Preclinical Testing of Viral Therapeutic Efficacy in Pristane-Induced Lupus Nephritis and Diffuse Alveolar Hemorrhage Mouse Models

Animal models of neuropsychiatric systemic lupus erythematosus: deciphering the complexity and guiding therapeutic development

Systemic lupus erythematosus (SLE) poses formidable challenges due to its multifaceted etiology while impacting multiple tissues and organs and displaying diverse clinical manifestations. Genetic and environmental factors contribute to SLE complexity, with relatively limited approved therapeutic options. Murine models offer insights into SLE pathogenesis but do not always replicate the nuances of human disease. This review critically evaluates spontaneous and induced animal models, emphasizing their validity and relevance to neuropsychiatric SLE (NPSLE). While these models undoubtedly contribute to understanding disease pathophysiology, discrepancies persist in mimicking some NPSLE intricacies. The lack of literature addressing this issue impedes therapeutic progress. We underscore the urgent need for refining models that truly reflect NPSLE complexities to enhance translational fidelity. We encourage a comprehensive, creative translational approach for targeted SLE interventions, balancing scientific progress with ethical considerations to eventually improve the management of NPSLE patients. A thorough grasp of these issues informs researchers in designing experiments, interpreting results, and exploring alternatives to advance NPSLE research.

Exosomes Derived from Human Umbilical Cord Mesenchymal Stem Cells Alleviate Diffuse Alveolar Hemorrhage Associated with Systemic Lupus Erythematosus in Mice by Promoting M2 Macrophage Polarization via the microRNA-146a-5p/NOTCH1 Axis

Systemic lupus erythematosus (SLE)-associated diffuse alveolar hemorrhage (DAH) is a rare but extremely harmful condition. The current study sought to dissect the mechanisms underlying the effects of human umbilical cord mesenchymal stem cell (HUCMSC)-derived exosomes on M2 macrophage polarization in SLE-associated DAH via the microRNA (miR)-146a-5p/NOTCH1 axis. A DAH mouse model was established using pristane. Exosomes were isolated from HUCMSCs transfected or untransfected with the miR-146a-5p antagonist or agonist and their NCs and then injected into DAH mice. Additionally, miR-146a-5p was overexpressed in macrophages. Expression of miR-146a-5p, NOTCH1, M1 macrophage markers, and M2 macrophage markers was measured in mice and macrophages, and inflammatory factor levels were detected. Mouse lung injuries were evaluated, so was the binding of miR-146a-5p to NOTCH1. Rescue experiments were conducted in mice and macrophages using NOTCH1 shRNA and pcDNA3.1-NOTCH1, respectively. NOTCH1 expression was enhanced in DAH mice. HUCMSC-derived exosomes reduced NOTCH1 expression, bleeding, inflammation, and M1 macrophage polarization but elevated M2 macrophage polarization in lung tissues of DAH mice. Mechanistically, NOTCH1 is negatively targeted by miR-146a-5p. miR-146a-5p overexpression diminished M1 marker and inflammatory factor levels but enhanced M2 marker levels in macrophages, which was nullified by NOTCH1 overexpression. HUCMSC-derived exosomes with miR-146a-5p inhibition increased NOTCH1 expression, worsened bleeding and inflammation, and augmented M1 macrophage polarization while decreasing M2 macrophage polarization in lung tissues of DAH mice, which was abrogated by silencing NOTCH1. HUCMSC-derived exosomes diminished NOTCH1 expression to accelerate M2 macrophage polarization via delivery of miR-146a-5p, thus alleviating SLE-associated DAH in mice.

Therapeutic potential of galectin-1 and galectin-3 in autoimmune diseases

Galectins are a highly conserved protein family that binds to β-galactosides. Different members of this family play a variety of biological functions in physiological and pathological processes such as angiogenesis, regulation of immune cell activity, and cell adhesion. Galectins are widely distributed and play a vital role both inside and outside cells. It can regulate homeostasis and immune function in vivo through mechanisms such as apoptosis. Recent studies indicate that galectins exhibit pleiotropic roles in inflammation. Furthermore, emerging studies have found that galectins are involved in the occurrence and development of autoimmune diseases such as systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), type 1 diabetes (T1D) and systemic sclerosis (SSc) by regulating cell adhesion, apoptosis, and other mechanisms. This review will briefly discuss the biological characteristics of the two most widely expressed and extensively explored members of the galectin family, galectin-1 and galectin-3, as well as their pathogenetic and therapeutic roles in autoimmune diseases. These information may provide a novel and promising therapeutic target for autoimmune diseases.