Pathway Human Homo sapiens
Adaptive Immune System
R-HSA-1280218 in Reactome release 97: under Immune System, with 1,149 genes placed in it by the mapping files and 9 child pathways in the hierarchy.
The same number in the other species
Reactome writes the mouse and rat events it infers from a human pathway under the human number with the species token. A door opens only where that species' own list in this release holds the id: R-MMU-1280218 (mouse), R-RNO-1280218 (rat). Whether the event was inferred from this one is what the record says.
01The record
Reactome's own record of this pathway
What this tells you
The pathway list, the hierarchy and the genes on this page are read from the files Reactome publishes for Reactome release 97, built into this site on 2026-09-09: the pathway list, the hierarchy relationship file and the two gene mapping files. The record card is the one live read, Reactome's own record of this pathway.
Reactome's download page describes the mapping files: Mapping files link the source database identifier to the lowest level pathway diagram or subset of the pathway, all levels of the pathway hierarchy or database identifier to all reactions.
[R13] The gene list here is the all-levels mapping of NCBI Gene ids, filled from the all-levels mapping of Ensembl ids where the NCBI file has no row for a gene; each row names which file it came from by the shape of its source id. Each row carries the evidence codes the file writes for it, as written and unranked, and both where the file writes both; no page of Reactome's documentation the survey read defines the codes, so this page does not expand them. A gene id the identity files do not name is kept as the source's own id with no door rather than turned into a symbol.
On citing what a search finds, Reactome says: It should be remembered that while we strive to contain the most current and accurate data, Reactome should not be used in citations where other primary sources of information are available.
[R12] The record card prints the literature Reactome attaches to a curated pathway for that reason. The data are public domain: All data in the Reactome database and files derived from that data are licensed under the Creative Commons Public Domain Dedication (CC0). User may copy, modify, and distribute these data, even for commercial purposes, without asking for permission. Attribution is encouraged but not required.
[R10] The pathway illustrations are licensed apart, under CC BY 4.0, and none is shown here.
A gene on this list is one Reactome places in this pathway in this release, and that is all the row says: it does not say the gene is expressed in a tissue or associated with a disease, which are the other two explorers' questions, read from other sources. Reactome's papers of record are [R01] [R02].
- [R01] Ragueneau E, Gong C, Sinquin P, Sevilla C, Beavers D, Grentner A, et al. (2026). The Reactome Knowledgebase 2026. Nucleic Acids Research 54:D673-D681. PMID 41251150, doi 10.1093/nar/gkaf1223.
- [R02] Milacic M, Beavers D, Conley P, Gong C, Gillespie M, Griss J, et al. (2024). The Reactome Pathway Knowledgebase 2024. Nucleic Acids Research 52:D672-D678. PMID 37941124, doi 10.1093/nar/gkad1025.
- [R10] Reactome, reactome.org. License Agreement. https://reactome.org/license, read 2026-09-09.
- [R12] Reactome, reactome.org. Citing us. https://reactome.org/cite, read 2026-09-09.
- [R13] Reactome, reactome.org. Download. https://reactome.org/download-data, read 2026-09-09.
02The genes
Genes Reactome places in this human pathway
The mapping files place 1,149 genes in this human pathway; showing 501 to 600, in pages of 100, sorted by symbol for reading. The order carries no ranking.
| Gene | Authority id | Mapping file id | Evidence codes |
|---|---|---|---|
| GeneIGLV1-44 | AuthorityHGNC:5879 | Mapping file idENSG00000211651 Ensembl file | EvidenceIEA, TAS |
| GeneIGLV1-47 | AuthorityHGNC:5880 | Mapping file idENSG00000211648 Ensembl file | EvidenceIEA, TAS |
| GeneIGLV1-51 | AuthorityHGNC:5882 | Mapping file idENSG00000211644 Ensembl file | EvidenceIEA, TAS |
| GeneIGLV2-11 | AuthorityHGNC:5887 | Mapping file idENSG00000211668 Ensembl file | EvidenceIEA, TAS |
| GeneIGLV2-14 | AuthorityHGNC:5888 | Mapping file idENSG00000211666 Ensembl file | EvidenceIEA, TAS |
| GeneIGLV2-23 | AuthorityHGNC:5890 | Mapping file idENSG00000211660 Ensembl file | EvidenceIEA, TAS |
| GeneIGLV2-8 | AuthorityHGNC:5895 | Mapping file idENSG00000278196 Ensembl file | EvidenceIEA, TAS |
| GeneIGLV3-1 | AuthorityHGNC:5896 | Mapping file idENSG00000211673 Ensembl file | EvidenceIEA, TAS |
| GeneIGLV3-19 | AuthorityHGNC:5903 | Mapping file idENSG00000211663 Ensembl file | EvidenceIEA, TAS |
| GeneIGLV3-21 | AuthorityHGNC:5905 | Mapping file idENSG00000211662 Ensembl file | EvidenceIEA, TAS |
| GeneIGLV3-25 | AuthorityHGNC:5908 | Mapping file idENSG00000211659 Ensembl file | EvidenceIEA, TAS |
| GeneIGLV3-27 | AuthorityHGNC:5910 | Mapping file idENSG00000211658 Ensembl file | EvidenceIEA, TAS |
| GeneIGLV6-57 | AuthorityHGNC:5927 | Mapping file idENSG00000211640 Ensembl file | EvidenceIEA, TAS |
| GeneIGLV7-43 | AuthorityHGNC:5929 | Mapping file idENSG00000211652 Ensembl file | EvidenceIEA, TAS |
| GeneIKBKB | AuthorityHGNC:5960 | Mapping file id3551 NCBI file | EvidenceIEA, TAS |
| GeneIKBKG | AuthorityHGNC:5961 | Mapping file id8517 NCBI file | EvidenceIEA, TAS |
| GeneIL21 | AuthorityHGNC:6005 | Mapping file id59067 NCBI file | EvidenceIEA |
| GeneIL4 | AuthorityHGNC:6014 | Mapping file id3565 NCBI file | EvidenceIEA |
| GeneINPP5D | AuthorityHGNC:6079 | Mapping file id3635 NCBI file | EvidenceTAS |
| GeneIRF1 | AuthorityHGNC:6116 | Mapping file id3659 NCBI file | EvidenceTAS |
| GeneIRF4 | AuthorityHGNC:6119 | Mapping file id3662 NCBI file | EvidenceIEA |
| GeneIRF8 | AuthorityHGNC:5358 | Mapping file id3394 NCBI file | EvidenceIEA |
| GeneITCH | AuthorityHGNC:13890 | Mapping file id83737 NCBI file | EvidenceTAS |
| GeneITGA4 | AuthorityHGNC:6140 | Mapping file id3676 NCBI file | EvidenceIEA, TAS |
| GeneITGAL | AuthorityHGNC:6148 | Mapping file id3683 NCBI file | EvidenceIEA, TAS |
| GeneITGAV | AuthorityHGNC:6150 | Mapping file id3685 NCBI file | EvidenceTAS |
| GeneITGB1 | AuthorityHGNC:6153 | Mapping file id3688 NCBI file | EvidenceIEA, TAS |
| GeneITGB2 | AuthorityHGNC:6155 | Mapping file id3689 NCBI file | EvidenceIEA, TAS |
| GeneITGB5 | AuthorityHGNC:6160 | Mapping file id3693 NCBI file | EvidenceTAS |
| GeneITGB7 | AuthorityHGNC:6162 | Mapping file id3695 NCBI file | EvidenceTAS |
| GeneITK | AuthorityHGNC:6171 | Mapping file id3702 NCBI file | EvidenceTAS |
| GeneITPR1 | AuthorityHGNC:6180 | Mapping file id3708 NCBI file | EvidenceIEA, TAS |
| GeneITPR2 | AuthorityHGNC:6181 | Mapping file id3709 NCBI file | EvidenceIEA, TAS |
| GeneITPR3 | AuthorityHGNC:6182 | Mapping file id3710 NCBI file | EvidenceIEA, TAS |
| GeneIWS1 | AuthorityHGNC:25467 | Mapping file id55677 NCBI file | EvidenceIEA |
| GeneJAK1 | AuthorityHGNC:6190 | Mapping file id3716 NCBI file | EvidenceTAS |
| GeneJAML | AuthorityHGNC:19084 | Mapping file id120425 NCBI file | EvidenceTAS |
| GeneJUN | AuthorityHGNC:6204 | Mapping file id3725 NCBI file | EvidenceTAS |
| GeneJUND | AuthorityHGNC:6206 | Mapping file id3727 NCBI file | EvidenceIEA, TAS |
| GeneKBTBD13 | AuthorityHGNC:37227 | Mapping file id390594 NCBI file | EvidenceTAS |
| GeneKBTBD6 | AuthorityHGNC:25340 | Mapping file id89890 NCBI file | EvidenceTAS |
| GeneKBTBD7 | AuthorityHGNC:25266 | Mapping file id84078 NCBI file | EvidenceTAS |
| GeneKBTBD8 | AuthorityHGNC:30691 | Mapping file id84541 NCBI file | EvidenceTAS |
| GeneKCTD6 | AuthorityHGNC:22235 | Mapping file id200845 NCBI file | EvidenceTAS |
| GeneKCTD7 | AuthorityHGNC:21957 | Mapping file id154881 NCBI file | EvidenceTAS |
| GeneKDM6A | AuthorityHGNC:12637 | Mapping file id7403 NCBI file | EvidenceIEA |
| GeneKEAP1 | AuthorityHGNC:23177 | Mapping file id9817 NCBI file | EvidenceTAS |
| GeneKIF11 | AuthorityHGNC:6388 | Mapping file id3832 NCBI file | EvidenceTAS |
| GeneKIF15 | AuthorityHGNC:17273 | Mapping file id56992 NCBI file | EvidenceTAS |
| GeneKIF18A | AuthorityHGNC:29441 | Mapping file id81930 NCBI file | EvidenceTAS |
| GeneKIF20A | AuthorityHGNC:9787 | Mapping file id10112 NCBI file | EvidenceTAS |
| GeneKIF22 | AuthorityHGNC:6391 | Mapping file id3835 NCBI file | EvidenceTAS |
| GeneKIF23 | AuthorityHGNC:6392 | Mapping file id9493 NCBI file | EvidenceTAS |
| GeneKIF26A | AuthorityHGNC:20226 | Mapping file id26153 NCBI file | EvidenceTAS |
| GeneKIF2A | AuthorityHGNC:6318 | Mapping file id3796 NCBI file | EvidenceTAS |
| GeneKIF2B | AuthorityHGNC:29443 | Mapping file id84643 NCBI file | EvidenceTAS |
| GeneKIF2C | AuthorityHGNC:6393 | Mapping file id11004 NCBI file | EvidenceTAS |
| GeneKIF3A | AuthorityHGNC:6319 | Mapping file id11127 NCBI file | EvidenceTAS |
| GeneKIF3B | AuthorityHGNC:6320 | Mapping file id9371 NCBI file | EvidenceTAS |
| GeneKIF3C | AuthorityHGNC:6321 | Mapping file id3797 NCBI file | EvidenceTAS |
| GeneKIF4A | AuthorityHGNC:13339 | Mapping file id24137 NCBI file | EvidenceTAS |
| GeneKIF4B | AuthorityHGNC:6322 | Mapping file id285643 NCBI file | EvidenceTAS |
| GeneKIF5A | AuthorityHGNC:6323 | Mapping file id3798 NCBI file | EvidenceTAS |
| GeneKIF5B | AuthorityHGNC:6324 | Mapping file id3799 NCBI file | EvidenceTAS |
| GeneKIFAP3 | AuthorityHGNC:17060 | Mapping file id22920 NCBI file | EvidenceTAS |
| GeneKIR2DL1 | AuthorityHGNC:6329 | Mapping file id3802 NCBI file | EvidenceTAS |
| GeneKIR2DL2 | AuthorityHGNC:6330 | Mapping file id3803 NCBI file | EvidenceTAS |
| GeneKIR2DL3 | AuthorityHGNC:6331 | Mapping file id3804 NCBI file | EvidenceTAS |
| GeneKIR2DL4 | AuthorityHGNC:6332 | Mapping file id3805 NCBI file | EvidenceTAS |
| GeneKIR2DS1 | AuthorityHGNC:6333 | Mapping file id3806 NCBI file | EvidenceTAS |
| GeneKIR2DS2 | AuthorityHGNC:6334 | Mapping file id100132285 NCBI file | EvidenceTAS |
| GeneKIR3DL1 | AuthorityHGNC:6338 | Mapping file id3811 NCBI file | EvidenceTAS |
| GeneKIR3DL2 | AuthorityHGNC:6339 | Mapping file id3812 NCBI file | EvidenceTAS |
| GeneKLC1 | AuthorityHGNC:6387 | Mapping file id3831 NCBI file | EvidenceTAS |
| GeneKLC2 | AuthorityHGNC:20716 | Mapping file id64837 NCBI file | EvidenceTAS |
| GeneKLC3 | AuthorityHGNC:20717 | Mapping file id147700 NCBI file | EvidenceTAS |
| GeneKLC4 | AuthorityHGNC:21624 | Mapping file id89953 NCBI file | EvidenceTAS |
| GeneKLHL11 | AuthorityHGNC:19008 | Mapping file id55175 NCBI file | EvidenceTAS |
| GeneKLHL13 | AuthorityHGNC:22931 | Mapping file id90293 NCBI file | EvidenceTAS |
| GeneKLHL2 | AuthorityHGNC:6353 | Mapping file id11275 NCBI file | EvidenceTAS |
| GeneKLHL20 | AuthorityHGNC:25056 | Mapping file id27252 NCBI file | EvidenceTAS |
| GeneKLHL21 | AuthorityHGNC:29041 | Mapping file id9903 NCBI file | EvidenceTAS |
| GeneKLHL22 | AuthorityHGNC:25888 | Mapping file id84861 NCBI file | EvidenceTAS |
| GeneKLHL25 | AuthorityHGNC:25732 | Mapping file id64410 NCBI file | EvidenceTAS |
| GeneKLHL3 | AuthorityHGNC:6354 | Mapping file id26249 NCBI file | EvidenceTAS |
| GeneKLHL41 | AuthorityHGNC:16905 | Mapping file id10324 NCBI file | EvidenceTAS |
| GeneKLHL42 | AuthorityHGNC:29252 | Mapping file id57542 NCBI file | EvidenceTAS |
| GeneKLHL5 | AuthorityHGNC:6356 | Mapping file id51088 NCBI file | EvidenceTAS |
| GeneKLHL9 | AuthorityHGNC:18732 | Mapping file id55958 NCBI file | EvidenceTAS |
| GeneKLRB1 | AuthorityHGNC:6373 | Mapping file id3820 NCBI file | EvidenceTAS |
| GeneKLRC1 | AuthorityHGNC:6374 | Mapping file id3821 NCBI file | EvidenceTAS |
| GeneKLRD1 | AuthorityHGNC:6378 | Mapping file id3824 NCBI file | EvidenceTAS |
| GeneKLRF1 | AuthorityHGNC:13342 | Mapping file id51348 NCBI file | EvidenceTAS |
| GeneKLRG1 | AuthorityHGNC:6380 | Mapping file id10219 NCBI file | EvidenceIEA |
| GeneKLRK1 | AuthorityHGNC:18788 | Mapping file id22914 NCBI file | EvidenceTAS |
| GeneKMT2A | AuthorityHGNC:7132 | Mapping file id4297 NCBI file | EvidenceTAS |
| GeneKMT2C | AuthorityHGNC:13726 | Mapping file id58508 NCBI file | EvidenceIEA, TAS |
| GeneKMT2D | AuthorityHGNC:7133 | Mapping file id8085 NCBI file | EvidenceIEA |
| GeneKRAS | AuthorityHGNC:6407 | Mapping file id3845 NCBI file | EvidenceTAS |
| GeneLAG3 | AuthorityHGNC:6476 | Mapping file id3902 NCBI file | EvidenceTAS |
Evidence codes on this page: IEA, TAS, as the mapping file writes them; a row carrying two was written twice by the file, once under each. The mapping file id says which file placed the gene: an NCBI Gene id from NCBI2Reactome_All_Levels.txt, an Ensembl gene id from Ensembl2Reactome_All_Levels.txt. The two files can disagree about a code, so a row's codes are the one file's view. Measured by this site's build over this release on 2026-09-09: of the 138,908 human pathway-gene pairs both files place, 207 (0.149 per cent, over 47 genes) carry TAS in the Ensembl file where the NCBI rows carry IEA alone.
- Reactome mapping files, the human rows for this pathway · Reactome release 97 · read · Reactome downloads"NCBI2Reactome_All_Levels.txt" and "Ensembl2Reactome_All_Levels.txt", Reactome, release 97, https://reactome.org/download-data/ (date of access 2026-09-09). Data CC0; attribution encouraged.
03The hierarchy
Parents and children in this release's hierarchy
Children
- Butyrophilin (BTN) family interactionsR-HSA-885168012 genes
- Class I MHC mediated antigen processing & presentationR-HSA-983169376 genes
- Immunoglobulin maturationR-HSA-9938026357 genes
- Immunoregulatory interactions between a Lymphoid and a non-Lymphoid cellR-HSA-198933192 genes
- MHC class II antigen presentationR-HSA-2132295126 genes
- Rap1 signallingR-HSA-39251716 genes
- Regulation of T cell activation by CD28 familyR-HSA-388841277 genes
- Signaling by the B Cell Receptor (BCR)R-HSA-983705155 genes
- TCR signalingR-HSA-202403111 genes
Reactome's hierarchy is a graph rather than a tree: a pathway can sit under more than one parent, and the gene counts are each pathway's own placements at every level under it, so a parent's count is not the sum of its children's.
- Reactome, the human pathway list and hierarchy relationship file · Reactome release 97 · read · Reactome downloads"ReactomePathways.txt" and "ReactomePathwaysRelation.txt", Reactome, release 97, https://reactome.org/download-data/ (date of access 2026-09-09). Data CC0; attribution encouraged.