The investigators will recruit active ankylosing spondylitis patients for injection treatment of Human Mesenchymal Stem Cells (a prospective, open-label, masculine medicine controlled(NSAIDs), clinical trial), and collect their Peripheral Blood Lymphocyte (PBMCs) and sera before and after the treatment of 24 weeks to test the gene expression profiles and study related pathogenesis of AS

Inclusion Criteria:

1. Aged from 16-65 years, sign the Informed Consent
2. Fulfill 1984 modified NewYork classification criteria for AS
3. Have an active refractory disease defined by a score ≥40 on the Bath AS Disease Activity Index (BASDAI) (0-100) despite optimal non-steroidal anti-inflammatory drug (NSAID) treatment.
4. Commitment to contraceptive for woman

Exclusion Criteria:

1. Completely stiff spine
2. Received spinal or joint surgery within 2 months
3. Received anti-TNF therapy within 3 months
4. History of the listed diseases: heart failure, Multiple sclerosis, severe chronic obstructive pulmonary disease, frequent infections, lymphoma or other cancers, tuberculosis
5. Female of pregnancy or breast feeding
6. Hb≤ 9g/dl for male or Hb ≤ 8.5 g/dl for male, ALT/AST≥2folds of upper level normal range, Creatine≥120mol/L(≤1.4mg/dl)