Neuroscience-Best Transfection Practices

I have multiple posting of customer success in transfecting siRNA and plasmids into neurons using Neuromics' i-Fect^TM and pn-Fect^TM...related publications.

Here I post excellent data, images and testimonials provided by researchers using our Magnetic Assisted Transfection (MATraTM). Our goal is to continue our journey towards having the best practices for gene expression analysis studies in the CNS.

With Magnet Assisted Transfection,  IBA/Neuromics offers a very gentle and potent tool for the transfection of many kinds of neuronal cells. Magnet Assisted Transfection is the ideal solution to overcome problems related to the study of complex and easily interrupted systems. Transfection of primary cortical neurons Example 1  Embryonic cortical neurons were transfected with human NCAM. Embryonic cortical neurons were transfected with human NCAM. After transfection membrane-localized NCAM (not endocytosed) was detected using a Cy3-coupled secondary antibody (red). Afterwards, the internalised, endocytosed NCAM was stained by a Cy2-coupled secondary antibody (green, see arrows) in the cell soma (left) and in axonal vesicles (right). Example 2 pPrimary cortical neurons from mice embryonic day 15.5 (E15.5) were grown on poly-L-lysine coated coverslips at a density of 800.000 cells/well in a 24-well plate. The neurons were transfected after 1 day in vitro (DIV 1) with pCX-EGFP-N1 plasmid Primary cortical neurons from mice embryonic day 15.5 (E15.5) were grown on poly-L-lysine coated coverslips at a density of 800.000 cells/well in a 24-well plate. The neurons were transfected after 1 day in vitro (DIV 1) with pCX-EGFP-N1 plasmid. Transfection was carried out as recommended by the manufacturer (0.6 µg DNA, 0.6 µL Matra-A reagent). Cells were fixed 24 h later (DIV 2) and GFP fluorescence was visualized using a confocal laser scanning microscope. "With MATra we achieved a higher transfection efficiency than with different liposomal transfection methods and no toxicity to the cells was observed." Dr. Simone Diestel, Institute of Animal Science, University Bonn, Germany Cerebellar granular cells from CD1 mice  Cultured cerebellar granular cells from CD1 mice were transfected by below 4 constructs Cultured cerebellar granular cells from CD1 mice were transfected by below 4 constructs (A-D) using MATra-A. (A) MyrPalm-mCFP, cyan (provided by Dr. R. Tsien, UCLA) (B) Actin-DsRed, red (C) Flotillin-2-mVenus, yellow (B and C provided by Dr. R. Tikkanen, University of Giessen) (D) Battenin-myc, detected by using GAM-Alexa647, dark green (E) Surface: Crop of the whole image with 3D surface rendered fluorescence signals overlayed on phase contrast image. (F) PhaCo: Phase contrast image Primary hippocampal neurons (E14)

 Primary hippocampal neurons (E14) were grown on 15 mm glass coverslips on a 12 well at density of 150.000/cm². The neurons were transfected 4 d.i.v. with pSyn-eGFP  Primary hippocampal neurons (E14) were grown on 15 mm glass coverslips on a 12 well at density of 150.000/cm². The neurons were transfected 4 d.i.v. with pSyn-eGFP using 25 µl MATra complex per well (prepared by adding a MATra-A Reagent-DNA complex mixture (2.8 µg cDNA; 2.8 µl beads) into 175 µl neuronal medium without serum). The cells were fixed 6 d.i.v. with 4% PFA and imaged "With MATra we can transfect and modulate the expression levels of exogenous proteins in highly sensitive primary neurons without any toxicity. Once optimized, double and even triple transfections with different DNA ratios are easily achieved", said Dr. Mika Ruonala, Center for Membrane Proteomics, University of Frankfurt. Neurosciences are a vast and expanding field of research focussing on highly sophisticated and enthralling questions. With Magnet Assisted Transfection IBA/Neuromics offers a very gentle and potent tool for the transfection of many kinds of neuronal cells. Magnet Assisted Transfection is the ideal solution to overcome problems related to the study of complex and easily interrupted systems.

Delivering TRPV1 shRNA to DRG of T8-L3 Segments of the Spinal Cord

I have reported use of our i-FectTM siRNA delivery kit for gene expression analysis studies of DOR, hTERT, The β3 subunit of the Na+,K+-ATPase, rSNSR1, NTS1. NAV1.8, Survivin, Flaviviruses and more.

This is the first publication referencing the use of i-Fect to delivery shRNA intrathecally. In this study, researchers knockdown TRPV1 Channels in DRGs to study their role in regulation of blood pressure.

Shuang-Quan Yu, Donna H. Wang. Intrathecal injection of TRPV1 shRNA leads to increases in blood pressure in rats. DOI: 10.1111/j.1748-1716.2011.02285.x. Copyright © 2011 Scandinavian Physiological Society.

Aim: The transient receptor potential vanilloid type 1 (TRPV1) channels have been implicated to play a role in blood pressure regulation. However, contribution of tissue specific TRPV1 to blood pressure regulation is largely unknown. Here we test the hypothesis that TRPV1 expressed in dorsal root ganglia (DRG) of lower thoracic and upper lumbar segments (T8-L3) of the spinal cord and their central and peripheral terminals constitutes a counter regulatory mechanism preventing the increases in blood pressure.

Methods: TRPV1 was knocked down by intrathecal injection of TRPV1 shRNA in rats. Systolic blood pressure and mean arterial pressure (MAP) were recorded. The level of TRPV1 and tyrosine hydroxylase was measured by Western blot.

Results: Intrathecal injection of TRPV1 shRNA (6 μg kg−1 per day) for 3 days increased systolic blood pressure and MAP when compared to rats that received control shRNA (control shRNA: 112±2 vs TRPV1 shRNA: 123±2 mmHg). TRPV1 expression was suppressed in T8-L3 segments of dorsal horn and DRG as well as mesenteric arteries of rats given TRPV1 shRNA. Contents of tyrosine hydroxylase, a marker of sympathetic nerves, were increased in mesenteric arteries of rats treated with TRPV1 shRNA. Pretreatment with the 1-adrenoceptor blocker, prazosin (1 mg/kg/day, p.o.), abolished the TRPV1 shRNA-induced pressor effects.

Conclusion: Our data show that selective knockdown of TRPV1 expressed in DRG of T8-L3 segments of the spinal cord and their central and peripheral terminals increases blood pressure, suggesting that neuronal TRPV1 in these segments possesses a tonic anti-hypertensive effect possibly via suppression of the sympathetic nerve activity.