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 701 to 800, in pages of 100, sorted by symbol for reading. The order carries no ranking.
| Gene | Authority id | Mapping file id | Evidence codes |
|---|---|---|---|
| GeneOS9 | AuthorityHGNC:16994 | Mapping file id10956 NCBI file | EvidenceTAS |
| GeneOSBPL1A | AuthorityHGNC:16398 | Mapping file id114876 NCBI file | EvidenceTAS |
| GeneOSCAR | AuthorityHGNC:29960 | Mapping file id126014 NCBI file | EvidenceTAS |
| GeneOST4 | AuthorityHGNC:32483 | Mapping file id100128731 NCBI file | EvidenceTAS |
| GeneOSTC | AuthorityHGNC:24448 | Mapping file id58505 NCBI file | EvidenceTAS |
| GenePAF1 | AuthorityHGNC:25459 | Mapping file id54623 NCBI file | EvidenceIEA |
| GenePAG1 | AuthorityHGNC:30043 | Mapping file id55824 NCBI file | EvidenceTAS |
| GenePAGR1 | AuthorityHGNC:28707 | Mapping file id79447 NCBI file | EvidenceIEA |
| GenePAK1 | AuthorityHGNC:8590 | Mapping file id5058 NCBI file | EvidenceTAS |
| GenePAK2 | AuthorityHGNC:8591 | Mapping file id5062 NCBI file | EvidenceTAS |
| GenePAK3 | AuthorityHGNC:8592 | Mapping file id5063 NCBI file | EvidenceTAS |
| GenePAX5 | AuthorityHGNC:8619 | Mapping file id5079 NCBI file | EvidenceIEA |
| GenePAXIP1 | AuthorityHGNC:8624 | Mapping file id22976 NCBI file | EvidenceIEA |
| GenePCNA | AuthorityHGNC:8729 | Mapping file id5111 NCBI file | EvidenceIEA, TAS |
| GenePDCD1 | AuthorityHGNC:8760 | Mapping file id5133 NCBI file | EvidenceTAS |
| GenePDCD1LG2 | AuthorityHGNC:18731 | Mapping file id80380 NCBI file | EvidenceTAS |
| GenePDIA3 | AuthorityHGNC:4606 | Mapping file id2923 NCBI file | EvidenceIEA, TAS |
| GenePDPK1 | AuthorityHGNC:8816 | Mapping file id5170 NCBI file | EvidenceTAS |
| GenePIANP | AuthorityHGNC:25338 | Mapping file id196500 NCBI file | EvidenceTAS |
| GenePIK3AP1 | AuthorityHGNC:30034 | Mapping file id118788 NCBI file | EvidenceIEA, TAS |
| GenePIK3C3 | AuthorityHGNC:8974 | Mapping file id5289 NCBI file | EvidenceTAS |
| GenePIK3CA | AuthorityHGNC:8975 | Mapping file id5290 NCBI file | EvidenceTAS |
| GenePIK3CB | AuthorityHGNC:8976 | Mapping file id5291 NCBI file | EvidenceTAS |
| GenePIK3CD | AuthorityHGNC:8977 | Mapping file id5293 NCBI file | EvidenceIEA, TAS |
| GenePIK3CG | AuthorityHGNC:8978 | Mapping file id5294 NCBI file | EvidenceTAS |
| GenePIK3R1 | AuthorityHGNC:8979 | Mapping file id5295 NCBI file | EvidenceIEA, TAS |
| GenePIK3R2 | AuthorityHGNC:8980 | Mapping file id5296 NCBI file | EvidenceTAS |
| GenePIK3R3 | AuthorityHGNC:8981 | Mapping file id8503 NCBI file | EvidenceTAS |
| GenePIK3R4 | AuthorityHGNC:8982 | Mapping file id30849 NCBI file | EvidenceTAS |
| GenePIK3R5 | AuthorityHGNC:30035 | Mapping file id23533 NCBI file | EvidenceTAS |
| GenePIK3R6 | AuthorityHGNC:27101 | Mapping file id146850 NCBI file | EvidenceTAS |
| GenePILRA | AuthorityHGNC:20396 | Mapping file id29992 NCBI file | EvidenceTAS |
| GenePILRB | AuthorityHGNC:18297 | Mapping file id29990 NCBI file | EvidenceTAS |
| GenePJA1 | AuthorityHGNC:16648 | Mapping file id64219 NCBI file | EvidenceTAS |
| GenePJA2 | AuthorityHGNC:17481 | Mapping file id9867 NCBI file | EvidenceTAS |
| GenePLCG1 | AuthorityHGNC:9065 | Mapping file id5335 NCBI file | EvidenceTAS |
| GenePLCG2 | AuthorityHGNC:9066 | Mapping file id5336 NCBI file | EvidenceIEA, TAS |
| GenePMS2 | AuthorityHGNC:9122 | Mapping file id5395 NCBI file | EvidenceTAS |
| GenePOLD2 | AuthorityHGNC:9176 | Mapping file id5425 NCBI file | EvidenceIEA, TAS |
| GenePOLD3 | AuthorityHGNC:20932 | Mapping file id10714 NCBI file | EvidenceIEA, TAS |
| GenePOLH | AuthorityHGNC:9181 | Mapping file id5429 NCBI file | EvidenceIEA, TAS |
| GenePOLI | AuthorityHGNC:9182 | Mapping file id11201 NCBI file | EvidenceIEA, TAS |
| GenePOLR2A | AuthorityHGNC:9187 | Mapping file id5430 NCBI file | EvidenceIEA |
| GenePOLR2B | AuthorityHGNC:9188 | Mapping file id5431 NCBI file | EvidenceIEA |
| GenePOLR2C | AuthorityHGNC:9189 | Mapping file id5432 NCBI file | EvidenceIEA |
| GenePOLR2D | AuthorityHGNC:9191 | Mapping file id5433 NCBI file | EvidenceIEA |
| GenePOLR2E | AuthorityHGNC:9192 | Mapping file id5434 NCBI file | EvidenceIEA |
| GenePOLR2F | AuthorityHGNC:9193 | Mapping file id5435 NCBI file | EvidenceIEA |
| GenePOLR2G | AuthorityHGNC:9194 | Mapping file id5436 NCBI file | EvidenceIEA |
| GenePOLR2H | AuthorityHGNC:9195 | Mapping file id5437 NCBI file | EvidenceIEA |
| GenePOLR2I | AuthorityHGNC:9196 | Mapping file id5438 NCBI file | EvidenceIEA |
| GenePOLR2J | AuthorityHGNC:9197 | Mapping file id5439 NCBI file | EvidenceIEA |
| GenePOLR2K | AuthorityHGNC:9198 | Mapping file id5440 NCBI file | EvidenceIEA |
| GenePOLR2L | AuthorityHGNC:9199 | Mapping file id5441 NCBI file | EvidenceIEA |
| GenePPIA | AuthorityHGNC:9253 | Mapping file id5478 NCBI file | EvidenceIEA |
| GenePPL | AuthorityHGNC:9273 | Mapping file id5493 NCBI file | EvidenceTAS |
| GenePPP2CA | AuthorityHGNC:9299 | Mapping file id5515 NCBI file | EvidenceTAS |
| GenePPP2CB | AuthorityHGNC:9300 | Mapping file id5516 NCBI file | EvidenceTAS |
| GenePPP2R1A | AuthorityHGNC:9302 | Mapping file id5518 NCBI file | EvidenceTAS |
| GenePPP2R1B | AuthorityHGNC:9303 | Mapping file id5519 NCBI file | EvidenceTAS |
| GenePPP2R5A | AuthorityHGNC:9309 | Mapping file id5525 NCBI file | EvidenceTAS |
| GenePPP2R5B | AuthorityHGNC:9310 | Mapping file id5526 NCBI file | EvidenceTAS |
| GenePPP2R5C | AuthorityHGNC:9311 | Mapping file id5527 NCBI file | EvidenceTAS |
| GenePPP2R5D | AuthorityHGNC:9312 | Mapping file id5528 NCBI file | EvidenceTAS |
| GenePPP2R5E | AuthorityHGNC:9313 | Mapping file id5529 NCBI file | EvidenceTAS |
| GenePPP3CA | AuthorityHGNC:9314 | Mapping file id5530 NCBI file | EvidenceIEA, TAS |
| GenePPP3CB | AuthorityHGNC:9315 | Mapping file id5532 NCBI file | EvidenceIEA, TAS |
| GenePPP3R1 | AuthorityHGNC:9317 | Mapping file id5534 NCBI file | EvidenceIEA, TAS |
| GenePRDM1 | AuthorityHGNC:9346 | Mapping file idENSG00000057657 Ensembl file | EvidenceIEA |
| GenePRKAA1 | AuthorityHGNC:9376 | Mapping file id5562 NCBI file | EvidenceTAS |
| GenePRKAA2 | AuthorityHGNC:9377 | Mapping file id5563 NCBI file | EvidenceTAS |
| GenePRKAB1 | AuthorityHGNC:9378 | Mapping file id5564 NCBI file | EvidenceTAS |
| GenePRKAB2 | AuthorityHGNC:9379 | Mapping file id5565 NCBI file | EvidenceTAS |
| GenePRKACA | AuthorityHGNC:9380 | Mapping file id5566 NCBI file | EvidenceTAS |
| GenePRKACB | AuthorityHGNC:9381 | Mapping file id5567 NCBI file | EvidenceTAS |
| GenePRKACG | AuthorityHGNC:9382 | Mapping file id5568 NCBI file | EvidenceTAS |
| GenePRKAG1 | AuthorityHGNC:9385 | Mapping file id5571 NCBI file | EvidenceTAS |
| GenePRKAG2 | AuthorityHGNC:9386 | Mapping file id51422 NCBI file | EvidenceTAS |
| GenePRKAG3 | AuthorityHGNC:9387 | Mapping file id53632 NCBI file | EvidenceTAS |
| GenePRKCB | AuthorityHGNC:9395 | Mapping file id5579 NCBI file | EvidenceTAS |
| GenePRKCQ | AuthorityHGNC:9410 | Mapping file id5588 NCBI file | EvidenceTAS |
| GenePRKG1 | AuthorityHGNC:9414 | Mapping file id5592 NCBI file | EvidenceTAS |
| GenePRKN | AuthorityHGNC:8607 | Mapping file id5071 NCBI file | EvidenceTAS |
| GenePRR5 | AuthorityHGNC:31682 | Mapping file id55615 NCBI file | EvidenceTAS |
| GenePSMA1 | AuthorityHGNC:9530 | Mapping file id5682 NCBI file | EvidenceIEA, TAS |
| GenePSMA2 | AuthorityHGNC:9531 | Mapping file id5683 NCBI file | EvidenceIEA, TAS |
| GenePSMA3 | AuthorityHGNC:9532 | Mapping file id5684 NCBI file | EvidenceIEA, TAS |
| GenePSMA4 | AuthorityHGNC:9533 | Mapping file id5685 NCBI file | EvidenceIEA, TAS |
| GenePSMA5 | AuthorityHGNC:9534 | Mapping file id5686 NCBI file | EvidenceIEA, TAS |
| GenePSMA6 | AuthorityHGNC:9535 | Mapping file id5687 NCBI file | EvidenceIEA, TAS |
| GenePSMA7 | AuthorityHGNC:9536 | Mapping file id5688 NCBI file | EvidenceIEA, TAS |
| GenePSMB1 | AuthorityHGNC:9537 | Mapping file id5689 NCBI file | EvidenceIEA, TAS |
| GenePSMB10 | AuthorityHGNC:9538 | Mapping file id5699 NCBI file | EvidenceTAS |
| GenePSMB2 | AuthorityHGNC:9539 | Mapping file id5690 NCBI file | EvidenceIEA, TAS |
| GenePSMB3 | AuthorityHGNC:9540 | Mapping file id5691 NCBI file | EvidenceIEA, TAS |
| GenePSMB4 | AuthorityHGNC:9541 | Mapping file id5692 NCBI file | EvidenceIEA, TAS |
| GenePSMB5 | AuthorityHGNC:9542 | Mapping file id5693 NCBI file | EvidenceIEA, TAS |
| GenePSMB6 | AuthorityHGNC:9543 | Mapping file id5694 NCBI file | EvidenceIEA, TAS |
| GenePSMB7 | AuthorityHGNC:9544 | Mapping file id5695 NCBI file | EvidenceIEA, TAS |
| GenePSMB8 | AuthorityHGNC:9545 | Mapping file id5696 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.