Stimulated trans-acting factor of 50 kDa (Staf50) inhibits HIV-1 replication in human monocyte-derived macrophages.

In order to identify cellular genes which interfere with HIV-1 replication in monocyte-derived macrophages (MAC), cells were stimulated with interferon (IFN) or lipopolysaccharide (LPS) leading to a pronounced inhibition of HIV-1 infection in these cells, and the resulting gene expression was analyzed. Using the microarray technology we identified a gene named Stimulated Trans-Acting Factor of 50 kDa (Staf50), which is known to repress the activity of the HIV-1 LTR. Analysis of the Staf50 expression by real-time PCR showed an overexpression in IFNalpha (up to 20-fold) and LPS (up to 10-fold)-stimulated MAC as well as in infected cells (up to 3-fold).

Selective targeting of antibody-conjugated nanoparticles to leukemic cells and primary T-lymphocytes.

In the present study, surface-modified nanoparticles based on biodegradable material were used for antibody coupling in order to get a selective drug carrier systems. Gelatin nanoparticles were prepared by a desolvation process. Sulfhydryl groups were introduced which enabled the linkage of NeutrAvidin (NAv).

Preparation and characterisation of antibody modified gelatin nanoparticles as drug carrier system for uptake in lymphocytes.

Established methods of protein chemistry can be used for the effective attachment of drug targeting ligands to the surface of protein-based nanoparticles. In the present work gelatin nanoparticles were used for the attachment of biotinylated anti-CD3 antibodies by avidin-biotin-complex formation. These antibody modified nanoparticles represent a promising carrier system for the specific drug targeting to T-lymphocytes.

Intracellular tracking of protamine/antisense oligonucleotide nanoparticles and their inhibitory effect on HIV-1 transactivation.

Membrane transport of antisense oligonucleotides (ODN) is an inefficient process which requires special carriers for their intracellular delivery. We have developed a delivery system for AS-ODN and their phosphorothioate analogues (AS-PTO) directed against human immunodeficiency virus type 1 (HIV-1) tat mRNA for efficient transfection of HIV-1 target cells. Protamine was used to complex AS-ODN and AS-PTO to form nanoparticles with diameters of about 180 nm and surface charges in the range of -18 to +30 mV.