[Preparation and application of rabbit polyclonal antibody against human lactate dehydrogenase C4(LDHC4)].

Objective To prepare rabbit polyclonal antibody specifically against human lactate dehydrogenase C4 (LDHC4). Methods Site-directed mutation was performed by PCR to generate the mutated LDHC gene, and the mutated gene was ligated into the pET-28a vector to form the pET-28a-LDHC recombinant expression vector. The recombinant vector was introduced into E. coli BL21 (DE3), and LDHC4 protein was obtained by induced expression. The recombinant protein was used as an antigen to immunize New Zealand rabbits, and the antiserum was obtained after three boosted immunizations. The titer of the antiserum against LDHC4 were detected by ELISA. Western blot was used to detect the specificity of the antiserum, and immunohistochemistry was used to detect the expression of LDHC4 in human triple-negative breast cancer tissue. Results A specific rabbit anti-human LDHC4 polyclonal antibody was obtained with an antibody titer of 1:51 200. The antibody can be used for Western blot and immunohistochemistry. Conclusion The specific rabbit anti-human LDHC4 polyclonal antibody is successfully prepared.

A Novel Paclitaxel-Loaded Polymeric Micelle System with Favorable Biocompatibility and Superior Antitumor Activity.

BACKGROUND/AIM: Polymeric micelles are promising vehicles for paclitaxel delivery. Further improvement in the stability of the micelle formulation is desirable. MATERIALS AND METHODS: Monomethoxy poly(ethylene glycol)-block-poly(D,L-lactide)-9-fluorenylmethoxycarbonyl-L-phenylalanine (mPEG-PDLLA-Phe(Fmoc)) was synthesized through a classical esterification reaction. Paclitaxel-loaded mPEG-PDLLA-Phe(Fmoc) micelles (PTX-PheMs) were prepared by the self-assembly method. Composition, structure and physicochemical properties were characterized. Pharmacokinetics were evaluated in rats. Therapeutic effect was evaluated in tumor-bearing mice. Safety profile was assessed by a hemolysis assay and an acute-toxicity study. RESULTS: The average size of PTX-PheMs was about 45 nm. The hemolysis and acute-toxicity tests confirmed its biocompatibility and safety. The pharmacokinetics and therapeutic effect experiments demonstrated its long circulation property and superior antitumor effect. CONCLUSION: mPEG-PDLLA-Phe(Fmoc) micelle is a biocompatible and effective drug delivery system for hydrophobic drugs such as PTX.

Myosin Vb controls biogenesis of post-Golgi Rab10 carriers during axon development.

Polarized membrane addition is crucial for axon development and elongation during neuronal morphogenesis. This process is believed to be regulated by directed membrane trafficking of Rab10-containing post-Golgi carriers. However, the mechanisms underlying the biogenesis of these carriers remain unclear. Here, we report that Rab10 interaction with myosin Vb (MYO5B) determines the formation of Rab10 carriers and is important for axon development. Rab10 interacts with the exon D-encoded domain of MYO5B. Downregulating the expression of MYO5B (+D) or blocking its interaction with Rab10 impairs the fission of Rab10 vesicles from trans-Golgi membranes, causes a decrease in the number of Rab10 transport carriers and inhibits axon development in cultured hippocampal neurons. Furthermore, the MYO5B-Rab10 system is required for axon development of vertebrate neocortical neurons or zebrafish retinal ganglion cells in vivo. Thus, specific interaction between Rab10 and MYO5B controls the formation of Rab10 vesicles, which is required for axon development.

Lgl1 activation of rab10 promotes axonal membrane trafficking underlying neuronal polarization.

Directed membrane trafficking is believed to be crucial for axon development during neuronal morphogenesis. However, the underlying mechanisms are poorly understood. Here, we report a role of Lgl1, the mammalian homolog of Drosophila tumor suppressor Lethal giant larvae, in controlling membrane trafficking underlying axonal growth. We find that Lgl1 is associated with plasmalemmal precursor vesicles and enriched in developing axons. Lgl1 upregulation promoted axonal growth, whereas downregulation attenuated it as well as directional membrane insertion. Interestingly, Lgl1 interacted with and activated Rab10, a small GTPase that mediates membrane protein trafficking, by releasing GDP dissociation inhibitor (GDI) from Rab10. Furthermore, Rab10 lies downstream of Lgl1 in axon development and directional membrane insertion. Finally, both Lgl1 and Rab10 are required for neocortical neuronal polarization in vivo. Thus, the Lgl1 regulation of Rab10 stimulates the trafficking of membrane precursor vesicles, whose fusion with the plasmalemma is crucial for axonal growth.