Pathology findings in 2 patients who received CD19 CAR-T-cell therapy for CD19+MLL-rearranged B-ALL
| Day in relation to CAR-T-cell infusion . | Assay . | Tissue . | Result . |
|---|---|---|---|
| Case 1 | |||
| Pre-CAR-T cells | Flow cytometry | BMMC | Abnormal lymphoblasts expressing CD45, CD19, CD22, CD38, HLA-DR, CD15, CD33, CD13 (dim), and TdT (dim) |
| Karyotype | BMMC | 46,XX,t(4;11)(q21;q23),add(9)(p12)[cp20] | |
| FISH | BMMC | MLL rearranged | |
| IGH gene sequencing | BMMC | Index clone identified | |
| Day 22 after CAR-T cells | Flow cytometry | BMMC | No abnormal lymphoblasts |
| Karyotype | BMMC | 46,XX,t(4;11)(q21;q23),+6,add(9)(p13),-10/46,sl,del(1)(p34.1;q36.3),-6,+8[cp9]/80,slx2,-X,-1,-2,-4,-6,-6,-6,-11,-14,-15,-17,-18 | |
| FISH | BMMC | MLL rearranged | |
| IGH gene sequencing | BMMC | 19,507 copies of the index clone/1 × 106 BMMC | |
| Relapse | Flow cytometry | PBMC | Abnormal monocytic population expressing CD13 (dim), CD64, HLA-DR (dim), CD15, CD33, CD71, and MPO. No abnormal B cells. |
| FISH | PBMC | MLL rearranged | |
| IGH gene sequencing | PBMC | 70,789 copies of the index clone/1 × 106 PBMC | |
| Case 2 | |||
| Pre-CAR-T cells | Flow cytometry | BMMC | Abnormal lymphoblasts expressing CD19, CD38, CD58, CD22 (dim), HLA-DR, CD34, and CD45 |
| Karyotype | BMMC | 46,XX,ins(11;10)(q23;p12p1?1.2) | |
| FISH | BMMC | MLL rearranged | |
| IGH gene sequencing | BMMC | Index clone identified | |
| Day 21 after CAR-T cells | Flow cytometry | BMMC | No abnormal lymphoblasts |
| IGH gene sequencing | BMMC | Index clone not identified | |
| Relapse | Flow cytometry | BMMC | Abnormal myeloblasts expressing CD4, CD56, CD64, CD13, CD33, CD38, HLA-DR, CD34, CD45 and CD71. No abnormal B cell population. |
| Karyotype | BMMC | 46,XX,ins(11;10)(q23;p12p1?1.2) | |
| FISH | BMMC | MLL rearranged | |
| IGH gene sequencing | BMMC | Index clone not identified |
| Day in relation to CAR-T-cell infusion . | Assay . | Tissue . | Result . |
|---|---|---|---|
| Case 1 | |||
| Pre-CAR-T cells | Flow cytometry | BMMC | Abnormal lymphoblasts expressing CD45, CD19, CD22, CD38, HLA-DR, CD15, CD33, CD13 (dim), and TdT (dim) |
| Karyotype | BMMC | 46,XX,t(4;11)(q21;q23),add(9)(p12)[cp20] | |
| FISH | BMMC | MLL rearranged | |
| IGH gene sequencing | BMMC | Index clone identified | |
| Day 22 after CAR-T cells | Flow cytometry | BMMC | No abnormal lymphoblasts |
| Karyotype | BMMC | 46,XX,t(4;11)(q21;q23),+6,add(9)(p13),-10/46,sl,del(1)(p34.1;q36.3),-6,+8[cp9]/80,slx2,-X,-1,-2,-4,-6,-6,-6,-11,-14,-15,-17,-18 | |
| FISH | BMMC | MLL rearranged | |
| IGH gene sequencing | BMMC | 19,507 copies of the index clone/1 × 106 BMMC | |
| Relapse | Flow cytometry | PBMC | Abnormal monocytic population expressing CD13 (dim), CD64, HLA-DR (dim), CD15, CD33, CD71, and MPO. No abnormal B cells. |
| FISH | PBMC | MLL rearranged | |
| IGH gene sequencing | PBMC | 70,789 copies of the index clone/1 × 106 PBMC | |
| Case 2 | |||
| Pre-CAR-T cells | Flow cytometry | BMMC | Abnormal lymphoblasts expressing CD19, CD38, CD58, CD22 (dim), HLA-DR, CD34, and CD45 |
| Karyotype | BMMC | 46,XX,ins(11;10)(q23;p12p1?1.2) | |
| FISH | BMMC | MLL rearranged | |
| IGH gene sequencing | BMMC | Index clone identified | |
| Day 21 after CAR-T cells | Flow cytometry | BMMC | No abnormal lymphoblasts |
| IGH gene sequencing | BMMC | Index clone not identified | |
| Relapse | Flow cytometry | BMMC | Abnormal myeloblasts expressing CD4, CD56, CD64, CD13, CD33, CD38, HLA-DR, CD34, CD45 and CD71. No abnormal B cell population. |
| Karyotype | BMMC | 46,XX,ins(11;10)(q23;p12p1?1.2) | |
| FISH | BMMC | MLL rearranged | |
| IGH gene sequencing | BMMC | Index clone not identified |
BMMC, bone marrow mononuclear cells; PBMC, peripheral blood mononuclear cells.