TY - JOUR

T1 - Cell culture plastics with immobilized interleukin-4 for monocyte differentiation

AU - Hansen, Morten

AU - Hjortø, Gertrud M

AU - Met, Ozcan

AU - Jakobsen, Mogens H

AU - Svane, Inge M

AU - Larsen, Niels B

N1 - 2010 Wiley Periodicals, Inc.

PY - 2011/2

Y1 - 2011/2

N2 - Standard cell culture plastic was surface modified by passive adsorption or covalent attachment of interleukin (IL)-4 and investigated for its ability to induce differentiation of human monocytes into mature dendritic cells, a process dose-dependently regulated by IL-4. Covalent attachment of IL-4 proceeded via anthraquinone photochemistry to introduce amine functionalities at the surface followed by coupling of IL-4 through a bifunctional amine-reactive linker. X-ray photoelectron spectroscopy showed that undesirable multilayer formation of the photoactive compound could be avoided by reaction in water instead of phosphate-buffered saline. Passively adsorbed IL-4 was observed to induce differentiation to dendritic cells, but analysis of cell culture supernatants revealed that leakage of IL-4 into solution could account for the differentiation observed. Covalent attachment resulted in bound IL-4 at similar concentrations to the passive adsorption process, as measured by enzyme-linked immunosorbent assays, and the bound IL-4 did not leak into solution to any measurable extent during cell culture. However, covalently bound IL-4 was incapable of inducing monocyte differentiation. This may be caused by IL-4 denaturation or improper epitope presentation induced by the immobilization process, or by biological irresponsiveness of monocytes to IL-4 in immobilized formats.

AB - Standard cell culture plastic was surface modified by passive adsorption or covalent attachment of interleukin (IL)-4 and investigated for its ability to induce differentiation of human monocytes into mature dendritic cells, a process dose-dependently regulated by IL-4. Covalent attachment of IL-4 proceeded via anthraquinone photochemistry to introduce amine functionalities at the surface followed by coupling of IL-4 through a bifunctional amine-reactive linker. X-ray photoelectron spectroscopy showed that undesirable multilayer formation of the photoactive compound could be avoided by reaction in water instead of phosphate-buffered saline. Passively adsorbed IL-4 was observed to induce differentiation to dendritic cells, but analysis of cell culture supernatants revealed that leakage of IL-4 into solution could account for the differentiation observed. Covalent attachment resulted in bound IL-4 at similar concentrations to the passive adsorption process, as measured by enzyme-linked immunosorbent assays, and the bound IL-4 did not leak into solution to any measurable extent during cell culture. However, covalently bound IL-4 was incapable of inducing monocyte differentiation. This may be caused by IL-4 denaturation or improper epitope presentation induced by the immobilization process, or by biological irresponsiveness of monocytes to IL-4 in immobilized formats.

KW - Adsorption

KW - Anthraquinones

KW - Cell Culture Techniques

KW - Cell Differentiation

KW - Dendritic Cells

KW - Down-Regulation

KW - Enzyme-Linked Immunosorbent Assay

KW - Humans

KW - Immobilized Proteins

KW - Interleukin-4

KW - Monocytes

KW - Plastics

KW - Solutions

KW - Surface Properties

KW - Triazines

KW - Up-Regulation

KW - Journal Article

KW - Research Support, Non-U.S. Gov't

U2 - 10.1002/jbm.a.32986

DO - 10.1002/jbm.a.32986

M3 - Journal article

C2 - 21171157

VL - 96

SP - 372

EP - 383

JO - Journal of Biomedical Materials Research - Part A

JF - Journal of Biomedical Materials Research - Part A

SN - 1549-3296

IS - 2

ER -