBsAg-negative/HBcAb-positive American adults who had already developed cirrhosis. Among those, cirrhosis/advanced fibrosis in the HBsAb-negative (hepatitis B surface antibody) group (6.28%, 95% CI 4.10–8.45%) was significantly higher than in the HBsAb-positive group (3.08%, 95% CI 2.07–4.08%). Results were similar when APRI was used. Conclusion According to the FIB-4, 3.76% of HBsAg-negative and HBcAb-positive US adults had cirrhosis/advanced fibrosis, much higher than in the general population of the USA. Our data highlight the importance of cirrhosis screening in the HBsAg-negative/HBcAb-positive population to prevent advanced liver disease, especially in those who are HBsAb-negative.
Background: Schistosomiasis is a serious but neglected parasitic disease in humans that may lead to liver fibrosis and death. Activated hepatic stellate cells (HSCs) are the principal effectors that promote the accumulation of extracellular matrix (ECM) proteins during hepatic fibrosis. Aberrant microRNA-29 expression is involved in the development of fibrotic diseases. However, less is known about the role of miR-29 in Schistosoma japonicum (S. japonicum)-induced hepatic fibrosis. Methods: The levels of microRNA-29a-3p (miR-29a-3p) and Roundabout homolog 1 (Robo1) were examined in liver tissues during S. japonicum infection. The possible involvement of the miR-29a-3p-Robo1 signaling pathway was determined. We used MIR29A conditional knock-in mice and mice injected with an miR-29a-3p agomir to investigate the role of miR-29a-3p in schistosomiasis-induced hepatic fibrosis. The functional contributions of miR-29a-3p-Robo1 signaling in liver fibrosis and HSC activation were investigated using primary mouse HSCs and the human HSC cell line LX-2. Results: MiR-29a-3p was downregulated in humans and mice with schistosome-induced fibrosis, and Robo1 was upregulated in liver tissues. The miR-29a-3p targeted Robo1 and negatively regulated its expression. Additionally, the expression level of miR-29a-3p in schistosomiasis patients was highly correlated with the portal vein and spleen thickness diameter, which represent the severity of fibrosis. Furthermore, we demonstrated that efficient and sustained elevation of miR-29a-3p reversed schistosome-induced hepatic fibrosis. Notably, we showed that miR-29a-3p targeted Robo1 in HSCs to prevent the activation of HSCs during infection. Conclusions: Our results provide experimental and clinical evidence that the miR-29a-3p-Robo1 signaling pathway in HSCs plays an important role in the development of hepatic fibrosis. Therefore, our study highlights the potential of miR-29a-3p as a therapeutic intervention for schistosomiasis and other fibrotic diseases. Graphical
8 February 2023 in Infectious Diseases and Therapy
Introduction Surveillance programs after hepatitis B surface antigen (HBsAg) loss are not yet well established, and the role of hepatitis B surface antibodies (anti-HBs) remains controversial. We aimed to evaluate the risk factors for increased mortality and the association between anti-HBs and all-cause and cause-specific mortality in a representative US (United States) population of patients with resolved HBV (Hepatitis B virus) infections. Methods Data were taken from the US National Health and Nutrition Examination Survey (NHANES) 1999–2018. A total of 3455 US adults with resolved HBV infection [defined as hepatitis B surface antigen (HBsAg) negative/anti-hepatitis B core antigen (anti-HBc) positive] were enrolled in this study. The primary outcome measures were all-cause and cause-specific mortality from baseline until 31 December 2019. Results During a mean follow-up of 10.3 years, 741 deaths occurred. Age, race, marital status, smoking status, physical activity level, and presence of cirrhosis, diabetes, cardiovascular diseases, chronic obstructive pulmonary diseases, cancer, and anti-HBs were significant factors for increased mortality, and a nomogram tool was developed and validated for the risk stratification of mortality. Compared with participants who were anti-HBs positive, those who were anti-HBs negative had a 23% (hazard ratio 1.23, 95% CI 1.02–1.46) higher risk of all-cause mortality in NHANES 1999–2018. For cause-specific mortality, the fully adjusted hazard ratios of participants who were anti-HBs negative were 0.71 (95% CI 0.48–1.06) for heart disease, 1.44 (95% CI 1.01–2.05) for cancer, and 1.44 (95% CI 1.13–1.83) for other conditions, compared to those of participants who were anti-HBs positive. Conclusions Among US adults with resolved HBV infections, anti-HBs-negative status was associated with an increased risk of death from all causes and cancer, implying that the role of anti-HBs in resolved HBV infection should not be ignored. On the public health level, more rigorous surveillance was needed for populations of individuals who were isolated anti-HBc positive.