Autoimmune diseases result from dysregulated immune responses, primarily driven by CD4+ T cell imbalances, leading to chronic inflammation and tissue destruction. Conventional cytokine-based therapies, including IL-2 for regulatory T cell (Treg) expansion and IL-6 or IL-17 inhibition for inflammation suppression, have shown promise in modulating immune responses. However, challenges such as systemic toxicity, short half-life, and off-target effects limit their therapeutic efficacy. Lipid nanoparticles (LNPs) have emerged as a next-generation drug delivery platform, offering enhanced cytokine stability, targeted cellular uptake, and controlled release, thereby overcoming limitations associated with free cytokine administration. Preclinical studies have demonstrated that LNP-IL-2 selectively expands Tregs in type 1 diabetes models, while IL-10-loaded LNPs suppress synovial inflammation in rheumatoid arthritis more effectively than conventional cytokine therapies. Optimization of ligand density and affinity on LNP surfaces is emerging as a key determinant of CD4T cell targeting efficiency. Additionally, LNP-encapsulated siRNA targeting IL-6 and IL-23 has shown superior suppression of inflammatory pathways in lupus and psoriasis. These findings underscore the potential of LNP-mediated cytokine delivery to precisely modulate CD4+ T cell function, restoring immune homeostasis in autoimmune diseases. Despite promising preclinical and early clinical data, challenges remain, including optimizing biodistribution, ensuring selective T cell targeting, and mitigating immune activation risks. This review provides an in-depth analysis of CD4+ T cell subsets in autoimmunity, the advantages of LNP-based cytokine therapies, and their translational potential. The integration of LNP technology into cytokine immunotherapy offers a novel, minimally toxic, and durable approach to reprogramming immune responses, paving the way for precision medicine in autoimmune disease management. SIGNIFICANCE: Autoimmune disorders are characterized by chronic inflammation driven by dysregulated cytokine activity. Traditional cytokine therapies often suffer from systemic toxicity and limited targeting precision. This manuscript highlights recent advancements in lipid nanoparticle (LNP) technology for the targeted delivery of cytokines, offering enhanced therapeutic efficacy and safety. By enabling precise modulation of immune responses at disease sites, LNP-based delivery systems represent a transformative approach in immunotherapy. This review underscores the potential of LNPs to overcome current limitations in autoimmune treatment, paving the way for next-generation precision medicine strategies. +
