The primary objective was to evaluate the safety of CD7 CAR-T cells for the treatment of subjects with relapsed/refractory AID. CD7 CAR-T cells were infused in a single infusion in subjects who were screened after signing an informed consent form and undergoing single nucleus cell collection and pretreatment, and blood was collected before and after the infusion for pharmacokinetic, pharmacodynamic, immunogenicity, and safety evaluations.

Subjects who meet the inclusion/exclusion criteria will be entered into 3 groups in sequential order for a single dose. The dose-escalation study utilizes a "3+3" design, i.e., 3-6 subjects in each group will complete a single dose.

After the last subject in each dose group completes a dose-limiting toxicity (DLT) assessment window of 28 days after the single dose, enrollment in the next dose group can begin.

When 1 DLT occurs in 3 subjects in a dose group, 3 additional subjects are required in the same dose group (up to 6 subjects in that dose group have completed DLT assessment): if no DLT occurs in the 3 additional subjects, continue the dose escalation; if 1 of the 3 additional subjects develops a DLT, stop the dose escalation; if >1 of the 3 additional subjects DLT occurs, the dose escalation is stopped and a one-dose reduction is required to continue enrolling 3 more subjects for DLT assessment.

Inclusion Criteria:

- Diagnosed relapsing/refractory systemic sclerosis that has failed treatment with at least two immunosuppressive and/or biologic agents.

Bone marrow and coagulation function, liver and kidney function, cardiopulmonary function are satisfied No serious mental disorders

Exclusion Criteria:

- Malignancy other than AID disease within 5 years prior to screening Hepatitis B surface antigen (HBsAg) positive, AIDS, syphilis and other virus positive persons Severe heart disease

Research details