• Age 18-70 (inclusive).

• Subjects who meet the following requirements:

‣ 1 Histologically confirmed refractory/relapsed B cell NHL, including the following types defined by WHO 2016:

⁃ Diffuse large B-cell lymphoma not otherwise specified (DLBCL-NOS);

⁃ Primary mediastinal (thymic) large B-cell lymphoma (PMBCL);

⁃ Transformed follicular lymphoma (TFL);

⁃ High-grade B-cell lymphoma with MYC and BCL2 and/or BCL6 rearrangements (HGBCL);

⁃ Follicular lymphoma (FL);

⁃ Mantle cell lymphoma (MCL) (pathologically confirmed, with documentation of monoclonal B cells that have a chromosome translocation t(11;14)(q13;q32) and/or overexpress cyclin D1);

⁃ Marginal zone lymphoma (MZL), including nodal or splenic marginal zone B-cell lymphoma and mucosa-associated lymphoid tissue (MALT) lymphoma.

‣ 2 Relapsed disease is defined as disease progression (PD) after achieving disease remission (including CR and PR) with the latest standard regimen.

‣ 3 Refractory disease is defined as no CR to first-line therapy:

⁃ Evaluation of PD (never reached response or SD) after standard first-line treatment, or

⁃ SD as best response after at least 4 cycles of first-line therapy (eg,4 cycles of R-CHOP), or

⁃ PR as best response after at least 6 cycles and biopsy-proven residual disease or disease progression ≤ 6 months of therapy, or

⁃ Refractory post-autologous stem cell transplant (ASCT): i. Disease progression or relapsed less than or equal to 12 months of ASCT (must have biopsy proven recurrence in relapsed individuals); ii. If salvage therapy is given post-ASCT, the individual must have had no response to or relapsed after the last line of therapy.

‣ 4 Individuals who are intolerant to standard treatment can also be included in the study in the investigator's judgment.

• Individuals must have received adequate prior therapy:

‣ 1 For MCL, prior therapy must have included:

⁃ Anthracycline or bendamustine-containing chemotherapy and

⁃ Anti-CD20 monoclonal antibody (unless investigator determines that tumor is CD20-negative) and

⁃ Bruton's tyrosine kinase inhibitor (BTKi).

‣ 2 For other types, prior therapy must have included:

⁃ Anti-CD20 monoclonal antibody (unless investigator determines that tumor is CD20-negative) and

⁃ Anthracycline containing chemotherapy regimen.

‣ 3 For individual with transformed FL must have relapse or refractory disease after transformation to DLBCL.

• At least 1 measurable lesion: lymph node site with a long axis \>1.5cm, extranodal site with a long axis \>1.0cm (according to the Lugano2014 criteria). Lesions that have been previously irradiated will be considered measurable only if progression has been documented following completion of radiation therapy.

• CD19 positive (detected by immunohistochemistry \[IHC\]).

• Toxicities due to prior therapy must be stable and recovered to ≤ Grade 1 (except for hematological toxicities and clinically non-significant toxicities such as alopecia).

• Eastern Cooperative Oncology Group (ECOG) performance status ≤ 2.

• Absolute neutrophil count (ANC) ≥ 1 x 10\^9/L, Platelet count ≥50 x 10\^9/L, hemoglobin (Hgb) ≥ 80g/L (hemocytopenia caused by lymphoma invasion of bone marrow is not subject to conditions above).

• Adequate renal, hepatic, pulmonary and cardiac function defined as:

‣ 1 Serum creatinine≤1.5 upper limit of normal (ULN) or creatinine clearance (as estimated by Cockcroft Gault) ≥ 60 mL/min.

‣ 2 Serum alanine aminotransferase / aspartate aminotransferase (ALT/AST) ≤ 3 upper limit of normal (ULN); Total bilirubin ≤ 1.5 ULN, except in subjects with 3) Gilbert's syndrome.

‣ 3 Cardiac ejection fraction ≥ 50%, no evidence of pericardial effusion as determined by an echocardiogram (ECHO), and no clinically significant electrocardiogram (ECG) findings.

‣ 4 Coagulation Function: International Normalized Ratio (INR) ≤ 1.5 times the upper limit of normal (ULN), and Activated Partial Thromboplastin Time (APTT) ≤ 1.5 times ULN.

‣ 5 Baseline oxygen saturation \>91% on room air.

⁃ Subjects of both genders who are willing to practice birth control from the time of consent through 6 months after the completion of conditioning chemotherapy. Females of childbearing potential must have a negative serum or urine pregnancy test (females who have undergone surgical sterilization or who have been postmenopausal for at least 2 years are not considered to be of childbearing potential).

⁃ Voluntarily participate in this clinical trial and sign an informed consent form.