Clinical Study of Targeting CD7 CAR-T Cells in the Treatment of Autoimmune Diseases

Inclusion Criteria: 1. Diagnosed as refractory Crohn disease, ulcerative colitis (collectively called Crohn's disease), and the conventional hormone therapy is not effective and (or) there is no effective treatment: 1. At least 6 months before screening, diagnosed as Crohn's disease based on typical radiological results and/or typical histology. 2. In addition to corticosteroids, after the use of immunosuppressive agents (usually azathioprine, methotrexate, and two biological agents (usually infliximab, adalimumab and/or setolizumab), the course of the disease is still Unsatisfactory. Patients should still have relapsed and refractory diseases after glucocorticoid and/or immunosuppressive treatment, or clearly show intolerance/toxicity to these drugs 2. Diagnosed as refractory dermatomyositis, and conventional hormone therapy is not effective and (or) ineffective treatment methods: 1. At least 6 months before screening, confirmed or possible dermatomyositis according to Bohan and Peter criteria; 2. At least it has no response to prednisone and other first-line immunosuppressants (such as methotrexate, mycophenolate mofetil, or azathioprine), or has obvious toxicity or intolerance to these therapies. 3. Refractory adult STILL disease 1. Conform the diagnostic criteria for adult STILL disease (according to Yamaguchi et al., J. Rheumatology, 1992); 2. After receiving non-steroidal anti-inflammatory drugs, glucocorticoids, anti-rheumatic drugs (DMARDs) and other treatments, there are still relapsed and refractory diseases, or clearly show that these drugs are intolerant/toxic. 4. Rheumatoid arthritis 1. Conform the diagnostic criteria for rheumatoid arthritis in 2010 ACR classification criteria; 2. Have received DMARDs or glucocorticoid therapy, but failed to achieve clinical remission, or clearly showed intolerance/toxicity to these drugs. The following screening can be performed by meeting any of the above 4 entry criteria 5. Estimated survival time\> 12 weeks; 6. Patients had a negative urine pregnancy test before the start of administration and agreed to take effective contraceptive measures during the test period until the last follow-up; 7. Patients or their legal guardians volunteer to participate in the study and sign the informed consent. Exclusion Criteria: * Subjects with any of the following exclusion criteria were not eligible for this trial: 1. History of craniocerebral trauma, conscious disturbance, epilepsy, cerebrovascular ischemia, and cerebrovascular, hemorrhagic diseases; 2. Electrocardiogram shows prolonged QT interval, severe heart diseases such as severe arrhythmia in the past; 3. Pregnant (or lactating) women; 4. Patients with severe active infections (excluding simple urinary tract infection and bacterial pharyngitis); 5. Active infection of hepatitis B virus or hepatitis C virus; 6. Systemic steroids have used in the 4 weeks before participating in the treatment (except recently or currently using inhaled steroids); 7. Those who have used any gene therapy products before. 8. The proiferation rate is less than 5 times response to CD3/CD28 co-stimulation signal; 9. Serum creatinine \> 2.5mg/dl or ALT / AST \> 3 times ULN or bilirubin \> 2.0mg/dl; 10. Those who suffer from other uncontrolled diseases are not suitable to join the study; 11. HIV infection; 12. Any situation that the researchers believe may increase the risk of patients or interfere with the test results.