Effect of paclitaxel-loaded nanoparticles on the viability of human hepatocellular carcinoma HepG2 cells.

OBJECTIVE: To explore effects of paclitaxel-loaded poly lactic-co-glycolic acid (PLGA) particles on the viability of human hepatocellular carcinoma (HCC) HepG2 cells. MATERIALS AND METHODS: The viability of HepG2 cells was assessed using MTT under different concentrations of prepared paclitaxel-loaded particles and paclitaxel (6.25, 12.5, 25, 50, and 100 mg/L), and apoptosis was analyzed using Hochest33342/Annexin V-FITC/PI combined with an IN Cell Analyzer 2000. RESULTS: Paxlitaxel-loaded nanoparticles were characterized by narrow particle size distribution (158.6 nm average particle size). The survival rate of HepG2 cells exposed to paclitaxel-loaded PLGA particles decreased with the increase of concentration and time period (P<0.01 or P<0.05), the dose- and time-dependence indicating sustained release (P<0.05). Moreover, apoptosis of HepG2 cells was induced, again with an obvious dose- and time-effect relationship (P<0.05). CONCLUSIONS: Paclitaxel-loaded PLGA particles can inhibit the proliferation and induce the apoptosis of HCC HepG2 cells. This new-type of paclitaxel carrier body is easily made and has low cost, good nanoparticle characterization and sustained release. Hence, paclitaxel- loaded PLGA particles deserve to be widely popularized in the clinic.

Transcellular transport characteristics of huperzine alone or in combination with ginkgolide B across Caco-2 and Madin-Darby canine kidney cell monolayer.

OBJECTIVE: To study the various processes involved in transcellular transport (TT) of huperzine A alone or in combination with ginkgolide B in Caco-2 and Madin-Darby canine renal (MDCK) cell monolayer. METHODS: The transepithelial passage was assayed in the apical-to-basolateral (AP to BL) direction and opposite direction (BL to AP) in both cell lines. The determination of huperzine A and ginkgolide B were performed by high performance liquid chromatography (HPLC). The passage rates of huperzine A and ginkgolide B were calculated. Bi-directional TT (absorption and secretion) were taken in huperzine A and ginkgolide B in Caco-2 and MDCK cell monolayer. RESULTS: TT absorption and secretion kinetics of huperzine A and ginkgolide B across two cells existed at the same time. The passage rates of huperzine A were increased significantly with adding different concentrations of ginkgolide B. CONCLUSIONS: The compound preparations of HA in combination with GB for dementia caused by cerebral ischemic have synergistic effects on the pharmacodynamics, and improve the bioavailability through BBB.

[Preparation of monoclonal antibody against human c-erbB2 and identification of its specificity].

AIM: To prepare monoclonal antibody(mAb) against human c-erbB2 and identify its specificity. METHODS: The epitope of human c-erbB2 antigen was analyzed by using computer software and a immunodominant epitope at the carboxyl-terminal was selected. A peptide consisting of 13 amino acids was synthesized and coupled with keyholelimpet hemocyanin (KLH), and then it was used to immunize BLAB/c mice. The splenocytes of the immunized mice were fused with Sp2/0 cells routinely and the hybridoma cells were selected by HAT selected culture, indirect ELISA, and immunohistochemical staining, and cloned by limiting dilution. The specificity of the mAb was identified by cross-reaction test and blocking test. RESULTS: A hybridoma cell line SC8C1, stably secreting anti-c-erbB2 mAb was obtained. The mAb SC8C1 could react to breast cancer tissue expressing c-erbB2 molecule but did not react to other c-erbB2-negative cells. The mAb will lose the activity after being blocked with synthesized 13 peptide. CONCLUSION: A anti-c-erbB2 mAb SC8C1 is prepared successfully using synthesized 13 peptide as immunogen.