Histiocytic neoplasms are rare diseases involving macrophages, dendritic cells, and monocytes. They include Langer‑ hans cell histiocytosis (LCH), Erdheim-Chester disease (ECD), Rosai-Dorfman disease (RDD), juvenile xanthogranuloma (JXG), and histiocytic sarcoma. Histiocytic neoplasms are characterized by varied clinical courses and prognoses, necessitating a nuanced understanding of their classification, epidemiology, and clinical manifestations. Genetic studies have revealed somatic mutations, predominantly in the MAPK pathway, suggesting a clonal neoplastic nature.This review covers the current understanding of histiocytic neoplasms, molecular pathophysiology, with a particular focus on mutations in genes such as BRAF, MAP2K1, and the PI3K-AKT signaling pathways, and evolving treatment strategies, especially focusing on LCH, ECD, RDD, and JXG. The treatment landscape has evolved with advancements in targeted therapies. BRAF inhibitors, such as vemurafenib and dabrafenib, have shown efficacy, especially in highrisk LCH cases; however, challenges remain, including relapse post-treatment discontinuation, and adverse effects.MEK inhibitors have also demonstrated effectiveness, and cobimetinib has recently been approved for use in adults.Further research is required to determine the optimal treatment duration and strategies for managing therapy inter‑ ruptions. Advancements in molecular genetics and targeted therapies have revolutionized the management of histio‑ cytic neoplasms. However, ongoing research is crucial for optimizing patient outcomes.

Type 1 diabetes (T1D) is a chronic autoimmune disease characterized by the destruction of insulin-producing beta-cells in the pancreas.Genetic variations within the major histocompatibility complex (MHC) significantly influence the development of T1D, with diseaseprogression often indicated by the presence of autoantibodies. Until recently, insulin therapy was the sole treatment for T1D. However, in 2022, the Food and Drug Administration approved teplizumab, an anti-CD3 monoclonal antibody, as a novel immunomodulatory therapy to delay the onset of T1D. Various immunologic agents, including anti-CD antibodies and anti-cytokine autoantibodies, have been investigated across various stages of T1D in clinical trials. This article examines the current status of drug development for theprevention and treatment of T1D and summarizes key studies that aimed at delaying the onset of T1D using these agents. While effortsto halt or prevent the disease prior to clinical diagnosis have yielded limited success, post-diagnosis interventions have shown promising potential in slowing disease progression by preserving beta-cell function. Further investigation into long-term clinical outcomes related to the delay of T1D onset is necessary, and ongoing studies require extended follow-up to assess their full potential.

Histiocytic neoplasms are rare diseases involving macrophages, dendritic cells, and monocytes. They include Langer‑ hans cell histiocytosis (LCH), Erdheim-Chester disease (ECD), Rosai-Dorfman disease (RDD), juvenile xanthogranuloma (JXG), and histiocytic sarcoma. Histiocytic neoplasms are characterized by varied clinical courses and prognoses, necessitating a nuanced understanding of their classification, epidemiology, and clinical manifestations. Genetic studies have revealed somatic mutations, predominantly in the MAPK pathway, suggesting a clonal neoplastic nature.This review covers the current understanding of histiocytic neoplasms, molecular pathophysiology, with a particular focus on mutations in genes such as BRAF, MAP2K1, and the PI3K-AKT signaling pathways, and evolving treatment strategies, especially focusing on LCH, ECD, RDD, and JXG. The treatment landscape has evolved with advancements in targeted therapies. BRAF inhibitors, such as vemurafenib and dabrafenib, have shown efficacy, especially in highrisk LCH cases; however, challenges remain, including relapse post-treatment discontinuation, and adverse effects.MEK inhibitors have also demonstrated effectiveness, and cobimetinib has recently been approved for use in adults.Further research is required to determine the optimal treatment duration and strategies for managing therapy inter‑ ruptions. Advancements in molecular genetics and targeted therapies have revolutionized the management of histio‑ cytic neoplasms. However, ongoing research is crucial for optimizing patient outcomes.

Type 1 diabetes (T1D) is a chronic autoimmune disease characterized by the destruction of insulin-producing beta-cells in the pancreas.Genetic variations within the major histocompatibility complex (MHC) significantly influence the development of T1D, with diseaseprogression often indicated by the presence of autoantibodies. Until recently, insulin therapy was the sole treatment for T1D. However, in 2022, the Food and Drug Administration approved teplizumab, an anti-CD3 monoclonal antibody, as a novel immunomodulatory therapy to delay the onset of T1D. Various immunologic agents, including anti-CD antibodies and anti-cytokine autoantibodies, have been investigated across various stages of T1D in clinical trials. This article examines the current status of drug development for theprevention and treatment of T1D and summarizes key studies that aimed at delaying the onset of T1D using these agents. While effortsto halt or prevent the disease prior to clinical diagnosis have yielded limited success, post-diagnosis interventions have shown promising potential in slowing disease progression by preserving beta-cell function. Further investigation into long-term clinical outcomes related to the delay of T1D onset is necessary, and ongoing studies require extended follow-up to assess their full potential.

Type 1 diabetes (T1D) is a chronic autoimmune disease characterized by the destruction of insulin-producing beta-cells in the pancreas.Genetic variations within the major histocompatibility complex (MHC) significantly influence the development of T1D, with diseaseprogression often indicated by the presence of autoantibodies. Until recently, insulin therapy was the sole treatment for T1D. However, in 2022, the Food and Drug Administration approved teplizumab, an anti-CD3 monoclonal antibody, as a novel immunomodulatory therapy to delay the onset of T1D. Various immunologic agents, including anti-CD antibodies and anti-cytokine autoantibodies, have been investigated across various stages of T1D in clinical trials. This article examines the current status of drug development for theprevention and treatment of T1D and summarizes key studies that aimed at delaying the onset of T1D using these agents. While effortsto halt or prevent the disease prior to clinical diagnosis have yielded limited success, post-diagnosis interventions have shown promising potential in slowing disease progression by preserving beta-cell function. Further investigation into long-term clinical outcomes related to the delay of T1D onset is necessary, and ongoing studies require extended follow-up to assess their full potential.