Clinical Significance of OX40 and OX40 Ligand in the Peripheral Blood of Patients with Myasthenia Gravis

Relative change rate of anti-acetylcholine receptor antibodies concentration Correlates with the recurrence of myasthenia gravis in AChR-Abs-positive patients

BACKGROUNDS

Myasthenia gravis (MG) is an autoimmune disease predominantly caused by anti-acetylcholine receptor antibodies (AChR-Abs). In this study, the relationship between MG relapse and AChR-Abs concentration were investigated.

METHODS

We retrospectively reviewed the clinical records of 41 patients with AChR-Abs-positive MG. Data collected included age, sex, MG status within 12 months (untreated status, UTMG; recurrence status, RCMG), MG subgroups, QMGs, AChR-Abs concentration and treatments. The relative change rate (RCR) of AChR-Abs concentration was calculated as: RCR(%)=(AChR-Abs-AChR-AbsUTMG)/AChR-AbsUTMG/month*100. ROC curve analysis and binary logistic regression analyses were used to evaluate the association between these factors and MG recurrence.

RESULTS

Within 12 months, 12 patients experienced a recurrence (RCMG). A weak correlation was observed between AChR-Abs level in UTMG and QMGs (r = 0.336, p = 0.032). MG subgroups, QMGs, AChR-Ab levels and RCR differed significantly between RCMG and non-RCMG group. Single factor ROC curves indicated that AChR-Abs concentration, RCR and MG subgroups were related to MG recurrence (AUC = 0.724, 0.736, 0.736). Combining with RCR and MG subgroups, the ROC yielded an AUC of 0.899, demonstrating high sensitivity and specificity.

CONCLUSION

RCR of AChR-Abs was correlated with MG progression, and repeated AChR-Abs measurements can assist in monitoring disease status and guiding therapeutic decision-making.

Macrophage migration inhibitory factor: A noval biomarker upregulates in myasthenia gravis and correlates with disease severity and relapse

OBJECTIVE

To explore the relationship between macrophage migration inhibitory factor (MIF) and disease severity and relapse in patients with myasthenia gravis (MG).

METHODS

145 MG patients including 79 new-onset patients, 30 remission patients and 36 relapse patients were enrolled in this study. The detailed characteristics of all enrolled MG patients were routinely recorded, including gender, age, type, MGFA classification, antibody, thymic status, clinical score, treatment, MGFA-PIS and B cell subsets (memory B cells, plasmablast cells and plasma cells) detected by flow cytometry. Serum MIF levels were measured by enzyme-linked immunosorbent assay (ELISA) kit. The correlation of MIF levels with clinical subtypes, disease severity and B cell subsets were investigated. Moreover, logistic regression analysis was applied to assess the factors affecting relapse of generalized MG (GMG).

RESULTS

Serum MIF levels were higher in new-onset MG patients than those in controls and were positively associated with QMG score, MGFA classification and memory B cells. Subgroup analysis revealed that MIF levels were increased in GMG patients than in ocular MG (OMG), as well as elevated in MGFA III/IV compared with MGFA I/II. With the remission of the disease, the expression of serum MIF decreased. The multivariate logistic regression models indicated that high MIF and thymoma was a risk factor for relapse of GMG, and rituximab could prevent disease relapse.

CONCLUSIONS

MIF can be used as a novel biomarker to reflect disease severity and predict disease relapse in MG patients.

Differential expression of immune checkpoints (OX40/OX40L and PD-1/PD-L1) in decidua of unexplained recurrent spontaneous abortion women

In this study, we aimed to investigate the expression of OX40, OX40L, PD-1 and PD-L1 in patients with unexplained recurrent spontaneous abortion (URSA) compared to normal pregnancies (NP). A total of 50 patients who were diagnosed with URSA and 41 NP were recruited to this study. Real-time polymerase chain reaction (RT-PCR) was used to determine the expression of OX40, OX40L, PD-1 and PD-L1 in decidual tissues; Immunohistochemistry (IHC) was conducted to characterize the distribution of the involved genes in decidual tissues; Double immunofluorescence staining was used to prove the localization of the involved genes in decidual tissues. The concentrations of OX40L and PD-L1 in plasma were measured with enzyme-linked immunosorbent assay (ELISA). The expression of OX40L in the decidua of URSA patients was significantly increased compared to that in the NP group, while the expression of PD-L1 in the URSA group was decreased compared to that in the NP group. Both proteins are localized in the decidual stroma as analyzed by double immunofluorescence staining. The staining results were confirmed at the mRNA level of decidual tissues, while the mRNA level of peripheral blood showed no significant difference. In conclusion, the results suggest that decidual stromal cells may promote the interaction with OX40 on T cells by upregulating the expression of OX40L and reduce the interaction with PD-1 on T cells by downregulating the expression of PD-L1 in URSA patients, which may interfere with the immune tolerance of the maternal-fetal interface, leading to poor pregnancy outcomes.