FoxP3- Tr1 Cell in Generalized Myasthenia Gravis and Its Relationship With the Anti-AChR Antibody and Immunomodulatory Cytokines

Pro-inflammatory cytokines in myasthenia gravis: a systematic review and meta-analysis

BACKGROUND

Myasthenia gravis (MG) is an autoimmune neuromuscular disorder impacting muscle endplate components. Pro-inflammatory cytokines, particularly, might play pivotal roles in MG pathogenesis, influencing regulatory T cells and contributing to chronic inflammation. We did this systematic review and meta-analysis to address the conflicting results about pro-inflammatory cytokine profiles in MG.

METHODS

A thorough search was conducted in PubMed, Scopus, and Embase to find studies measuring interleukin (IL)-1 family (IL-1β, IL-18, IL-33, IL-36, IL-37), IL-6, and tumor necrosis factor-alpha (TNF-α) levels in MG patients' serum and controls. Selection criteria encompassed various MG types, including ocular and generalized, with and without thymoma, and acetylcholine receptor (AChR) antibody-positive and negative.

RESULTS

Of the 1843 identified studies, 16 met the inclusion criteria. The meta-analysis revealed a significant increase in serum TNF-α, IL-1β, and IL-33 level in MG patients compared to controls. The included studies also implied elevated levels of IL-18 in people with MG compared to controls and elevated levels of IL-18 and IL-33 in generalized MG compared to ocular MG.

CONCLUSION

Our study highlights the altered profiles of pro-inflammatory cytokines in MG.

Type 2 hypersensitivity disorders, including systemic lupus erythematosus, Sjögren's syndrome, Graves' disease, myasthenia gravis, immune thrombocytopenia, autoimmune hemolytic anemia, dermatomyositis, and graft-versus-host disease, are THαβ-dominant autoimmune diseases

The THαβ host immunological pathway contributes to the response to infectious particles (viruses and prions). Furthermore, there is increasing evidence for associations between autoimmune diseases, and particularly type 2 hypersensitivity disorders, and the THαβ immune response. For example, patients with systemic lupus erythematosus often produce anti-double stranded DNA antibodies and anti-nuclear antibodies and show elevated levels of type 1 interferons, type 3 interferons, interleukin-10, IgG1, and IgA1 throughout the disease course. These cytokines and antibody isotypes are associated with the THαβ host immunological pathway. Similarly, the type 2 hypersensitivity disorders myasthenia gravis, Graves' disease, graft-versus-host disease, autoimmune hemolytic anemia, immune thrombocytopenia, dermatomyositis, and Sjögren's syndrome have also been linked to the THαβ pathway. Considering the potential associations between these diseases and dysregulated THαβ immune responses, therapeutic strategies such as anti-interleukin-10 or anti-interferon α/β could be explored for effective management.

Oral Microbiota Profile in a Group of Anti-AChR Antibody–Positive Myasthenia Gravis Patients

Myasthenia gravis (MG) is an autoimmune disorder caused by autoantibodies directed against the postsynaptic membrane at the neuromuscular junction. Perturbation of gut microbiota is thought to contribute to the development of MG, as reflected by fecal metabolomic signatures in humans, but there have been few studies on the relationship between oral microbiota profile and MG. The current study evaluated the correlation between oral microbiota composition and diversity and anti-acetylcholinereceptor (AChR) antibody–positive MG by comparing oral microbiota communities of patients (n = 20) and healthy controls (HCs; n = 20) by 16S rRNA gene sequencing. Principal coordinate analysis and Adonis analysis revealed significant differences in oral microflora profile between the twogroups. Compared to HCs, the abundance of the phyla Firmicutes and Actinobacteria and genera Streptococcus, Rothia, and Lachnoanerobaculum was significantly increased whereas that of phyla Proteobacteria and Spirochaetotaand genera Neisseria, Haemophilus, and Treponema was significantly decreased in MG patients. The Kyoto Encyclopedia of Genes and Genomes pathway analysis showed that the biosynthesis of ansamycins and amino acid metabolism pathways were altered in MG. These results indicate that oral microbiota composition is perturbed in patients with anti-AChR antibody–positive MG, providing new potential avenues for targeted therapeutic interventions.