Electroporator. monoclonal antibodies against cell surface proteins in rats. electroporation , GroEL, Hyaluronidase Background Membrane proteins such Pseudouridine as cytokine receptors and G protein-coupled receptors have been regarded as medicinal drug targets, and generation of antibodies reactive with the native form of such membrane proteins would lead to antibody-drug development. However, most antibodies generated so far by immunization with a recombinant protein produced in react only with the immunizing recombinant proteins, but not with the native proteins on cell surfaces. The same problems have often been experienced with immunization with peptides as antigens. In order to generate mAbs which could recognize the native proteins, we have developed the original DNA-immunization method in which plasmid DNA is directly transferred into mouse skeletal muscle utilizing GroEL, is a molecular chaperone that is responsible for the transportation and refolding of proteins and GroEL fusion proteins are highly expressed in the soluble fraction ( Furutani GroEL also acts as an adjuvant via TLR4 ( Fujimoto provides adjuvant effects via Pseudouridine TLR2 and TLR4 ( Scheibner cDNA (pMXs-IL9R-IRES-hNGFR) or an empty vector (EV; pMXs-IRES-hNGFR). The B300-19 cell line was provided by Dr. Takashi Nakayama. The retroviral vectors and B300-19 transfectants generated by us will be available upon request. Plat-E cells The Plat-E cell line and an original pMXs vector were provided by Dr. Toshio Kitamura. Lew/SSN rats (Female Lew/SSN rats were purchased from Sankyo Lab Service. Rats were immunized at 4 weeks of age) Depilatory cream (general commercialized product) Sodium pentobarbital (Kyoritsu Seiyaku, Somnopentyl Injection) QIAGEN Plasmid Giga Kit (QIAGEN, catalog number: 12191) Fugene HD (Promega, catalog number: E2311) FITC-conjugated secondary antibodies [FITC-conjugated goat anti-rat IgG (H+L)] (SouthernBiotech, catalog number: 3050) FITC-anti-IgG1 (BD Bioscience, catalog number: 562580) PE-anti-CD138 (Biolegend, catalog number: 142503) PE-anti-IgM (Thermo, catalog number: 12-5790-81) PE-anti-IgD (Biolegend, catalog number: 405705) PerCP/Cy5.5-anti-T and -B Cell activation antigen clone GL-7 (Biolegend, catalog number: 144609) PE/Cy7-anti-CD38 (Thermo, catalog number: 25-0381-80) APC/Cy7-anti-B220 (Biolegend, catalog number: 103223) Biotin-NP14-BSA (in house) Brilliant Violet 421 Streptavidin (Biolegend, catalog number: Pseudouridine 405226) MEM medium (Thermo, catalog number: 11095080) Hyaluronidase (Sigma, catalog number: H3631-30KU) 70% (v/v) ethanol phosphate buffered saline (pH 7.4) Tris EDTA Sodium azide Hyaluronidase solution Pseudouridine (see Recipes) Tris-EDTA buffer (see Recipes) FACS Buffer (see Recipes) Plasmid DNA solution (see Recipes) Equipment Electroporator (BTX, Electro Square Porator ECM830, Figure 1A) Open in a separate window Figure 1. Details of the experimental equipment for DNA immunization.A. Electroporator. B. Electrodes and copper cables with IC hook. C. 1 ml syringe with a 26 G two-stage needle. D. 26 G two-stage needle. Copper cables with IC hook (Toyoshima, made-to-order or general commercialized product, length: more than one meter, Figure 1A-1B) 26 G two-stage needle (Toyoshima, made-to-order, Figure 1C-1D) Gamma irradiation device (Atomic Energy of Canada Limited, Gammacell 40) BD FACS Calibur BD FACS CantoII Software FlowJo (Tree Star, https://www.flowjo.com) Procedure Prepare and set up the electroporator (Figure 1A): Voltage: 100 V Pulse length: 50 ms Pulse number: 6 (1 s interval) Periodicity: 1 kHz. Anesthetize rat with 24-36 mg/kg sodium pentobarbital. (Duration time: 30-60 min) Depilate hindlimbs with depilatory cream (cream should stay for about 3 min) (Figure 2A). Open in a separate window Figure 2. Experimental procedure of DNA immunization using electroporation. A. Depilate hindlimbs. B. Inject hyaluronidase solution into quadriceps muscle and leave to stand for 10 min. C. Stab the electrodes into the quadriceps muscle. D. Inject plasmid DNA Pseudouridine solution CDH1 into the same place where hyaluronidase solution pretreatment was done. Subsequently, pulse by electroporator. Repeat the same operation (A-D) to the other hindlimb. Sterilize hindlimbs using absorbent cotton impregnated with 70% (v/v) ethanol. Inject 50 l of hyaluronidase solution into the quadriceps muscle using a 1 ml syringe with a 26 G two-stage needle (Figure 2B). Leave to stand for 10 min. Stab electrodes into the quadriceps muscle (Figures 1B and ?and2C2C). Inject 30 l of plasmid DNA solution into the same place where hyaluronidase solution pretreatment was done (Figure 2D). Pulse by electroporator (100 V, 50 ms pulse length, 1 kHz, 6 times with each.