The goal of this study is to conduct a prospective, double-blind, randomized placebo-controlled clinical trial to investigate the safety and efficacy of mesenchymal stem cells treatment for AIDS patients at late stage.

Mesenchymal stem cells (MSCs) possess immunomodulatory, anti-inflammatory, and regenerative properties. The safety and effectiveness of MSCs have been investigated in various clinical trials for the treatment of several disorders, including graft-versushost disease, inflammatory bowel disease, and multiple sclerosis. It has been reported that MSC treatment in HIV-infected patients with immunological nonresponders resulted in a significant increase in circulating CD4+ T lymphocytes and a decrease of the activation of T lymphocytes and soluble inflammation mediator levels without significant adverse effects or loss of viremia control. However, the therapeutic efficacy of MSC treatment for AIDS patients at late stage is not well-understood. This study aims to investigate the safety and efficacy of MSC treatment for AIDS patients at late stage.

Inclusion Criteria:

1. Confirmed HIV infection, aged 18-65, both genders
2. CD4+T count less than 500 cells/ul at baseline.
3. No serious AIDS related events. 3. could understand and sign the informed consent form and comply with the requirements of this study.

4. agree not to participate in other studies and not to receive other immunotherapies during the period of participation in this study

Exclusion Criteria:

1. have HBV/HCV/HDV/HEV infection, and the virological test is positive.
2. The viral load for CMV and EBV is more than 1000 copies/ML.
3. have HIV-2 infection.
4. have serious complications in organs including renal, circulatory, respiratory, digestive, endocrine, neural and immunological diseases and tumors.
5. received treatment of hormones or other immunosuppressive drugs for a long time.
6. with serious AIDS related or unrelated events.
7. received immunosuppressive drugs or systemic cytotoxic drugs for more than 3 months before recruiting
8. have poor compliance during treatment.
9. drug addiction within 6 months, or the urine drug test is positive
10. participate in other clinical trials currently
11. pregnant, breastfeeding, or have fertility requirements.
12. unable or unwilling to provide informed consents, or unable to comply with research requirements.
13. Other serious situations that may hinder clinical trials.