The development of alcoholic liver disease (ALD) can be attributed to many factors that cause damage to the liver and alter its functions. Data collected over the last 30 years strongly suggests that an immune compone...The development of alcoholic liver disease (ALD) can be attributed to many factors that cause damage to the liver and alter its functions. Data collected over the last 30 years strongly suggests that an immune component may be involved in the onset of this disease. This is best evidenced by the detection of circulating autoantibodies, infiltration of immune cells in the liver, and the detection of hepatic aldehyde modified proteins in patients with ALD. Experimentally, there are numerous immune responses that occur when proteins are modified with the metabolites of ethanol. These products are formed in response to the high oxidative state of the liver during ethanol metabolism, causing the release of many inflammatory processes and potential of necrosis or apoptosis of liver cells. Should cellular proteins become modified with these reactive alcohol metabolites and be recognized by the immune system, then immune responses may be initiated. Therefore, it was the purpose of this article to shed some insight into how the immune system is involved in the development and/or progression of ALD.展开更多
Cytokines are involved in directing the activation of natural killer (NK) cells. NK cells are involved in the recognition of cells that have been altered; thus they do not recognize specific insults to the host, but...Cytokines are involved in directing the activation of natural killer (NK) cells. NK cells are involved in the recognition of cells that have been altered; thus they do not recognize specific insults to the host, but when activated, are capable of destroying infected cells directly, as well as promoting the recruitment and response of the other components of the immune system by the release of cytokines and chemokines. It is these properties that have made NK cells a critical part of innate immunity and adaptive immunity, and they play a principal role linking innate and adaptive immunity by the recruitment of an adaptive immune response to an innate immune reaction.展开更多
AIM: To evaluate plasma levels of nitrite/nitrate (NOx), soluble Pas (spas) antigen, tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6) in patients with compensated and acute decompensated cirrhosi...AIM: To evaluate plasma levels of nitrite/nitrate (NOx), soluble Pas (spas) antigen, tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6) in patients with compensated and acute decompensated cirrhosis and to evaluate mediators causing acute decompensation in liver cirrhosis, METHODS: This prospective study was conducted in the medical intensive care unit of an academic tertiary center, Fifty-five patients with acute decompensation (gastrointestinal hemorrhage, encephalopathy, hydropic decompensation) and twenty-five patients with compensated liver drrhosis were included, Blood samples were taken for analyses of spas, Nox, IL-6, TNF-α, Liver enzymes and kidney functions were also tested, RESULTS: In patients with acute decompensation, plasma spas levels were higher than in non-decompensated patients (15305 ± 4646 vs 12458± 4322 pg/mL, P 〈 0.05). This was also true for the subgroup of patients with alcoholic liver cirrhosis (P 〈 0.05). The other mediators were not different and none of the parameters predicted survival, except for ALT (alanine-aminotransferase). In patients with portal-hypertension-induced acute hemorrhage, NOx levels were significantly lower than in patients with other forms of decompensation (70.8 ± 48.3 vs 112.9 ± 74.9 pg/mL, P 〈 0.05). When NOx levels were normalized to creatinine levels, the difference disappeared. IL-6, TNF-α and spas were not different between bleeders and non-bleeders. In decompensated patients spas, IL-6 and NOx levels correlated positively with creatinine levels, while IL-6 levels were dependent on Child class. CONCLUSION: In acute decompensated cirrhotic patients sPas is increased, suggesting a role of apoptosis in this process and patients with acute bleeding have lower NOx levels, However, in this acute complex clinical situation, kidney function seems to have a predominant influence on mediator levels,展开更多
Loss of self-tolerance and expansion of auto-reactive lymphocytes are the basis for autoimmunity. Apoptosis and the rapid clearance of apoptotic cells by phagocytes usually occur as coordinated processes that ensure r...Loss of self-tolerance and expansion of auto-reactive lymphocytes are the basis for autoimmunity. Apoptosis and the rapid clearance of apoptotic cells by phagocytes usually occur as coordinated processes that ensure regulated cellularity and stress response with non-pathological outcomes. Defects in clearance of apoptotic ceils would contribute to the generation of self-reactive lymphocytes, which drive autoimmune disorders such as rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). The IL-12 family of cytokines (IL-12, IL-23, and IL-27) and IL-10 are produced by phagocytic macrophages and play critical roles in the regulation of antigen-presenting cells (APCs) and effector lymphocytes during an immune response to pathogens. Inappropriate expression of these cytokines and their dysregulated activities have been strongly implicated in the pathogenesis of several autoimmune diseases. The production of pro- and anti-inflammatory cytokines by phagocytic APCs is delicately regulated during the ingestion of apoptotic cells as part of an intrinsic mechanism to prevent inflammatory autoimmune reactions. How apoptotic cell-derived signals regulate cytokine production is poorly understood. A recent study by our group demonstrated that phagocytosis of apoptotic cells by activated macrophages results in strong inhibition of IL-12 p35 gene expression by activating a novel transcription repressor, which we named GC-binding protein (GC-BP), through tyrosine dephosphorylation. We are also beginning to understand the molecular mechanisms underlying apoptotic cell-triggered production of IL-10 by phagocytes. These studies will help to elucidate some novel immune regulatory mechanisms and explore the regulation of immune responses to autoantigens with potentials to discover new therapeutic targets for the treatment of autoimmune disorders.展开更多
文摘The development of alcoholic liver disease (ALD) can be attributed to many factors that cause damage to the liver and alter its functions. Data collected over the last 30 years strongly suggests that an immune component may be involved in the onset of this disease. This is best evidenced by the detection of circulating autoantibodies, infiltration of immune cells in the liver, and the detection of hepatic aldehyde modified proteins in patients with ALD. Experimentally, there are numerous immune responses that occur when proteins are modified with the metabolites of ethanol. These products are formed in response to the high oxidative state of the liver during ethanol metabolism, causing the release of many inflammatory processes and potential of necrosis or apoptosis of liver cells. Should cellular proteins become modified with these reactive alcohol metabolites and be recognized by the immune system, then immune responses may be initiated. Therefore, it was the purpose of this article to shed some insight into how the immune system is involved in the development and/or progression of ALD.
文摘Cytokines are involved in directing the activation of natural killer (NK) cells. NK cells are involved in the recognition of cells that have been altered; thus they do not recognize specific insults to the host, but when activated, are capable of destroying infected cells directly, as well as promoting the recruitment and response of the other components of the immune system by the release of cytokines and chemokines. It is these properties that have made NK cells a critical part of innate immunity and adaptive immunity, and they play a principal role linking innate and adaptive immunity by the recruitment of an adaptive immune response to an innate immune reaction.
文摘AIM: To evaluate plasma levels of nitrite/nitrate (NOx), soluble Pas (spas) antigen, tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6) in patients with compensated and acute decompensated cirrhosis and to evaluate mediators causing acute decompensation in liver cirrhosis, METHODS: This prospective study was conducted in the medical intensive care unit of an academic tertiary center, Fifty-five patients with acute decompensation (gastrointestinal hemorrhage, encephalopathy, hydropic decompensation) and twenty-five patients with compensated liver drrhosis were included, Blood samples were taken for analyses of spas, Nox, IL-6, TNF-α, Liver enzymes and kidney functions were also tested, RESULTS: In patients with acute decompensation, plasma spas levels were higher than in non-decompensated patients (15305 ± 4646 vs 12458± 4322 pg/mL, P 〈 0.05). This was also true for the subgroup of patients with alcoholic liver cirrhosis (P 〈 0.05). The other mediators were not different and none of the parameters predicted survival, except for ALT (alanine-aminotransferase). In patients with portal-hypertension-induced acute hemorrhage, NOx levels were significantly lower than in patients with other forms of decompensation (70.8 ± 48.3 vs 112.9 ± 74.9 pg/mL, P 〈 0.05). When NOx levels were normalized to creatinine levels, the difference disappeared. IL-6, TNF-α and spas were not different between bleeders and non-bleeders. In decompensated patients spas, IL-6 and NOx levels correlated positively with creatinine levels, while IL-6 levels were dependent on Child class. CONCLUSION: In acute decompensated cirrhotic patients sPas is increased, suggesting a role of apoptosis in this process and patients with acute bleeding have lower NOx levels, However, in this acute complex clinical situation, kidney function seems to have a predominant influence on mediator levels,
文摘Loss of self-tolerance and expansion of auto-reactive lymphocytes are the basis for autoimmunity. Apoptosis and the rapid clearance of apoptotic cells by phagocytes usually occur as coordinated processes that ensure regulated cellularity and stress response with non-pathological outcomes. Defects in clearance of apoptotic ceils would contribute to the generation of self-reactive lymphocytes, which drive autoimmune disorders such as rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). The IL-12 family of cytokines (IL-12, IL-23, and IL-27) and IL-10 are produced by phagocytic macrophages and play critical roles in the regulation of antigen-presenting cells (APCs) and effector lymphocytes during an immune response to pathogens. Inappropriate expression of these cytokines and their dysregulated activities have been strongly implicated in the pathogenesis of several autoimmune diseases. The production of pro- and anti-inflammatory cytokines by phagocytic APCs is delicately regulated during the ingestion of apoptotic cells as part of an intrinsic mechanism to prevent inflammatory autoimmune reactions. How apoptotic cell-derived signals regulate cytokine production is poorly understood. A recent study by our group demonstrated that phagocytosis of apoptotic cells by activated macrophages results in strong inhibition of IL-12 p35 gene expression by activating a novel transcription repressor, which we named GC-binding protein (GC-BP), through tyrosine dephosphorylation. We are also beginning to understand the molecular mechanisms underlying apoptotic cell-triggered production of IL-10 by phagocytes. These studies will help to elucidate some novel immune regulatory mechanisms and explore the regulation of immune responses to autoantigens with potentials to discover new therapeutic targets for the treatment of autoimmune disorders.