Dendritic cells (DC) need to be stimulated before they can function to initiate immune responses. This study investigates whether microparticles loaded with antibodies specific for selected receptors expressed by DC can induce stimulation of these cells. Plain microparticles were compared with microparticles which were surface-loaded with specific antibodies for human CD40, Fc(gamma), alpha(v)beta3 and alpha(v)beta5 integrin receptors. The antibodies were either physically adsorbed or covalently linked to the microparticle surface. Anti-CD40 antibody and human IgG immobilised on the surface of microparticles induced enhanced DC maturation and activation as expressed by CD83 and CD86 upregulation. IL-12 secretion was induced at a detectable but relatively low level. Both anti-integrin antibodies (anti-alpha(v)beta3 and anti-alpha(v)beta5) induced comparable and considerable maturation of DC, but only anti-alpha(v)beta3 antibody induced significant activation of DC, whereas anti-alpha(v)beta5 did not. The stimulatory effects were most pronounced by employing microparticles with covalently linked antibodies, but were also observed to a minor extent when the antibodies were physically adsorbed to polystyrene and biodegradable poly(lactide-co-glycolide) microparticles. Engineering of microparticles by surface conjugation of specific ligands to stimulate DC may increase the effectiveness of microparticulate vaccine delivery systems.
The problem of scattering of surface waves obliquely incident on a submerged fixed vertical plate is solved approximately for a small angle of incidence by reducing it to the solution of an integral equation. The correction to the reflection and transmission coefficients over their normal incidence values for a small angle of incidence are obtained. For different values of the incident angle these coefficients are evaluated numerically, taking particular values of the wave number and the depth of the plate, and represented graphically.
Using the multipoles method, we formulate the problems of radiation (both heave and sway) of water waves by a submerged sphere in deep as well as in uniform finite depth water with an ice-cover, with the ice-cover being modelled as an elastic plate of very small thickness. In each case this leads to an infinite system of linear equations which are solved numerically by standard techniques. The added-mass and damping coefficients for a heaving and swaying sphere are obtained and depicted graphically against the wave number for various values of the radius of the submerged sphere and flexural rigidity of the ice-cover to show the effect of the presence of ice-cover on these quantities. When the flexural rigidity is taken to be zero, the numerical results for the added-mass and damping coefficient for water with a free surface are recovered.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.