Integrated Analysis Identifies Upregulated SAMD9L as a Potential Biomarker Correlating with the Severity of Primary Sjögren's Syndrome

Multi-condition and multi-modal temporal profile inference during mouse embryonic development

The emergence of single-cell time-series datasets enables modeling of changes in various types of cellular profiles over time. However, due to the disruptive nature of single-cell measurements, it is impossible to capture the full temporal trajectory of a particular cell. Furthermore, single-cell profiles can be collected at mismatched time points across different conditions (e.g., sex, batch, disease) and data modalities (e.g., scRNA-seq, scATAC-seq), which makes modeling challenging. Here we propose a joint modeling framework, Sunbear, for integrating multi-condition and multi-modal single-cell profiles across time. Sunbear can be used to impute single-cell temporal profile changes, align multi-dataset and multi-modal profiles across time, and extrapolate single-cell profiles in a missing modality. We applied Sunbear to reveal sex-biased transcription during mouse embryonic development and predict dynamic relationships between epigenetic priming and transcription for cells in which multi-modal profiles are unavailable. Sunbear thus enables the projection of single-cell time-series snapshots to multi-modal and multi-condition views of cellular trajectories.

Role of chemokines CXCL9, CXCL10, CXCL11, and CXCR3 in the serum and minor salivary gland tissues of patients with Sjögren's syndrome

This study aimed to investigate the serum and expression levels of C-X-C motif chemokine ligand 9 (CXCL9), CXCL10, CXCL11, and CXC receptor 3 (CXCR3) in minor salivary glands (MSGs) of patients with primary Sjögren's syndrome (pSS), and to explore their correlations with clinical parameters. Serum samples from 49 patients diagnosed with pSS, 33 patients with rheumatoid arthritis (RA), and 30 healthy controls (HCs) were collected for measurements of CXCL9, CXCL10, CXCL11, and CXCR3. Additionally, CXCL levels in the MSG tissues were measured in 41 patients who underwent MSG biopsy. Correlations between CXCL and CXCL/CXCR levels in serum/MSG tissues and clinical factors/salivary scintigraphy parameters were analyzed. Serum CXCL11 and CXCR3 showed statistically significant differences among patients with pSS and RA and HCs (serum CXCL11, pSS:RA:HC = 235.6 ± 500.1 pg/mL:90.0 ± 200.3 pg/mL:45.9 ± 53.6 pg/mL; p = 0.041, serum CXCR3, pSS:RA:HC = 3.27 ± 1.32 ng/mL:3.29 ± 1.17 ng/mL:2.00 ± 1.12 ng/mL; p < 0.001). Serum CXCL10 showed a statistically significant difference between pSS (64.5 ± 54.2 pg/mL) and HCs (18.6 ± 18.1 pg/mL, p < 0.001), while serum CXCL9 did not exhibit a significant difference among the groups. Correlation analysis of clinical factors revealed that serum CXCL10 and CXCL11 levels positively correlated with erythrocyte sedimentation rate (r = 0.524, p < 0.001 and r = 0.707, p < 0.001, respectively), total protein (r = 0.375, p = 0.008 and r = 0.535, p < 0.001, respectively), globulin (r = 0.539, p < 0.001 and r = 0.639, p < 0.001, respectively), and European Alliance of Associations for Rheumatology SS Disease Activity Index (r = 0.305, p = 0.033 and r = 0.321, p = 0.025). Additionally, serum CXCL10 negatively correlated with the Schirmer test score (r = - 0.354, p = 0.05), while serum CXCL11 positively correlated with the biopsy focus score (r = 0.612, p = 0.02). In the MSG tissue, the percentage of infiltrating CXCL9-positive cells was highest (75.5%), followed by CXCL10 (29.1%) and CXCL11 (27.9%). In the correlation analysis, CXCL11-expressing cells were inversely related to the mean washout percentage on salivary gland scintigraphy (r =  - 0.448, p = 0.007). Our study highlights distinct serum and tissue chemokine patterns in pSS, emphasizing CXCL9's potential for early diagnosis. This suggests that CXCL10 and CXCL11 are indicators of disease progression, warranting further investigation into their roles in autoimmune disorders beyond pSS.