• All subjects or guardians must sign an informed consent form approved by the Ethics Committee in person before commencing any screening process;

• Age \> 18 years old, ≤ 70 years old, male or female;

• Diagnosis of relapsed/refractory (R/R) indolent B-cell lymphoma, and/or R/R diffuse large B-cell lymphoma (DLBCL). Refractory diseases are defined as one of the following：

‣ Patients with relapsed or refractory B-cell lymphoma treated with one standard treatment regimen and one salvage regimen treated with rituximab or another CD20 antibody drug and at least two treatment regiments appropriate for their disease, one of which should include anthracyclines;

⁃ After treatment with these regimens, patients maintain SD (SD duration ≤ 12 months) or still progress；

⁃ Recurrence after autologous hematopoietic stem cell transplantation, or recurrence of allogeneic HSCT, or inability to accept HSCT for various reasons；

⁃ Patients with double-strike or triple-strike B-cell lymphoma who did not respond to second-line therapy；

• CD19 expression was positive by immunohistochemistry or flow cytometry (accept the results of this peripheral blood mononuclear cells or previous report from a Class A tertiary hospital before peripheral blood collection);

• If the subject has progressed or relapsed after prior CD19 CAR-T cell therapy, the planned apheresis phase should be at least 1 month after that, or the subject has been treated with other biologics, but is in the washout period;

• At least one measurable lesion at baseline, according to the Preliminary Assessment, staging and Response Assessment recommendations for Hodgkin's and non-Hodgkin's lymphoma (2014 edition);

• Expected survival time greater than 12 weeks;

• ECOG score 0-1 (subjects with central nervous system diseases caused by leukemia or lymphoma need to be determined by the investigator);

• Organ function：

‣ Complete blood count (CBC) test \[the following criteria should be met within 24 hours prior to apheresis, and supportive treatment such as transfusion, platelet transfusion, cell growth factor (except recombinant erythropoietin) should be avoided within 7 days prior to detection\]

• Lymphocyte count ≥ 0.5×109/L (except for those receiving bridging chemotherapy);

∙ Platelet count ≥ 25×109/L;

∙ Hemoglobin ≥ 70.0 g/L

⁃ Blood Biochemistry:

• Serum creatinine (Scr) ≤ 1.5 x ULN, or

∙ endogenous creatinine clearance ≥ 40 mL/min (using Cockcroft-Gault formula);

∙ alanine aminotransferase (ALT) ≤ 2.5 x ULN;

∙ aspartate aminotransferase (AST) ≤ 2.5 ×ULN;

∙ Total bilirubin (TBIL) ≤ 2 ×ULN; Subjects with total bilirubin \< 3 × ULN and direct bilirubin \< 1.5× ULN with Gilbert-.Meulengracht syndrome could be included;

∙ Serum lipase and amylase ≤ 1.5×ULN;

∙ Alkaline phosphatase (ALP) ≤ 2.5 ×ULN;

∙ In case of bone or liver metastasis, AST, ALT and ALP ≤ 5 ×ULN;

∙ Prothrombin time (PT) extended ≤ 4 s, fibrinogen ≥ 1 g/L, activated partial thromboplastin time (APTT) ≤ 1.5 ×ULN;

⁃ Pulmonary function: ≤CTCAE grade 1 dyspnea and oxygen saturation of blood (SaO2) \> 91% in indoor air environment..

• Hemodynamic stability was determined by echocardiography or multichannel radionuclide angiography (MUGA) and LVEF ≥45％;

• Patients using the following drugs must meet the following conditions:

‣ Steroid: Therapeutic doses of steroids must be discontinued 2 weeks prior to Meta10-19 infusion. However, physiological replacement doses of steroids are permitted, hydrocortisone or its equivalent \< 6-12mg/mm2/ day；

⁃ Immunosuppressive agent: Any immunosuppressive drug must be stopped ≥4 weeks before the informed consent is signed;

⁃ Stop all anti-proliferation therapies other than preconditioning chemotherapy in the 2 weeks before Meta10-19 infusion；

⁃ Treatment for CNS disease must be stopped 1 week before Meta10-19 infusion (e.g., intrathecal methotrexate)

• The patient has recovered from the toxicity of the previous treatment, that is, the CTCAE toxicity grade is less than 1 (The exception is specific toxicity of grade 2 or less, such as hair loss, which the researchers have determined is not recoverable in a short period of time) is suitable for pretreatment chemotherapy and CAR-T cell therapy;

• Women of childbearing age and all male patients must consent to use a effective contraception for at least 12 months after Meta10-19 infusion and until two consecutive PCR tests show no more CAR T cells in vivo.