Diagnostic signatures and immune cell infiltration characteristics in anti-GABABR encephalitis.

PURPOSE: Anti-gamma-aminobutyric acid B receptor (GABABR) encephalitis is an uncommon form of autoimmune encephalitis associated with a poor prognosis and a high fatality rate. We aim to find diagnostic markers for anti- GABABR encephalitis as well as the effects of immune cell infiltration on this pathology. METHODS: For quantitative proteomic analysis, isobaric tags for relative and absolute quantitation were used in conjunction with LC-MS/MS analysis. To conduct functional correlation analyses, differentially expressed proteins (DEPs) were identified. Following that, we used bioinformatics analysis to screen for and determine the diagnostic signatures of anti- GABABR encephalitis. ROC curves were used to evaluate the diagnostic values. To assess the inflammatory status of anti- GABABR encephalitis, we used cell-type identification by estimating relative subsets of the RNA transcript (CIBERSORT) and explored the link between diagnostic markers and infiltrating immune cells. RESULTS: Overall, 108 robust DEPs (47 upregulated and 61 downregulated) were identified, of which 11 were immune related. The most impressively enriched pathways were complemented and coagulation cascades, actin cytoskeleton regulation, and cholesterol metabolism; GSEA revealed that the enriched pathways were considerably differentially connected to immune modulation. Eleven immune-related DEPs were chosen for further investigation. We developed a novel diagnostic model based on CSF1R and AZGP1 serum levels using ROC analysis (area under the ROC curve = 1). M1 macrophages and activated natural killer cells are likely to play a role in course of anti- GABABR encephalitis. CONCLUSION: We identified CSF1R and AZGP1 are possible anti-GABABR encephalitis diagnostic indicators, and immune cell infiltration may have a significant impact on the development and occurrence of anti- GABABR encephalitis.

Factors associated with disease relapse rate in the Neuromyelitis optica spectrum disorder.

BACKGROUND AND OBJECTIVES: Neuromyelitis optica spectrum disorder (NMOSD) is a group of demyelinating diseases of the nervous system with high relapse rate and high disability rate without treatment, and we aimed to explore the influencing factors related to the recurrence of NMOSD and provide basis for clinical treatment in this study. METHODS: Referring to the diagnostic criteria for NMOSD issued in 2015, 259 patients were enrolled. Clinical information, cerebrospinal fluid (CSF) and serum analysis results, brain and spinal cord magnetic resonance imaging (MRI) findings, treatment details, and prognosis were all recorded. RESULTS: 176 (68.00%) participants were found to be AQP4 Ab-positive in serum or CSF, and the relapse rate was 36.67% (95/259). These 259 individuals were separated into two groups: non-release (n = 164) and relapse (n = 95). In terms of EDSS scores at onset, EDSS score after treatment, lesion location, serum creatinine (Cr) and treatment strategy, there were statistical differences between the two groups. Multivariable logistic regression analyses revealed five predictors for recurrence of NMOSD patients within two years: EDSS scores at onset, transverse myelitis, brain/brainstem, Cr, and Rituximab/immunosuppressants. CONCLUSION: It is essential to explore the risk factors related to recurrence and prevent them to reduce the risk of disability and improve the prognosis, and the recurrence rate of NMOSD may be affected by several factors.

Clinical features and outcomes of leucine-rich glioma-inactivated protein 1 and contactin protein-like 2 antibody-associated autoimmune encephalitis in a Chinese cohort.

The present study aimed to investigate the clinical manifestations, epidemiological characteristics, and outcomes of Chinese patients with voltage-gated potassium channel complex (VGKC) antibody-associated encephalitis. Patients diagnosed with VGKC antibody-associated encephalitis at our institution between January 2016 and December 2020 were included in this study. We retrospectively evaluated their clinical features, auxiliary examination results, treatments details, long-term outcomes, and risk factors for poor outcome. Of the 91 included patients, 61 (67.78%) were men and 30 (32.97%) were women. The most common clinical symptoms were seizures (n = 63, 69.23%), memory deficits (n = 62, 68.13%), mental behavioral disorders (n = 29, 31.87%), and hyponatremia (n = 57, 62.64%). Although patients with anti- leucine-rich glioma-inactivated 1 (LGI1) (n = 76) and anti- contactin-associated protein-like 2 (CASPR2) encephalitis (n = 15) had similar clinical manifestations, the former were more diverse. In total, 86 (94.51%) patients were treated with immunotherapy. Over a median follow-up period of 25 months, there were no mortalities and 14 (15.38%) patients experienced a relapse. Univariate analysis indicated differences in sex, modified Rankin Scale scores at onset, movement disorders, central hypoventilation, and intensive care unit occupancy between the good- and poor- outcome groups. Patients with anti-LGI1 and anti-CASPR2 encephalitis showed similar clinical manifestations while presenting delineating characteristics. Those with VGKC antibody-associated diseases generally responded well to immunotherapy and demonstrated favorable clinical outcomes. Several factors affected the prognosis, and a long-term follow-up examination is necessary.

Function of Delta4 gene and its effects on 32D cell differentiation.

BACKGROUND: Notch activation leads to transcriptional suppression of lineage-specific genes, inhibiting differentiation in response to inductive signals. The Notch signal system contains three parts: Notch molecules, Notch ligands and effectors. Delta4 is a newly-discovered Notch ligand which has received the attention of few detailed studies. This study sought to explore the biological function of Delta4 and observe its effects on 32D cell differentiation. METHODS: Delta4-expressing vector pTracer.CMV.Delta4.FLAG was constructed using molecular biological techniques. CHO cells stably transfected with pTracer.CMV.Delta4.FLAG were confirmed to have a Delta4 protein band via Western blotting. High-expression Delta4-CHO clones were selected for the following functional studies. Notch1-CHO and Notch2-CHO were used as host cells. After transiently transfecting with transition protein 1 (TP1), Delta4 activity was compared in both cell lines by means of luciferase analysis. CHO cells were incubated with Notch1-32D cells that had been transfected with Notch1 and were observed for granulocyte colony-stimulating factor (G-CSF)-induced differentiation. Jagged2-CHO and Delta4-CHO cells transfected with the Notch ligands Jagged2 and Delta4, respectively, were incubated with Notch1-32D cells to observed inhibition of Notch on G-CSF-induced differentiation. RESULTS: The vector pTracer.CMV.Delta4.FLAG was constructed successfully. CHO cells were stably transfected with the vector pTracer.CMV.Delta4.FLAG. Two CHO cell lines expressing Delta4 at high levels were selected for use in the study. Delta4 was found to induce signal activity via both Notch1 and Notch2 and the induction of signaling activity was stronger in Notch2 cells than in Notch1 cells. Compared with other Notch ligands, Delta4 was slightly weaker than Jagged2, but stronger than Delta1 and Jagged1 in terms of Notch1 ligands. In terms of Notch2, Delta4 had a strong signaling activity, but was weaker than Delta1, Jagged1, and Jagged2. Jagged2 could inhibit Notch1-32D cell differentiation induced by G-CSF, but Delta4 could not. CONCLUSIONS: Delta4 induces both Notch1 and Notch2 activity and is a ligand for both of them. The effect of Delta4 is stronger on Notch2 than that on Notch1. Jagged2 can inhibit Notch1-32D cell differentiation induced by G-CSF, but Delta4 cannot.