JOAO EZEQUIEL DE OLIVEIRA

JOAO EZEQUIEL DE OLIVEIRA

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Periplasmic synthesis and purification of the human prolactin antagonist Δ1‑11‑G129R‑hPRL
2021 - SUZUKI, MIRIAM F.; ALMEIDA, LARISSA A.; POMIN, STEPHANIE A.; SILVA, FELIPE D.; FREIRE, RENAN P.; OLIVEIRA, JOAO E.; AFFONSO, REGINA; SOARES, CARLOS R.J.; BARTOLINI, PAOLO
The human prolactin antagonist Δ1-11-G129R-hPRL is a 21.9 kDa recombinant protein with 188 amino acids that downregulates the proliferation of a variety of cells expressing prolactin receptors. Periplasmic expression of recombinant proteins in E. coli has been considered an option for obtaining a soluble and correctly folded protein, as an alternative to cytoplasmic production. The aim of this work was, therefore, to synthesize for the first time, the Δ1-11-G129R-hPRL antagonist, testing different activation temperatures and purifying it by classical chromatographic techniques. E. coli BL21(DE3) strain was transformed with a plasmid based on the pET25b( +) vector, DsbA signal sequence and the antagonist cDNA sequence. Different doses of IPTG were added, activating under different temperatures, and extracting the periplasmic fluid via osmotic shock. The best conditions were achieved by activating at 35 °C for 5 h using 0.4 mM IPTG, which gave a specific expression of 0.157 ± 0.015 μg/mL/A600 at a final optical density of 3.43 ± 0.13 A600. Purification was carried out by nickel-affinity chromatography followed by size-exclusion chromatography, quantification being performed via high-performance size-exclusion chromatography (HPSEC). The prolactin antagonist was characterized by SDS-PAGE, Western blotting, reversed-phase high-performance liquid chromatography (RP-HPLC) and MALDI-TOF–MS. The final product presented > 95% purity and its antagonistic effects were evaluated in vitro in view of potential clinical applications, including inhibition of the proliferation of cancer cells overexpressing the prolactin receptor and specific antidiabetic properties, taking also advantage of the fact that this antagonist was obtained in a soluble and correctly folded form and without an initial methionine.
Expression of glycosylated human prolactin in HEK293 cells and related N‑glycan composition analysis
2019 - SILVA, FELIPE D.; OLIVEIRA, JOÃO E.; FREIRE, RENAN P.; SUZUKI, MIRIAM F.; SOARES, CARLOS R.; BARTOLINI, PAOLO
Prolactin (PRL) is a hormone produced by the pituitary gland with innumerable functions, such as lactation, reproduction, osmotic and immune regulation. The present work describes the synthesis of hPRL in human embryonic kidney (HEK293) cells, transiently transfected with the pcDNA-3.4-TOPO® vector carrying the hPRL cDNA. A concentration of ~ 20 mg/L, including glycosylated (G-hPRL) and non-glycosylated (NG-hPRL) human prolactin, was obtained, with ~ 19% of G-hPRL, which is higher than that observed in CHO-derived hPRL (~ 10%) and falling within the wide range of 5–30% reported for pituitary-derived hPRL. N-Glycoprofiling analysis of G-hPRL provided: (i) identification of each N-glycan structure and relative intensity; (ii) average N-glycan mass; (iii) molecular mass of the whole glycoprotein and relative carbohydrate mass fraction; (iv) mass fraction of each monosaccharide. The data obtained were compared to pituitary- and CHO-derived G-hPRL. The whole MM of HEK-derived G-hPRL, determined via MALDI–TOF-MS, was 25,123 Da, which is 0.88% higher than pit- and 0.61% higher than CHO-derived G-hPRL. The main difference with the latter was due to sialylation, which was ~ sevenfold lower, but slightly higher than that observed in native G-hPRL. The “in vitro” bioactivity of HEK-G-hPRL was ~ fourfold lower than that of native G-hPRL, with which it had in common also the number of N-glycan structures.
Transient expression of recombinant human prolactin and thyrotropin in human embryonic kidney (Expi293FTM) suspension cells
2017 - SILVA, F.D.; SEVILHANO, T.C.A.; FREIRE, R.P.; SUZUKI, M.F.; OLIVEIRA, J.E.; PERONI, C.N.; RIBELA, M.T.C.P.; BARTOLINI, P.; SOARES, C.R.J.
Human prolactin (hPRL) and human thyrotropin (hTSH) are pituitary polypeptide hormones with key functions in the physiological regulation of the human body. hPRL is highly secreted during lactation, has important action in reproduction and for immunoregulation, among other functions. hTSH is related to the control of thyroid gland. The Chinese Hamster Ovary (CHO) and Human Embryonic Kidney (HEK293) cells are the most used hosts for expression of recombinant human proteins because they can be easily cultured in suspension conditions, and express high levels of proteins that have a relative similarity in post-translational modifications compared to their human counterparts. Our laboratory has experience in the synthesis of these proteins in the Escherichia coli periplasm (hPRL), adhered CHO (hPRL and hTSH), suspension CHO (hPRL) and adhered HEK293T cells (hTSH). The aim of this work was to produce hPRL and hTSH in suspension Expi293FTM cells for their characterization. The hPRL and hTSH cDNA were introduced into the commercial plasmid pcDNATM 3.4-TOPO® and 30 μg of these plasmids were used to transfect 30 mL of suspension Expi293FTM cells (2.5 x 106 cells/mL) in a 125 mL erlenmeyer, using 81 μL of ExpiFectamineTM transfection agent. After 16 h of transfection, 150 μL of Enhancer 1 and 1.5 mL of Enhancer 2 were added and the culture was maintained in an incubator at 37 °C, 8% CO2, at 125 rpm in orbital shaker. Samples of conditioned media (Expi293TM expression medium) were collected during 4 days and stored at -80 °C. These were analyzed by SDS-PAGE, ELISA, Western blotting, and HPLC. For the first time, hPRL and hTSH, were transiently expressed in human (Expi293FTM) suspension cells, the expression levels reaching, on the 3rd day, 46 μg of hPRL/mL and 116 μg of hTSH/mL. These results show that the expression is clearly dependent on the characteristics of the protein and that this methodology is very efficient to obtain high levels of human glycoproteins in a short time and will allow us to purify them and compare their glycosylation profiles of these to CHO-derived and human native pituitary hormones.
Uncovering the mechanism of action of the anti-diabetic effects of bromocriptine: the role of prolactin
2014 - FURIGO, ISADORA C.; DONATO, JOSE; SUZUKI, MIRIAM F.; ZAMPIERI, THAIS T.; PEDROSO, JOAO A.B.; LOBO, ANGELA M.R.; ALENCAR, AMANDA; OLIVEIRA, JOAO E.; BARTOLINI, PAOLO; SOARES, CARLOS R.J.
N-glycoprofiling analysis in a simple glycoprotein model: glycosylated human prolactin
2014 - CAPONE, MARCOS V.; SUZUKI, MIRIAM F.; OLIVEIRA, JOAO E.; SOARES, CARLOS R.; BARTOLINI, PAOLO
N-glycoprofiling analysis in a single glycoprotein model: a comparison between recombinant and pituitary glycosylated human prolactin
2015 - CAPONE, MARCOS V.N.; SUZUKI, MIRIAM F.; OLIVEIRA, JOAO E.; DAMIANI, RENATA; SOARES, CARLOS R.J.; BARTOLINI, PAOLO
The influence of Escherichia coli cultivation temperature on interferon alpha 2a expression (IFN-'alfa'2a)
2014 - ARTHUSO, FERNANDA dos S.; SUZUKI, MIRIAM F.; OLIVEIRA, NELIO A. de J.; OLIVEIRA, JOAO E. de; BARTOLINI, PAOLO; SOARES, CARLOS R.J.
Expression and characterization of mouse prolactin (mPRL) in CHO dhfr-cells
2014 - SUZUKI, MIRIAM F.; SILVA, ALINE B. da; OLIVEIRA, JOAO E. de; ARTHUSO, FERNANDA dos S.; BARTOLINI, PAOLO; SOARES, CARLOS R.J.
A practical and fast adaptation of CHO cells expressing human prolactin to grow in suspension and its application to laboratory production
2011 - ARTHUSO, F.S.; CAPONE, M.V.N.; SUZUKI, M.F.; SOUSA, J.M.; OLIVEIRA, J.E.; BARTOLINI, P.; SOARES, C.R.J.
Purification and characterization recombinant glycosylated human prolactin synthesized in cho cells
2008 - OLIVEIRA, T.L.; HELLER, S.R.; OLIVEIRA, J.E.; ARTHUSO, F.S.; GOULART, H.R.; SOUSA, J.M.; SUZUKI, M.F.; BARTOLINI, P.; SOARES, C.R.S.