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A. Laghmouchi et al.
Table 2. Cell-lineage recognition patterns of HLA-class II-restricted T-cell clones provoked by HLA-class II mismatched dendritic cells.
Response
1.
2. 3. 4. 5. a
DC: CD14-derived dendritic cells, EBV-LCL: Epstein-Barr virus-transformed lymphoblastoid cell lines, HeLa: cervical cancer cell line, Fibro: skin-derived human fibroblasts. The number of T-cell clones with the respective cell-lineage-restriction pattern are indicated for each response.
Allo HLA-class II restriction
DPB1*04:01:01
Total tested T-cell clones
16
Cell-lineage recognition patterns:
DC & EBV-LCL
10
DC DC, EBV-LCL, HeLa and
Fibro
- 6
DC, EBV-LCL, and Fibro
-
DC, EBV-LCL, and HeLa
-
DPB1*04:02 30 10 9 11 - - DPB1*02:01:02 423 219 14 83 95 22 DPB1*03:01:01 546 36 29 435 43 3
DPB1*04:01
5.b DQB1*06:03 65 37 9 6 10 3
89 30 15 38 2 4
sentative HLA-DQB1*06:03-restricted T-cell clones shown in Online Supplementary Figure S5). These results illustrate that the allo-HLA-DP and allo-HLA-DQ T-cell repertoire provoked by stimulation of donor T cells with HLA-class II-mismatched DC contains T-cell clones that show HLA- DP- or HLA-DQ-restricted recognition of DC, but not of EBV-LCL expressing the targeted mismatched HLA-DP or HLA-DQ allele.
The allo-HLA-DP-specific T-cell repertoire comprises
T cells with different cell-lineage-restricted recognition patterns
To further investigate the presence of T cells with a cell-lineage-specific recognition pattern within the allo- HLA-DP- and allo-HLA-DQ-specific T-cell repertoires, the reactivity pattern of the majority of allo-HLA-DP- and allo-HLA-DQ-restricted T-cell clones (n=1104, some T-cell clones were discarded because of contamination) recognizing alloDC, with or without recognition of third-party EBV-LCL, was analyzed using a panel of skin- derived fibroblasts and HeLa cells expressing the target- ed mismatched HLA-DP alleles (Online Supplementary Figure S6A). DC and EBV-LCL were used as controls. A significant proportion (12-63%, median 53%) of the allo- HLA-DP-restricted T-cell clones showed restricted reac- tivity against DC, with (first recognition profile column in Table 2) or without (second recognition profile column in Table 2) EBV-LCL recognition, but not against fibrob- lasts or HeLa cells expressing the targeted mismatched HLA-DP allele, whereas the other HLA-DP-restricted clones showed a broad recognition pattern against all stimulator cells expressing the mismatched HLA-DP allele (20-80%, median 38%, third recognition profile column in Table 2), or against a selection of the tested stimulator cells (0-28%, median 7%, fourth and fifth recognition profile columns in Table 2) (the reactivity of representative clones of response 4 is shown in Online Supplementary Figure S6B-F). A selection of allo-HLA-DP- restricted T-cell clones was tested for their cytotoxic capacity and was found to be cytotoxic with variable efficiency (data not shown). Similar reactivity patterns were observed for the HLA-DQB1-restricted clones derived from the immune response mounted in response 5 (Table 2). These data illustrate that the allo-HLA-DP- and allo-HLA-DQ-specific T-cell repertoire contains T cells with various cell-lineage-specific recognition pat-
terns, as well as T cells that recognize all cells expressing the targeted mismatched HLA-DP or HLA-DQ allele, irrespectively of their cell lineage.
The allo-HLA-DP specific T-cell repertoire contains T cells that are able to recognize primary hematopoietic malignant cells, without coinciding reactivity against non-hematopoietic cells
To investigate whether the allo-HLA-DP-specific T-cell repertoire contains T cells that harbor the potential to rec- ognize primary malignant cells without recognition of var- ious non-hematopoietic cells, a selected number of T-cell clones (response 2, n=9; response 3, n=6; response 4, n=10; and response 5a, n=10) were tested against a panel of third-party primary malignant hematopoietic cell sam- ples (acute myeloid leukemia, 13 samples; B-cell acute lymphoblastic leukemia, 9 samples; and chronic lympho- cytic leukemia, 6 samples) expressing the targeted mis- matched allele (HLA-DP expression shown in Online Supplementary Figure S7A,B), and against a panel of non- hematopoietic cell lines derived from different GvHD tar- get organs (skin-derived fibroblasts, HeLa cells, colon car- cinoma, and biliary epithelial cell lines) expressing the tar- geted mismatched HLA-DP allele. The HLA-DP-restricted T-cell clones that previously showed a broad recognition pattern recognized all target-HLA-DP-expressing malig- nant and non-hematopoietic cell types (clone response 4, as a representative example, is shown in Online Supplementary Figure S7C-I).
The HLA-DP-restricted T-cell clones that showed recog- nition of DC and EBV-LCL recognized malignant hematopoietic cell subsets of different lineages (represen- tative HLA-DPB1*03:01-restricted clone in Figure 3A), but showed no reactivity against skin-derived fibroblasts and different non-hematopoietic cells expressing the target HLA-DP molecule (representative HLA-DPB1*03:01- restricted clone in Figure 3B). The HLA-DP-restricted T- cell clones that previously showed restricted recognition of DC, but not of EBV-LCL, showed only recognition of acute myeloid leukemia, but not of malignant B cells (e.g. chronic lymphocytic leukemia or B-cell acute lymphoblas- tic leukemia) (a representative clone from response 4 is shown in Figure 3C and from responses 2 and 5 in Online Supplementary Figure S8) and non-hematopoietic cells (e.g. fibroblasts and cell lines) (a representative clone from response 4 is shown in Figure 3D).
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