Anti-FITC polyclonal antibody [HRP]

Purpose: Membrane engineering has versatile applications in adoptive cell therapies, immune therapy or drug delivery. Incorporation of lipidated antibody-derived ligands into cells may enforce supraphysiological cell interactions that offer new therapeutic approaches. A challenge is the defined synthesis of lipidated ligands that effectively interact with such membranes. Methods: Sortase-A was used to attach a PEGylated, dimyristyl lipid-anchor on single-domain antibodies (VHH). The membrane insertion was investigated on liposomal bilayers, myeloid-derived suppressor cells (MDSC) and T cells. Results: The lipidated VHHs remodeled liposomal as well as cellular membranes. The VHH carrying liposomes were successfully targeted towards antigen-positive cells. MDSC and T cells were both modified with lipidated VHHs as detected with an FITC-anti-llama antibody. T cells that carried an anti-CD11b VHH showed cellular association in vitro with CD11b(+)Gr-1(+) MDSC in a two-dimensional magnetic activated cell sorting / flow-cytometry assay. Conclusion: The applied combination of chemoenzymatic ligation, PEGylated lipid anchors and single-domain antibodies delivers water-soluble and chemically defined lipidated ligands, which readily associate with liposomal and cellular membranes. This enables liposomal drug targeting and artificial cell-cell interactions. Hence, the presented concept for lipidation of single-domain antibodies is promising for further application in the field of drug delivery or cell-based therapies.

Background: Gliomas are commonly diagnosed tumors in the central nervous system that have an elevated mortality rate. The present study evaluated pyrazolo[4,3-c]pyridine-4-one (PP-4-one) as an anti-proliferative agent against glioma cells and investigated the associated mechanism. Material/Methods: The changes in cell growth were analyzed by Cell Counting Kit-8 (CCK-8) and apoptosis by flow cytometry using Annexin V-FITC staining kit. The FACSCalibur flow cytometer was used for analysis of DNA content and western blotting for protein expression. Results: The PP-4-one treatment suppressed viability of U251, C6, and U87 cells significantly at a concentration of 0.25 mu M. At a concentration of 16 mu M, PP-4-one treatment for 72 hours suppressed viability of U251, C6, and U87 cells to 24%, 21%, and 20%, respectively. Treatment with PP-4-one suppressed cyclic 3',5'-adenosine monophosphate (CAMP) levels in U251 and C6 cells significantly (P<0.05) depending on the concentration. The apoptotic cells were increased significantly (P<0.05) by PP-4-one treatment in U251 and C6 cell cultures. A considerable enhancement in the proportion of U251 and C6 cells in the G0/G1 phase was recorded on incubation with PP-4-one. Treatment of U251 and C6 cells with PP-4-one markedly enhanced p21 expression relative to the control. The B-cell lymphoma (Bcl-2) level in PP-4-one treated U251 and C6 cells was markedly lower relative to the control cells. The Bax, caspase-3, and caspase-9 levels were elevated markedly by PP-4-one treatment in U251 and C6 cells. Conclusions: This study demonstrated that PP 4-one has anti-proliferative potential for glioma cells via targeting cAMP and Bcl-2 levels. It also promoted glioma cell apoptosis through caspase activation and arrest of the cell cycle. Thus, PP-4-one may be used to develop drug candidates for the glioma treatment.