The Act1 D10N missense variant impairs CD40 signaling in human B-cells

Published online:


The TRAF3IP2 gene resides within one of at least 63 psoriasis susceptibility loci and encodes Act1, an adapter protein involved in IL-17 receptor and CD40 signaling pathways. TRAF3IP2 is distinctive (among <10% of candidate susceptibility genes) in that a strongly disease-associated variant encodes a missense SNP predicted to be functionally relevant (SNP rs33980500 C/T encoding Act1 pD10N). As assessed by flow cytometry, Act1 protein was expressed at the highest levels in monocytes, with lower levels in T-cells and B-cells. However, monocytes, T-cells and B-cells failed to respond to IL-17A stimulation of PBMC, as measured by flow cytometric determination of NF-κB phospho-p65. As an alternative stimulus, we treated PBMCs with trimerized recombinant human CD40L and assessed p65, p38 and Erk phosphorylation in CD19+ B-cells as a function of D10N genotype. The increase of phosphorylated p65, p38, and Erk was well-correlated across individuals, and CD40L-induced phosphorylation of p65, p38, and Erk was significantly attenuated in B-cells from Act1 D10N homozygotes, compared to heterozygotes and nullizygotes. Our results indicate that the Act1 D10N variant is a relevant genetic determinant of CD40L responsiveness in human B-cells, with the risk allele being associated with lower B-cell responses in an acute signaling context.

  • Subscribe to Genes and Immunity for full access:



Additional access options:

Already a subscriber?  Log in  now or  Register  for online access.


  1. 1.

    Gudjonsson JE, Elder JT. Psoriasis. In: Goldsmith L, Katz SI, Gilchrest BA, Paller AS, Woolf K, Leffell DJ, editors. Dermatology in general medicine. 8th edn; Vol. 1. New York: McGraw-Hill; 2012. p. 197–231.

  2. 2.

    Kim J, Krueger JG. The immunopathogenesis of psoriasis. Dermatol Clin. 2015;33:13–23.

  3. 3.

    Martin DA, Towne JE, Kricorian G, Klekotka P, Gudjonsson JE, Krueger JG, et al. The emerging role of IL-17 in the pathogenesis of psoriasis: preclinical and clinical findings. J Invest Dermatol. 2013;133:17–26.

  4. 4.

    Johansen C, Usher PA, Kjellerup RB, Lundsgaard D, Iversen L, Kragballe K. Characterization of the interleukin-17 isoforms and receptors in lesional psoriatic skin. Br J Dermatol. 2009;160: 319–24.

  5. 5.

    Guttman-Yassky E, Lowes MA, Fuentes-Duculan J, Zaba LC, Cardinale I, Nograles KE, et al. Low expression of the IL-23/Th17 pathway in atopic dermatitis compared to psoriasis. J Immunol. 2008;181:7420–7.

  6. 6.

    Johnston A, Fritz Y, Dawes SM, Diaconu D, Al-Attar PM, Guzman AM, et al. Keratinocyte overexpression of IL-17C promotes psoriasiform skin inflammation. J Immunol. 2013;190:2252–62.

  7. 7.

    Chang SH, Park H, Dong C. Act1 adaptor protein is an immediate and essential signaling component of interleukin-17 receptor. J Biol Chem. 2006;281:35603–7.

  8. 8.

    Qian Y, Liu C, Hartupee J, Altuntas CZ, Gulen MF, Jane-Wit D, et al. The adaptor Act1 is required for interleukin 17-dependent signaling associated with autoimmune and inflammatory disease. Nat Immunol. 2007;8:247–56.

  9. 9.

    Sonder SU, Saret S, Tang W, Sturdevant DE, Porcella SF, Siebenlist U. IL-17-induced NF-kappaB activation via CIKS/Act1: physiologic significance and signaling mechanisms. J Biol Chem. 2011;286:12881–90.

  10. 10.

    Liu C, Qian W, Qian Y, Giltiay NV, Lu Y, Swaidani S, et al. Act1, a U-box E3 ubiquitin ligase for IL-17 signaling. Sci Signal. 2009;2:ra63.

  11. 11.

    Luo Q, Sun Y, Liu W, Qian C, Jin B, Tao F, et al. A novel disease-modifying antirheumatic drug, iguratimod, ameliorates murine arthritis by blocking IL-17 signaling, distinct from methotrexate and leflunomide. J Immunol. 2013;191:4969–78.

  12. 12.

    Qian Y, Qin J, Cui G, Naramura M, Snow EC, Ware CF, et al. Act1, a negative regulator in CD40- and BAFF-mediated B cell survival. Immunity. 2004;21:575–87.

  13. 13.

    Edwards SL, Beesley J, French JD, Dunning AM. Beyond GWASs: illuminating the dark road from association to function. Am J Hum Genet. 2013;93:779–97.

  14. 14.

    Ellinghaus E, Ellinghaus D, Stuart PE, Nair RP, Debrus S, Raelson JV, et al. Genome-wide association study identifies a psoriasis susceptibility locus at TRAF3IP2. Nat Genet. 2010;42:991–5.

  15. 15.

    Huffmeier U, Uebe S, Ekici AB, Bowes J, Giardina E, Korendowych E, et al. Common variants at TRAF3IP2 are associated with susceptibility to psoriatic arthritis and psoriasis. Nat Genet. 2010;42:996–9.

  16. 16.

    Genetic Analysis of Psoriasis C, the Wellcome Trust Case Control C, Strange A, Capon F, Spencer CC, Knight J, et al. A genome-wide association study identifies new psoriasis susceptibility loci and an interaction between HLA-C and ERAP1. Nat Genet. 2010;42:985–90.

  17. 17.

    Stuart PE, Nair RP, Tsoi LC, Tejasvi T, Das S, Kang HM, et al. Genome-wide association analysis of psoriatic arthritis and cutaneous psoriasis reveals differences in their genetic architecture. Am J Hum Genet. 2015;97:816–36.

  18. 18.

    Ghosh S, Hayden MS. Celebrating 25 years of NF-kappaB research. Immunol Rev. 2012;246:5–13.

  19. 19.

    Gaffen SL. Structure and signalling in the IL-17 receptor family. Nat Rev Immunol. 2009;9:556–67.

  20. 20.

    Hayden MS, Ghosh S. Regulation of NF-kappaB by TNF family cytokines. Semin Immunol. 2014;26:253–66.

  21. 21.

    Giltiay NV, Lu Y, Cullen JL, Jorgensen TN, Shlomchik MJ, Li X. Spontaneous loss of tolerance of autoreactive B cells in Act1-deficient rheumatoid factor transgenic mice. J Immunol. 2013;191:2155–63.

  22. 22.

    Claudio E, Sonder SU, Saret S, Carvalho G, Ramalingam TR, Wynn TA, et al. The adaptor protein CIKS/Act1 is essential for IL-25-mediated allergic airway inflammation. J Immunol. 2009;182:1617–30.

  23. 23.

    Craxton A, Shu G, Graves JD, Saklatvala J, Krebs EG, Clark EA. p38 MAPK is required for CD40-induced gene expression and proliferation in B lymphocytes. J Immunol. 1998;161: 3225–36.

  24. 24.

    Li YY, Baccam M, Waters SB, Pessin JE, Bishop GA, Koretzky GA. CD40 ligation results in protein kinase C-independent activation of ERK and JNK in resting murine splenic B cells. J Immunol. 1996;157:1440–7.

  25. 25.

    Nair RP, Duffin KC, Helms C, Ding J, Stuart PE, Goldgar D, et al. Genome-wide scan reveals association of psoriasis with IL-23 and NF-kappaB pathways. Nat Genet. 2009;41:199–204.

  26. 26.

    Tsoi LC, Spain SL, Ellinghaus E, Stuart PE, Capon F, Knight J, et al. Enhanced meta-analysis and replication studies identify five new psoriasis susceptibility loci. Nat Commun. 2015;6:7001.

  27. 27.

    Tsoi LC, Spain SL, Knight J, Ellinghaus E, Stuart PE, Capon F, et al. Identification of 15 new psoriasis susceptibility loci highlights the role of innate immunity. Nat Genet. 2012;44:1341–8.

  28. 28.

    Wang C, Wu L, Bulek K, Martin BN, Zepp JA, Kang Z, et al. The psoriasis-associated D10N variant of the adaptor Act1 with impaired regulation by the molecular chaperone hsp90. Nat Immunol. 2013;14:72–81.

  29. 29.

    Boisson B, Wang C, Pedergnana V, Wu L, Cypowyj S, Rybojad M, et al. An ACT1 mutation selectively abolishes interleukin-17 responses in humans with chronic mucocutaneous candidiasis. Immunity. 2013;39:676–86.

  30. 30.

    Shahrara S, Pickens SR, Mandelin AM 2nd, Karpus WJ, Huang Q, Kolls JK, et al. IL-17-mediated monocyte migration occurs partially through CC chemokine ligand 2/monocyte chemoattractant protein-1 induction. J Immunol. 2010;184:4479–87.

  31. 31.

    Wang CQF, Suárez-Fariñas M, Nograles KE, Mimoso CA, Shrom D, Dow ER, Heffernan MP, Hoffman RW, Krueger JG, IL-17 induces inflammation-associated gene products in blood monocytes, and treatment with ixekizumab reduces their expression in psoriasis patient blood. J Invest Dermatol. 2014;134:2990–3.

  32. 32.

    Kehry MR. CD40-mediated signaling in B cells. Balancing cell survival, growth, and death. J Immunol. 1996;156:2345–8.

  33. 33.

    Wennhold K, Shimabukuro-Vornhagen A, Theurich S, von Bergwelt-Baildon M. CD40-activated B cells as antigen-presenting cells: the final sprint toward clinical application. Expert Rev Vaccin. 2013;12:631–7.

  34. 34.

    Hobeika E, Nielsen PJ, Medgyesi D. Signaling mechanisms regulating B-lymphocyte activation and tolerance. J Mol Med (Berl). 2015;93:143–58.

  35. 35.

    Yoshizaki A, Miyagaki T, DiLillo DJ, Matsushita T, Horikawa M, Kountikov EI, et al. Regulatory B cells control T-cell autoimmunity through IL-21-dependent cognate interactions. Nature. 2012;491:264–8.

  36. 36.

    Yang M, Rui K, Wang S, Lu L. Regulatory B cells in autoimmune diseases. Cell Mol Immunol. 2013;10:122–32.

  37. 37.

    Hilgenberg E, Shen P, Dang VD, Ries S, Sakwa I, Fillatreau S. Interleukin-10-producing B cells and the regulation of immunity. Curr Top Microbiol Immunol. 2014;380:69–92.

  38. 38.

    Austin ED, Rock MT, Mosse CA, Vnencak-Jones CL, Yoder SM, Robbins IM, et al. T lymphocyte subset abnormalities in the blood and lung in pulmonary arterial hypertension. Respir Med. 2010;104:454–62.

Download references


We thank the volunteers who provided blood samples for this study, and Dr. Andrew Johnston for advice on flow cytometry. This research was supported by National Institutes of Health (NIH) R01 grants AR042742, AR050511, AR054966, AR062382, and AR065183 to JTE. We also acknowledge generous support from the Dawn and Dudley Holmes Memorial Fund and the Babcock Endowment Fund to the Department of Dermatology at the University of Michigan. JTE is supported by the Ann Arbor Veterans Affairs Hospital.

Author information

Author notes

  1. Ning Yu and Sylviane Lambert contributed equally to this work


  1. Department of Dermatology, University of Michigan, Ann Arbor, MI, USA

    • Ning Yu
    • , Sylviane Lambert
    • , Joshua Bornstein
    • , Rajan P. Nair
    • , Charlotta Enerbäck
    •  & James T. Elder
  2. Department of Dermatology, Shanghai Skin Disease Hospital, Shanghai, China

    • Ning Yu
  3. Department of Dermatology, Linköping University, Linköping, Sweden

    • Charlotta Enerbäck
  4. Ann Arbor Veterans Affairs Health System, Ann Arbor, MI, USA

    • James T. Elder


  1. Search for Ning Yu in:

  2. Search for Sylviane Lambert in:

  3. Search for Joshua Bornstein in:

  4. Search for Rajan P. Nair in:

  5. Search for Charlotta Enerbäck in:

  6. Search for James T. Elder in:

Conflict of interest

The authors declare that they have no competing interests.

Corresponding authors

Correspondence to Ning Yu or James T. Elder.