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  1. May 2019
    1. A synthetic peptide (KMMTSKDNLNIDIPS) based on the PfCDPK4 sequence was custom synthesized (Peptron Inc.) and conjugated to keyhole limpet hemocyanin via an additional N terminus cysteine residue. It was used to raise polyclonal antisera against PfCDPK4 in rabbit. First immunization was performed using 1 00 ~g of peptide diluted in PBS and mixed 1: 1 v/v with Complete Freund's Adjuvant (CF A). Subsequently, three booster doses of 50 ~g each were given on the 14th, 28t\ 42nd day post first immunization. Blood was collected from animais on 7th, 21 S\ 35th, 49th day. Antibody titers were checked by ELISA using recombinant proteins or ovalbumin conjugated peptides as an antigen. In all cases, pre immune sera from the same rabbit were used as control
    2. Generation of anti-PfCDPK4 antisera
    1. were represented as arbitrary fluorescence units and comparisons were made against the untrea!ed control samples. Exogenous addition of hydrogen peroxide to cells was used as a positive control for the assay
    2. he generation of reactive oxygen species in macrophages was detected by fluorimetry using the fluorescent dye CM-H2DCFDA, which can detect hydrogen peroxide, hydroxyl radical, peroxyl radical, and peroxynitrite anion (5, 6). To perform the assay, THP-1 macrophages were washed and resuspended in serum and phenol-red free RPMI-1640 medium and incubated at room temperature for 30 min in the presence of CM-H2DCFDA at a final concentration of 1 JiM. Subsequently the cells were washed once with fresh media to remove the excess probe and fluorescence measurements were commenced on a spectrofluorimeter (BMG Fluostar Optima) at an excitation of 480 nm and an emission of 520 nm. Appropriate treatments were initiated and time-kinetic measurements were carried out and the values obtained
    3. Detection of intracellular reactive oxygen species generation
    1. 1.2% acetylphenylhydrazine (APH) solution to render it anemic. The APH solution wa5 prepared in sterile water and pH was neutralized to 7.0 with 1 M HEPES buffer (pH 7.5). The rabbit was allowed to recover for 5 days, after which it was bled. The blood was collected in a sterile tube, containing an equal volume of prechilled salt solution and the mixture was filtered through a cheese cJoth. Filtrate was centrifuged at 2000 g for 10 min. at 4 °C. Supernatant was discarded, the pellet was washed twice with salt solution without heparin and finally, resuspended in equal volume of chilled sterile water. It was kept on ice for a minute and centrifuged at 20,000 g for 20 min. at 4 °C. The supernatant, containing the lysate, was immediately stored in liquid Nitrogen in 0.5 ml aliquots.
    2. The rabbit reticulocyte lysate was prepared as described by Sambrook et al ( 1989). A young male NZW rabbit weighing 2-2.5 Kg was subcutaneously injected for five consecutive days respectively with 2 ml, 1.6 ml, 1.2 ml, 1.6 ml and 2.0 ml of
    3. Preparation of rabbit reticulocyte lysate
    1. with glutamine. Rat-2 and FWIL cells were cultured in IMDM supplemented with glutamine. All media were supplemented with 10 % fetal calf serum~ The cells were maintained in a 5 % co2 atmosphere and were split after 72 hours in culture, at a ratio of 1 : 15 approximately. For splitting the adherent cells, the cells were washed once with HBSS and 0.1 % trypsin in PBS added to the cells. The flask was shaken briefly to ensure a uniform distribution of trypsin over the cells. The cells were incubated in trypsin for 1 - 2 minutes after which 2 ml of FCS was added to the cells to inactivate the trypsin. The trypsin was carefully aspirated from the flask and fresh culture medium was added into the flask. The cells were dislodged from the bottom of the flask by gently tapping the flask against the working bench. Alternately, the cells were resuspended by vigorous pipetting up and down of the medium. The cells were centrifuged at 1500g for 5 minutes at room temperature and the supernate was discarded aseptically. The cells were resuspended in a known volume of fresh culture medium, an aliquot counted on a haemocytometer, and then accordingly seeded at the desired density in a fresh flask. For long term storage, the cells were frozen in a mixture of 95 ~ 0 culture medium and 5 ~ 0 DMSO in liquid nitrogen.
    2. eHO-Kl cells were cultured in Ham s F-12 med1a. NIH3T3, mouse LMtk-and HeLa cells were cultured in DMEM supplemented
    3. Growth and maintenance of cell lines.
    1. weight) as a general anesthetic and ovaries were snap frozen in liquid nitrogen. Ovarian sections of 5 J.lm thickness were cut in a cryostat at -20°C and fixed in chilled methanol for 15 min at RT. Sections passing through follicles were selected, washed with 50 mM PBS and blocked with 3% normal goat serum (NGS) in PBS (v/v) at RT for 1 h. Sections were then washed two times with PBS and incubated with 1: 1 0 dilution of immune serum samples. Ovarian sections incubated with 1:10 dilution of mouse preimmune or immune sera from mice immunized with VR1020 vector served as negative controls. After incubation, the sections were washed three times with PBS and incubated with 1:800 dilution of goat anti-mouse IgG conjugated to FITC (Sigma) for 1 hat RT. The slides were washed three times with PBS, mounted in glycerol : PBS (9 : 1 ), and examined under fluorescence microscope (Optiphot, Nikon, Japan).
    2. Ability of mouse polyclonal antibodies, generated subsequent to immunization with VRbmZP1 and VRdZP3 plasmid DNA, to recognize native ZP was evaluated by indirect immunofluorescence assay. A normal cycling female bonnet monkey and a female dog were ovariectomized after administration of ketamine hydrochloride (5 mg/kg body
    1. Bloodsampleswereobtainedbycuttingthecaudalpeduncleandanalysedforlacticacidusinganenzymatictechnique(SigmaCo,1974)MeasurementsweremadeinQuartzcuvettesat340nmwithaBeckmanAVSpectrophotometer.Standardcurvesweremadeonthedaythebloodlacticaciddeterminationsweremade.
    2. Bloodlacticacid
    1. ubjected to three washes with PBST and two washes with PBS. The blot was developed using the substrate DAB (Sigma, U.S.A.) or with ECL (Amersham Biosciences, U.K.)
    2. he protein samples were diluted with 4X sample buffer which is essentially SDS-reducing buffer (O.SM Tris-Cl, pH 6.8, Glycerol, 10% (w /v) SDS, 2-J3-mercaptoethanol, 0.05% (w /v) bromophenol blue). The samples were denatured at 1000C for 10 min and the proteins were resolved on 12-15% SDS-polyacrylamide gel at 25-30mA. For detection, the proteins were transferred on to nitrocellulose (NC) membrane (Hybond-C extra, Amersham, U.K.) at 200mA, for either 1 hr or at 12 rnA, 40C for overnight. After the transfer was over, the NC membrane was washed thrice with PBST (1X PBS with 0.1% Tween 20) and blocked with 2% BSA for 2hrs (in PBST) at room temperature. Primary antibody to HBx/Vif/ APOBEC3G-NT raised in rabbit and were diluted to 1:1,000 in PBST. One hour incubation with the primary antibody was followed by three washes with PBST (10 min each) and then 1 hr incubation with 1:1,000 dilution of the secondary antibody (Anti-rabbit IgG (Fe) HRP conjugate) was carried out. The blot was further
    3. Westem blot analysis
    1. 30nm corresponds only to the intermediate. Since equal number of cells was taken for estimation, the height of the peak was taken as a measure of the ergosterol content
    2. Ergosterol content was measured as described by Arthington-Skaggs et al. (1999) with slight modifications. Briefly, equal number of cells were harvested and washed with PBS to remove media and FBS. They were resuspended in 3mL of 25% alcoholic KOH (25g KOH, 35mL sterile distilled water brought to lOOmL with ethanol) and vortexed for one minute. The cell suspension was transferred to a glass vial and incubated at 85°C for 1 hr. The vial was cooled to room temperature followed by the addition of 1mL sterile distilled water and 3mL of n-heptane. The vial was vortexed for 3 mins after which the heptane layer was collected. It was diluted 5 times in absolute ethanol and transferred to a cuvette. A spectrum was recorded between 220nm and 300nm. The peak at 281.5nm corresponds to ergosterol along with some intermediates.
    3. Spectrophotometric estimation of ergosterol
    4. Plasmid DNA was isolated at small scale using QIAprep Miniprep kit according to manufacturer's protocol. Briefly, 5mL of overnight E. coli culture was pelleted and resuspended in 250J..LL Buffer P1(50mM Tris-Cl, pH8.0; 10mM EDTA and 100p.g/mL RNase A). To this, 250 J..LL of Buffer P2(200mM NaOH and 1 %w /v NaOH) was added and mixed thoroughly by inverting the tube 4-6 times. 350 IlL of Buffer N3 (proprietary) was added and mixed immediately and thoroughly by inverting the tube 4-6 times. This was followed by centrifugation at 13000 x g for 10min at RT. The supernatant was applied to a QIAspin column and centrifuges at 13000 x g for 30-60s. The column was washed with 0.5mL Buffer PB followed by 0.75 mL Buffer PE. Residual wash buffer was removed by centrifugation for an additional 60s. The plasmid DNA bound to the column was eluted using the elution buffer, Buffer EB (10mM Tris-Cl, pH 8.5) provided with the kit, or alternatively with nuclease-free water. The concentration of the obtained DNA was estimated by measuring the absorbance at 260nm (A26o) and using the known formula: DNA concentration= A260 X SOX dilution factor
    5. Miniprep to isolate plasmids