The effect of Telitacicept treatment on the changes of transitional regulatory B lymphocyte T1, T2B cell subsets and plasma blasts and the expression levels of cytokines IL-10, IL-35, April and BAFF in SLE.

Inclusion Criteria:

1. The diagnosis meets the 2019 EULAR/ACR classification criteria for SLE;
2. Age 18-70 years old;
3. To be on a stable SLE regimen, participants were required to receive standard treatment at least 1 month prior to treatment with a biologic (Telitacicept);
4. Lupus activity Index score (SELENA-SLEDAI) ≥ 8 at screening;
5. Positive anti-nuclear antibody or anti-DSDNA antibody;
6. Combined antiphospholipid syndrome should meet the diagnostic criteria: that is, meet one clinical criterion and one laboratory criterion.

Exclusion Criteria:

1. Active infections (such as shingles, HIV infection, active tuberculosis, etc.) during the screening period;
2. Central nervous system disease (including epilepsy, psychosis, organic encephalopathy syndrome, cerebrovascular accident, encephalitis, central nervous system vasculitis) caused by SLE or not caused by SLE in the last 2 months;
3. Have active hepatitis or a history of severe liver disease;
4. Patients with immune deficiency, uncontrolled severe infection, and active or recurrent digestive ulcer;
5. Pregnant women, breastfeeding women and men or women who have planned to have a baby in the last 12 months;
6. Allergic reaction: history of allergic reaction to human biological products;
7. Those who received live vaccine within the last month;
8. Participants who have participated in any clinical trial within 28 days prior to initial screening/or 5 times the half-life of the study compound (taking an older time);
9. B cell targeted therapy, such as rituximab or epazumab, within one year;
10. Use tumor necrosis factor inhibitors and interleukin-receptor blockers within one year;
11. Patients receiving intravenous gamma globulin (IVIG), prednisone ≥ 100 mg/d for more than 14 days within one month or undergoing plasmapheresis;
12. Psychopaths with depression or suicidal thoughts.

Patients with systemic lupus erythematosus meeting inclusion criteria