The activity of numerous therapeutic antibodies is mediated in part by immune-mediated effector cell function following binding of the variable regions of the antibody to a specific antigen on the surface of target cells
and the interaction of the Fc moiety of the antibody with an Fc receptor on an immune effector cell .
MP-mediated increases in cAMP levels in the near-membrane compartment of target cells
is sufficient to activate known cAMP effectors.
The cell line K562, an NK-sensitive tumoral human erythroleukemia cell line, was used as target cells
. Cells were grown in RPMI-1640 (Gibco-BRL, UK) supplemented with 10% fetal bovine serum (FBS, Dutscher, France) and cultured for 24 h before cytometric analysis.
In its simplest form, a negative feedback system consists of a hormone inducing a response in a target cell
, and the response in turn inhibiting further release of the hormone.
(6,7) These agents target the intracellular domain of the tyrosine kinase receptor within the cytoplasm of the target cell
and compete with ATP to bind on the kinase domain.
The K-562 target cells
were washed twice in complete Dubelco modified Eagle medium (DMEM) medium (DMEM supplemented with 2 mM L-glutamine, 1 mM sodium pyruvate, 0.1 mM minimal nonessential amino acids, 5 units/mL penicillin, 50 mg/mL streptomycin (media and supplements from Gibco Laboratories Life Technologies Inc., Grand Island, New York) and 10% fetal calf serum (HyClone Laboratories Inc.
Chemists and materials scientists have been creating virus-size structures to temporarily encase and protect genetic material, diffuse nimbly through three-dimensional tissue, zero in on target cells
, enter those cells, and then release genetic cargoes at the proper locations.
The "corrected" gene undergoing transfer into the affected cell is called a "transgene." A transgene requires delivery into the affected individual's body to reach the target cells
. Transgene delivery into target cells
requires a carrier or a vector.
Anderson's view, this should come only after animal research had demonstrated some key points: that the new gene could be put into the intended target cells
and would remain there capable of functioning that the body would regulate the transplanted gene appropriately and that it would not harm the cell.
Stefano Pluchino from the Cambridge Stem Cell Institute said the tiny vesicles in stem cells contain molecules like proteins and nucleic acids that stimulate the target cells
and help them to survive: they act like mini "first aid kits".
"It allows almost any protein to diffuse into a target cell
. A few hundred molecules of perforin is sufficient to obliterate any cell."
The resulting fusion protein may be used to deliver the biologically active ligand to a specific target cell