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The Journal of Clinical Investigation logoLink to The Journal of Clinical Investigation
. 1991 Mar;87(3):1066–1071. doi: 10.1172/JCI115067

Human keratinocytes produce but do not process pro-interleukin-1 (IL-1) beta. Different strategies of IL-1 production and processing in monocytes and keratinocytes.

H Mizutani 1, R Black 1, T S Kupper 1
PMCID: PMC329902  PMID: 1999487

Abstract

Keratinocytes comprise the majority of cells in the epidermis, the interleukin-1 rich layer of tissue contiguous with the outside world. Keratinocytes produce IL-1 alpha and beta mRNA in vitro, but only IL-1 alpha biological activity has been identified in keratinocyte cultures. In contrast, monocytes secrete biological activities attributable to both species of IL-1. Using several monoclonal antibodies to IL-1 beta, significant amounts of IL-1 beta protein could be found in keratinocyte cultures; all of this immunoreactive IL-1 beta was in the 31-kD form. This latent cytokine has been shown to bind inefficiently to the IL-1 receptor and to be (in relative terms) biologically inactive. Chymotrypsin cleaves 31-kD IL-1 beta at Tyr 113-Val 114, generating an 18-kD IL-1 species with activity equivalent to the authentic mature IL-1 beta (NH2-terminal Ala 117). Treatment of 31-kD keratinocyte IL-1 beta with chymotrypsin also generated an 18-kD molecule and significant IL-1 activity. Monocytes contain an IL-1 convertase enzyme that cleaves the IL-1 beta promolecule at Ala 117. We demonstrate here that keratinocytes do not contain such an IL-1 convertase activity, nor do they contain any activity capable of productively processing 31-kD IL-1 beta into a biologically active form. These data suggest that keratinocytes (and other non-bone marrow-derived cells) produce IL-1 beta in an inactive form that can be processed only after leaving the cell.

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Selected References

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  1. Ansel J. C., Luger T. A., Lowry D., Perry P., Roop D. R., Mountz J. D. The expression and modulation of IL-1 alpha in murine keratinocytes. J Immunol. 1988 Apr 1;140(7):2274–2278. [PubMed] [Google Scholar]
  2. Antonelli-Orlidge A., Saunders K. B., Smith S. R., D'Amore P. A. An activated form of transforming growth factor beta is produced by cocultures of endothelial cells and pericytes. Proc Natl Acad Sci U S A. 1989 Jun;86(12):4544–4548. doi: 10.1073/pnas.86.12.4544. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Beuscher H. U., Günther C., Röllinghoff M. IL-1 beta is secreted by activated murine macrophages as biologically inactive precursor. J Immunol. 1990 Mar 15;144(6):2179–2183. [PubMed] [Google Scholar]
  4. Black R. A., Kronheim S. R., Cantrell M., Deeley M. C., March C. J., Prickett K. S., Wignall J., Conlon P. J., Cosman D., Hopp T. P. Generation of biologically active interleukin-1 beta by proteolytic cleavage of the inactive precursor. J Biol Chem. 1988 Jul 5;263(19):9437–9442. [PubMed] [Google Scholar]
  5. Black R. A., Kronheim S. R., Merriam J. E., March C. J., Hopp T. P. A pre-aspartate-specific protease from human leukocytes that cleaves pro-interleukin-1 beta. J Biol Chem. 1989 Apr 5;264(10):5323–5326. [PubMed] [Google Scholar]
  6. Black R. A., Kronheim S. R., Sleath P. R. Activation of interleukin-1 beta by a co-induced protease. FEBS Lett. 1989 Apr 24;247(2):386–390. doi: 10.1016/0014-5793(89)81376-6. [DOI] [PubMed] [Google Scholar]
  7. Blanton R. A., Kupper T. S., McDougall J. K., Dower S. Regulation of interleukin 1 and its receptor in human keratinocytes. Proc Natl Acad Sci U S A. 1989 Feb;86(4):1273–1277. doi: 10.1073/pnas.86.4.1273. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Bursten S. L., Locksley R. M., Ryan J. L., Lovett D. H. Acylation of monocyte and glomerular mesangial cell proteins. Myristyl acylation of the interleukin 1 precursors. J Clin Invest. 1988 Nov;82(5):1479–1488. doi: 10.1172/JCI113755. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Conlon P. J., Grabstein K. H., Alpert A., Prickett K. S., Hopp T. P., Gillis S. Localization of human mononuclear cell interleukin 1. J Immunol. 1987 Jul 1;139(1):98–102. [PubMed] [Google Scholar]
  10. Cseh K., Beutler B. Alternative cleavage of the cachectin/tumor necrosis factor propeptide results in a larger, inactive form of secreted protein. J Biol Chem. 1989 Sep 25;264(27):16256–16260. [PubMed] [Google Scholar]
  11. Dinarello C. A. Interleukin-1. Rev Infect Dis. 1984 Jan-Feb;6(1):51–95. doi: 10.1093/clinids/6.1.51. [DOI] [PubMed] [Google Scholar]
  12. Elias J. A., Reynolds M. M., Kotloff R. M., Kern J. A. Fibroblast interleukin 1 beta: synergistic stimulation by recombinant interleukin 1 and tumor necrosis factor and posttranscriptional regulation. Proc Natl Acad Sci U S A. 1989 Aug;86(16):6171–6175. doi: 10.1073/pnas.86.16.6171. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Fuhlbrigge R. C., Fine S. M., Unanue E. R., Chaplin D. D. Expression of membrane interleukin 1 by fibroblasts transfected with murine pro-interleukin 1 alpha cDNA. Proc Natl Acad Sci U S A. 1988 Aug;85(15):5649–5653. doi: 10.1073/pnas.85.15.5649. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Hazuda D. J., Lee J. C., Young P. R. The kinetics of interleukin 1 secretion from activated monocytes. Differences between interleukin 1 alpha and interleukin 1 beta. J Biol Chem. 1988 Jun 15;263(17):8473–8479. [PubMed] [Google Scholar]
  15. Kaye J., Gillis S., Mizel S. B., Shevach E. M., Malek T. R., Dinarello C. A., Lachman L. B., Janeway C. A., Jr Growth of a cloned helper T cell line induced by a monoclonal antibody specific for the antigen receptor: interleukin 1 is required for the expression of receptors for interleukin 2. J Immunol. 1984 Sep;133(3):1339–1345. [PubMed] [Google Scholar]
  16. Kostura M. J., Tocci M. J., Limjuco G., Chin J., Cameron P., Hillman A. G., Chartrain N. A., Schmidt J. A. Identification of a monocyte specific pre-interleukin 1 beta convertase activity. Proc Natl Acad Sci U S A. 1989 Jul;86(14):5227–5231. doi: 10.1073/pnas.86.14.5227. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Kupper T. S., Ballard D. W., Chua A. O., McGuire J. S., Flood P. M., Horowitz M. C., Langdon R., Lightfoot L., Gubler U. Human keratinocytes contain mRNA indistinguishable from monocyte interleukin 1 alpha and beta mRNA. Keratinocyte epidermal cell-derived thymocyte-activating factor is identical to interleukin 1. J Exp Med. 1986 Dec 1;164(6):2095–2100. doi: 10.1084/jem.164.6.2095. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Kupper T. S., Chua A. O., Flood P., McGuire J., Gubler U. Interleukin 1 gene expression in cultured human keratinocytes is augmented by ultraviolet irradiation. J Clin Invest. 1987 Aug;80(2):430–436. doi: 10.1172/JCI113090. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Kupper T. S., Horowitz M., Birchall N., Mizutani H., Coleman D., McGuire J., Flood P., Dower S., Lee F. Hematopoietic, lymphopoietic, and proinflammatory cytokines produced by human and murine keratinocytes. Ann N Y Acad Sci. 1988;548:262–270. doi: 10.1111/j.1749-6632.1988.tb18814.x. [DOI] [PubMed] [Google Scholar]
  20. Kupper T. S., Lee F., Birchall N., Clark S., Dower S. Interleukin 1 binds to specific receptors on human keratinocytes and induces granulocyte macrophage colony-stimulating factor mRNA and protein. A potential autocrine role for interleukin 1 in epidermis. J Clin Invest. 1988 Nov;82(5):1787–1792. doi: 10.1172/JCI113792. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Miyazono K., Hellman U., Wernstedt C., Heldin C. H. Latent high molecular weight complex of transforming growth factor beta 1. Purification from human platelets and structural characterization. J Biol Chem. 1988 May 5;263(13):6407–6415. [PubMed] [Google Scholar]
  22. Mizutani H., May L. T., Sehgal P. B., Kupper T. S. Synergistic interactions of IL-1 and IL-6 in T cell activation. Mitogen but not antigen receptor-induced proliferation of a cloned T helper cell line is enhanced by exogenous IL-6. J Immunol. 1989 Aug 1;143(3):896–901. [PubMed] [Google Scholar]
  23. Mosley B., Urdal D. L., Prickett K. S., Larsen A., Cosman D., Conlon P. J., Gillis S., Dower S. K. The interleukin-1 receptor binds the human interleukin-1 alpha precursor but not the interleukin-1 beta precursor. J Biol Chem. 1987 Mar 5;262(7):2941–2944. [PubMed] [Google Scholar]
  24. Wakefield L. M., Smith D. M., Flanders K. C., Sporn M. B. Latent transforming growth factor-beta from human platelets. A high molecular weight complex containing precursor sequences. J Biol Chem. 1988 Jun 5;263(16):7646–7654. [PubMed] [Google Scholar]
  25. Young P. R., Hazuda D. J., Simon P. L. Human interleukin 1 beta is not secreted from hamster fibroblasts when expressed constitutively from a transfected cDNA. J Cell Biol. 1988 Aug;107(2):447–456. doi: 10.1083/jcb.107.2.447. [DOI] [PMC free article] [PubMed] [Google Scholar]

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