Overview of the immunological mechanisms in hepatitis B virus reactivation:Implications for disease progression and management strategies

Hepatitis B virus(HBV)reactivation is a clinically significant challenge in disease management.This review explores the immunological mechanisms underlying HBV reactivation,emphasizing disease progression and management.It delves into host immune responses and reactivation’s delicate balance,spanning innate and adaptive immunity.Viral factors’disruption of this balance,as are interac-tions between viral antigens,immune cells,cytokine networks,and immune checkpoint pathways,are examined.Notably,the roles of T cells,natural killer cells,and antigen-presenting cells are discussed,highlighting their influence on disease progression.HBV reactivation’s impact on disease severity,hepatic flares,liver fibrosis progression,and hepatocellular carcinoma is detailed.Management strategies,including anti-viral and immunomodulatory approaches,are critically analyzed.The role of prophylactic anti-viral therapy during immunosuppressive treatments is explored alongside novel immunotherapeutic interventions to restore immune control and prevent reactivation.In conclusion,this compre-hensive review furnishes a holistic view of the immunological mechanisms that propel HBV reactivation.With a dedicated focus on understanding its implic-ations for disease progression and the prospects of efficient management stra-tegies,this article contributes significantly to the knowledge base.The more profound insights into the intricate interactions between viral elements and the immune system will inform evidence-based approaches,ultimately enhancing disease management and elevating patient outcomes.The dynamic landscape of management strategies is critically scrutinized,spanning anti-viral and immunomodulatory approaches.The role of prophylactic anti-viral therapy in preventing reactivation during immunosuppressive treatments and the potential of innovative immunotherapeutic interventions to restore immune control and proactively deter reactivation.

Ocular diseases: immunological and molecular mechanisms

Many factors, such as environmental, microbial and endogenous stress, antigen localization, can trigger the immunological events that affect the ending of the diverse spectrum of ocular disorders. Significant advances in understanding of immunological and molecular mechanisms have been researched to improve the diagnosis and therapy for patients with ocular inflammatory diseases. Some kinds of ocular diseases are inadequately responsive to current medications;therefore, immunotherapy may be a potential choice as an alternative or adjunctive treatment, even in the prophylactic setting. This article first provides an overview of the immunological and molecular mechanisms concerning several typical and common ocular diseases; second, the functions of immunological roles in some of systemic autoimmunity will be discussed; third, we will provide a summary of the mechanisms that dictate immune cell trafficking to ocular local microenvironment in response to inflammation.

Impact of SARS-CoV-2 on neuropsychiatric disorders

Evolving data show a variable expression of clinical neurological manifestations in patients suffering with coronavirus disease 2019(COVID-19)from early disease onset.The most frequent symptoms and signs are fatigue,dizziness,impaired consciousness,ageusia,anosmia,radicular pain,and headache,as well as others.Based on the high number of series of cases reported,there is evidence for the implication of the immune system in the pathological mechanism of COVID-19.Although the exact role of the immunological mechanism is not elucidated,two main mechanisms are suggested which implicate the direct effect of severe acute respiratory syndrome coronavirus 2 infection in the central nervous system and neuroinflammation.In the context of neurological manifestations associated with COVID-19,neuropsychiatric disorders show an exacerbation and are described by symptoms and signs such as depression,anxiety,mood alterations,psychosis,post-traumatic stress disorder,delirium,and cognitive impairment,which appear to be common in COVID-19 survivors.A worsened score on psychopathological measures is seen in those with a history of psychiatric comorbidities.We review the neuropsychiatric manifestations associated with COVID-19 and some critical aspects of the innate and adaptive immune system involved in mental health disorders occurring in COVID-19.

Allogeneic compact bone-derived mesenchymal stem cell transplantation increases survival of mice exposed to lethal total body irradiation： a potential immunological mechanism

Background Radiation-induced injury after accidental or therapeutic total body exposure to ionizing radiation has serious pathophysiological consequences,and currently no effective therapy exists.This study was designed to investigate whether transplantation of allogeneic murine compact bone derived-mesenchymal stem cells （CB-MSCs） could improve the survival of mice exposed to lethal dosage total body irradiation （TBI）,and to explore the potential immunoprotective role of MSCs.Methods BALB/c mice were treated with 8 Gy TBI,and then some were administered CB-MSCs isolated from C57BL/6 mice.Survival rates and body weight were analyzed for 14 days post-irradiation.At three days post-irradiation,we evaluated IFN-Y and IL-4 concentrations; CD4＋CD25＋Foxp3＋ regulatory T cell （Treg） percentage; CXCR3,CCR5,and CCR7 expressions on CD3＋T cells; and splenocyte T-bet and GATA-3 mRNA levels.CB-MSC effects on bone marrow hemopoiesis were assessed via colony-forming unit granulocyte/macrophage （CFU-GM） assay.Results After lethal TBI,compared to non-transplanted mice,CB-MSC-transplanted mice exhibited significantly increased survival,body weight,and CFU-GM counts of bone marrow cells （P＜0.05）,as well as higher Treg percentages,reduced IFN-Y,CXCR3 and CCR5 down-regulation,and CCR7 up-regulation.CB-MSC transplantation suppressed Th1 immunity.Irradiated splenocytes directly suppressed CFU-GM formation from bone marrow cells,and CB-MSC co-culture reversed this inhibition.Conclusion Allogeneic CB-MSC transplantation attenuated radiation-induced hematopoietic toxicity,and provided immunoprotection by alleviating lymphocyte-mediated CFU-GM inhibition,expanding Tregs,regulating T cell chemokine receptor expressions,and skewing the Th1/Th2 balance toward anti-inflammatory Th2 polarization.