The Journal of Immunology, Vol 138, Issue 12 4236-4242, Copyright © 1987 by American Association of Immunologists

ARTICLES

Monoclonal antibodies to human recombinant interleukin 1 (IL 1)beta: quantitation of IL 1 beta and inhibition of biological activity

JS Kenney, MP Masada, EM Eugui, BM Delustro, MA Mulkins and AC Allison

Monoclonal antibodies (McAb) were developed to the Mr 17,500 form of human recombinant interleukin 1, IL 1 beta. Four McAb have been identified that inhibit the biological activity of IL 1 beta. McAb H34 and H67, at 1 microgram/ml (6 X 10(-9) M), completely inhibit the capacity of 1 ng/ml (6 X 10(-11) M) recombinant IL 1 beta to stimulate the proliferation of murine thymocytes or human fibroblasts in vitro. McAb H6 and H21 are approximately 10-fold less potent, and completely inhibit IL 1 beta activity at 10 micrograms/ml (6 X 10(-8) M) in both assays. The McAb do not have a significant effect on the biological activity of human recombinant IL 1 alpha in either assay. These McAb block the binding of recombinant [125I]IL 1 beta to IL 1 receptors on mouse 3T3 fibroblasts and have affinity constants for IL 1 beta in the range of 10(9) to 10(10) liters/mol. Competition studies suggest that two nonoverlapping epitopes on the IL 1 beta molecule are recognized by the McAb. H6 and H34 recognize one epitope, and H21 and H67 another. McAb H6 and H67 have been used together in a two-site ELISA to detect IL 1 beta. The sensitivity of the ELISA, which is 15 pg/ml (0.86 pM), approaches the limit of sensitivity of the thymocyte proliferation assay. The ELISA and thymocyte proliferation assay were used to quantitate IL 1 beta in E. coli LPS-stimulated human monocyte culture supernatants (HMCS). The level of IL 1 beta detected by ELISA in culture supernatants from eight donors ranged from 1.7 to 5.6 ng/ml, with a mean value of approximately 3 ng/ml. By comparison, the thymocyte proliferation assay gave levels of IL 1 in HMCS that were eight fold higher when quantitated by using recombinant IL 1 beta as a standard. This discrepancy with the bioassay used was reflected by the three fold higher maximum stimulation of thymocyte proliferation by HMCS as compared with recombinant IL 1 alpha or IL 1 beta, and only 45% inhibition of HMCS IL 1 activity by McAb. Thus, factors other than IL 1 beta account for the IL 1-like activity in monocyte culture supernatant as measured by the bioassay. The ILB1 McAb and ELISA allow for the first time-sensitive, accurate, and convenient quantitation of IL 1 beta levels in biological fluids or specimens.

This article has been cited by other articles:

				M. Locati, U. Deuschle, M. L. Massardi, F. O. Martinez, M. Sironi, S. Sozzani, T. Bartfai, and A. Mantovani Analysis of the Gene Expression Profile Activated by the CC Chemokine Ligand 5/RANTES and by Lipopolysaccharide in Human Monocytes J. Immunol., April 1, 2002; 168(7): 3557 - 3562. [Abstract] [Full Text] [PDF]

				M. I. Ndubuisi, K. Patel, R. J. Rayanade, A. Mittelman, L. T. May, and P. B. Sehgal Distinct Classes of Chaperoned IL-6 in Human Blood: Differential Immunological and Biological Availability J. Immunol., January 1, 1998; 160(1): 494 - 501. [Abstract] [Full Text] [PDF]

				T. Van Der Poll and S. F. Lowry Epinephrine inhibits endotoxin-induced IL-1beta production: roles of tumor necrosis factor-alpha and IL-10 Am J Physiol Regulatory Integrative Comp Physiol, December 1, 1997; 273(6): R1885 - R1890. [Abstract] [Full Text] [PDF]

				C. Kim, C. Schinkel, D. Fuchs, J. Stadler, A. Walz, S. Zedler, G. H. v. Donnersmarck, and E. Faist Interleukin-13 Effectively Down-regulates the Monocyte Inflammatory Potential During Traumatic Stress Arch Surg, December 1, 1995; 130(12): 1330 - 1336. [Abstract] [PDF]

				M. A. Boermeester, P. A. M. van Leeuwen, S. M. Coyle, G. J. Wolbink, C. E. Hack, and S. F. Lowry Interleukin-1 Blockade Attenuates Mediator Release and Dysregulation of the Hemostatic Mechanism During Human Sepsis Arch Surg, July 1, 1995; 130(7): 739 - 748. [Abstract] [PDF]