The Plasticity of Immune Cell Response Complicates Dissecting the Underlying Pathology of Multiple Sclerosis

Multiple sclerosis (MS) is a neurodegenerative autoimmune disease characterized by the destruction of the myelin sheath of the neuronal axon in the central nervous system. Many risk factors, including environmental, epigenetic, genetic, and lifestyle factors, are responsible for the development of MS. It has long been thought that only adaptive immune cells, especially autoreactive T cells, are responsible for the pathophysiology; however, recent evidence has indicated that innate immune cells are also highly involved in disease initiation and progression. Here, we compile the available data regarding the role immune cells play in MS, drawn from both human and animal research. While T and B lymphocytes, chiefly enhance MS pathology, regulatory T cells (Tregs) may serve a more protective role, as can B cells, depending on context and location. Cells chiefly involved in innate immunity, including macrophages, microglia, astrocytes, dendritic cells, natural killer (NK) cells, eosinophils, and mast cells, play varied roles. In addition, there is evidence regarding the involvement of innate-like immune cells, such as γδ T cells, NKT cells, MAIT cells, and innate-like B cells as crucial contributors to MS pathophysiology. It is unclear which of these cell subsets are involved in the onset or progression of disease or in protective mechanisms due to their plastic nature, which can change their properties and functions depending on microenvironmental exposure and the response of neural networks in damage control. This highlights the need for a multipronged approach, combining stringently designed clinical data with carefully controlled in vitro and in vivo research findings, to identify the underlying mechanisms so that more effective therapeutics can be developed.

The role of oxidative stress and haematological parameters in relapsing-remitting multiple sclerosis in Kurdish population

BACKGROUND

Multiple sclerosis (MS), as a neurodegenerative disorder, exhibits inflammation and oxidative stress hallmarks.

OBJECTIVE

The research aims to know any disturbances in haematological parameters and antioxidant system of relapsing-remitting multiple sclerosis (RRMS) patients in the Kurdish population.

METHODS

A case-control research meeting following the McDonald criterion was conducted on 100 RRMS patients and 100 controls.

RESULTS

Lipid peroxidation products of malondialdehyde (MDA), erythrocyte sedimentation rate (ESR), and total leucocyte counts (TLCs) were increased significantly, but copper (Cu+2) and superoxide dismutase (SOD) were decreased significantly while nitric oxide metabolites (NOx) and lymphocyte were not changed significantly if compared with that of controls.

CONCLUSION

Findings from our study revealed that some defects were detected in haematological profiles in the Kurdish population and disturbance of immunological parameters. In addition, the utilization of Cu+2 supplement as an effective modality for RRMS patients may be beneficial.

The Influence of Reactive Oxygen Species in the Immune System and Pathogenesis of Multiple Sclerosis

Multiple roles have been indicated for reactive oxygen species (ROS) in the immune system in recent years. ROS have been extensively studied due to their ability to damage DNA and other subcellular structures. Noticeably, they have been identified as a pivotal second messenger for T-cell receptor signaling and T-cell activation and participate in antigen cross-presentation and chemotaxis. As an agent with direct toxic effects on cells, ROS lead to the initiation of the autoimmune response. Moreover, ROS levels are regulated by antioxidant systems, which include enzymatic and nonenzymatic antioxidants. Enzymatic antioxidants include superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase. Nonenzymatic antioxidants contain vitamins C, A, and E, glutathione, and thioredoxin. Particularly, cellular antioxidant systems have important functions in maintaining the redox system homeostasis. This review will discuss the significant roles of ROS generation and antioxidant systems under normal conditions, in the immune system, and pathogenesis of multiple sclerosis.

Important role of mast cells in multiple sclerosis

Autoimmunity is a disease that occurs when the body tissue is attacked by its own immune system. Multiple sclerosis (MS) is an autoimmune illness which triggers neurological progressive and persistent functions. MS is associated with an abnormal B-cell response and upregulation of T-cell reactivity against a multitude of antigens. Mast cells are the first line of the innate immune system and act by degranulating and secreting chemical mediators and cytokines. Their participation on the central nervous system has been recognized since the beginning of the last century. They have an important role in autoimmune disease, including MS where they mediate inflammation and demyelinization by presenting myelin antigens to T cells or disrupting the blood-brain barrier and permitting entry of inflammatory cells and cytokines. The participation of mast cells in MS is demonstrated by gene overexpression of chemical mediators and inflammatory cytokines. Here we report the relationship and involvement between mast cells and multiple sclerosis.

Impact of mast cells on multiple sclerosis: inhibitory effect of natalizumab

Mast cells (MCs) derive from a distinct precursor in the bone marrow and are predominantly found in tissues at the interface between the host and the external environment where they can secrete mediators without overt degranulation. Mast cells mature under local tissue microenvironmental factors and are necessary for the development of allergic reactions, through crosslinking of their surface receptors for IgE (FcεRI), leading to degranulation and the release of vasoactive, pro-inflammatory and nociceptive mediators that include histamine, pro-inflammatory and anti-inflammatory cytokines and proteolytic enzymes. Multiple sclerosis (MS) is an autoimmune disease characterized by inflammatory demylination within the central nervous system. MCs are involved in the pathogenesis of MS by generating various vasoactive mediators and cytokines and participate in the destruction of the myelin sheath and the neuronal cells. The process of the development of demyelinating plaques in MS is probably linked with the rupture of the blood-brain barrier by MC products. The effects of natalizumab, which is a very effective drug in reducing the annualized relapse rate and other relapse-based endpoints, are discussed. Here, we report the relationship between MCs and MS.