Umbilical cord blood mononuclear cells(Beijing Gaobo Boren Hospital)

This is a single-center, open-label, non-randomized, single-arm clinical trial. Patients with refractory lupus neritis (SLE-LN), systemic sclerosis (SSc), and primary Sjogren syndrome combined with pulmonary artery hypertension (pSS-PAH receive umbilical cord blood CD19-BCMA CAR T cell therapy. The primary objective is to prospectively assess the safety of umbilical cord blood CD19BCMA CAR T cell therapy in patients with refractory lupus nephritis (SLE-LN), systemic sclerosis (SSc), and primaryjogren syndrome combined with pulmonary artery hypertension. The primary endpoint is the type and incidence of dose-limiting toxicity (DLT) within 28 days after theusion of umbilical cord blood CD19-BCMA CAR T cells. It is anticipated that 45-54 participants will be recruited.