Immune infiltration analysis reveals immune cell signatures in human and mouse model of primary Sjögren's syndrome in salivary gland tissue

Background: The mouse model is the basis for primary Sjögren's syndrome research, but the depth of comparison between mice and humans in salivary gland immune cells is limited. Methods: : Firstly, the gene expression profile of salivary glands of normal human and pSS patients was downloaded from the Gene Expression Omnibus database. The proportion of infiltrating immune cell subsets was then assessed by cell type identification by estimating relative subsets of RNA transcripts (CIBERSORT). The experimental Sjögren's syndrome (ESS) model mice was successfully constructed using the salivary gland (SG) protein of the salivary gland, and the successful mice were screened by measuring the amount of saliva and histopathological score. Based on mouse salivary gland tissue RNA-Seq data, the seq-ImmuCC model was used to quantitatively analyze the composition ratio of 10 immune cells in salivary gland tissue from patients with primary Sjögren's syndrome and mouse models. Results: : In the study, 31 human data samples were calculated and finally obtained by the CIBERSORT deconvolution method. The results of immune cell infiltration found that compared with normal human salivary gland tissue, gamma delta T cells were significantly different from naive CD4 + T cells content was significantly increased, while plasma cell content decreased. Principal component analysis (PCA) results suggested differences in immune cell infiltration between pSS patients and normal subjects. At the same time, The ESS model mice was constructed. For the mouse data analysis, we found that the proportion of macrophages increased, while the proportion of CD4 + T cells, B cells and monocytes decreased. After comprehensive analysis, we found that pSS patients and models were smaller the proportion of monocytes in salivary gland tissue of mice decreased, while the proportion of macrophages increased. The infiltration proportions of CD4 + T cells, CD8 + T cells and B cells showed a certain difference. Conclusions: : Through a comprehensive analysis of salivary gland immune infiltration in patients with primary Sjögren's syndrome and model mice, we demonstrate conservation and nonconservation in the mouse and human immune systems at the level of immune cells, helping to explain the primary Regulation of immune mechanisms during the development of Sjögren's syndrome.