Pilot-Scale Production and Characterization of Paramyosin, a Vaccine Candidate for Schistosomiasis Japonica

ABSTRACT Despite effective chemotherapy, schistosomiasis remains a major public health problem in the developing world, with at least 200 million active infections resulting in significant morbidity. Rapid reinfection after treatment, accompanied by extensive residual morbidity, mandates alternative control strategies, including vaccine development. Paramyosin, a myofibrillar protein found only in invertebrates, has been widely studied as a vaccine candidate for both Schistosoma mansoni and Schistosoma japonicum. Recently, we demonstrated that Th2-biased immune responses to paramyosin are associated with resistance to reinfection with S. japonicum in humans; however, challenges in the pilot-scale production of schistosome paramyosin have hampered further studies of this promising vaccine candidate. Here we report a method for the pilot-scale expression and purification of recombinant S. japonicum paramyosin (rSj97). rSj97 was extracted from Escherichia coli inclusion bodies and purified with sequential anion-exchange, hydroxyapatite, and size exclusion chromatography. The purified rSj97 was >95% pure as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoretic analysis and was free of significant endotoxin contamination. We demonstrate that, like native paramyosin, rSj97 adopts an alpha-helical coiled-coil tertiary structure and binds immunoglobulin and collagen. Naïve mice infected with S. japonicum produce anti-rSj97 immunoglobulin G (IgG) antibodies as early as 4 weeks postinfection, while sera collected from S. japonicum-infected individuals contain anti-rSj97 IgE antibodies. Our method for pilot-scale production of recombinant full-length paramyosin will facilitate preclinical evaluation of paramyosin as a vaccine for schistosomiasis.

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Development of Inactivated FAKHRAVAC® Vaccine against SARS-CoV-2 Virus: Preclinical Study in Animal Models

Vaccines ◽

10.3390/vaccines9111271 ◽

2021 ◽

Vol 9 (11) ◽

pp. 1271

Author(s):

Soheil Ghasemi ◽

Kosar Naderi Saffar ◽

Firooz Ebrahimi ◽

Pezhman Khatami ◽

Arina Monazah ◽

...

Keyword(s):

Neutralizing Antibodies ◽

Vaccine Development ◽

Vaccine Candidate ◽

Rhesus Macaques ◽

Seroconversion Rate ◽

Pilot Scale ◽

Preclinical Study ◽

Scale Production ◽

Global Public Health ◽

Health Crisis

The recent viral infection disease pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has resulted in a global public health crisis. Iran, as one of the countries that reported over five million infected cases by September 2021, has been concerned with the urgent development of effective vaccines against SARS-CoV-2. In this paper, we report the results of a study on potency and safety of an inactivated SARS-CoV-2 vaccine candidate (FAKHRAVAC) in a preclinical study so as to confirm its potential for further clinical evaluation. Here, we developed a pilot-scale production of FAKHRAVAC, a purified inactivated SARS-CoV-2 virus vaccine candidate that induces neutralizing antibodies in Balb/c mice, guinea pigs, rabbits, and non-human primates (Rhesus macaques—RM). After obtaining ethical code of IR.IUMS.REC.1399.566, immunizations of animals were conducted by using either of three different vaccine dilutions; High (H): 10 μg/dose, Medium (M): 5 μg/dose, and Low (L): 1 μg/dose, respectively. In the process of screening for viral seeds, viral strains that resulted in the most severe clinical manifestation in patients have been isolated for vaccine development. The viral seed produced the optimal immunity against SARS-CoV-2 virus, which suggests a possible broader neutralizing ability against SARS-CoV-2 strains. The seroconversion rate at the H-, M-, and L-dose groups of all tested animals reached 100% by 28 days after immunization. These data support the eligibility of FAKHRAVAC vaccine candidate for further evaluation in a clinical trial.

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Development of pilot scale production process and characterization of a recombinant multiepitope malarial vaccine candidate FALVAC-1A expressed in Escherichia coli

Protein Expression and Purification ◽

10.1016/j.pep.2008.05.018 ◽

2008 ◽

Vol 61 (1) ◽

pp. 57-64 ◽

Cited By ~ 2

Author(s):

G. Ravi ◽

Krishna Ella ◽

M. Lakshmi Narasu

Keyword(s):

Escherichia Coli ◽

Production Process ◽

Vaccine Candidate ◽

Pilot Scale ◽

Scale Production ◽

Pilot Scale Production

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Pilot-Scale Production of Chito-Oligosaccharides Using an Innovative Recombinant Chitosanase Preparation Approach

Polymers ◽

10.3390/polym13020290 ◽

2021 ◽

Vol 13 (2) ◽

pp. 290

Author(s):

Chih-Yu Cheng ◽

Chia-Huang Tsai ◽

Pei-Jyun Liou ◽

Chi-Hang Wang

Keyword(s):

Cell Density ◽

Scale Up ◽

Cost Effective ◽

Pilot Scale ◽

Ionic Concentration ◽

Dihydrogen Phosphate ◽

Scale Production ◽

Sodium Dihydrogen Phosphate ◽

Selective Precipitation ◽

Pilot Scale Production

For pilot-scale production of chito-oligosaccharides, it must be cost-effective to prepare designable recombinant chitosanase. Herein, an efficient method for preparing recombinant Bacillus chitosanase from Escherichia coli by elimination of undesirable substances as a precipitate is proposed. After an optimized culture with IPTG (Isopropyl β-d-1-thiogalactopyranoside) induction, the harvested cells were resuspended, disrupted by sonication, divided by selective precipitation, and stored using the same solution conditions. Several factors involved in these procedures, including ion types, ionic concentration, pH, and bacterial cell density, were examined. The optimal conditions were inferred to be pH = 4.5, 300 mM sodium dihydrogen phosphate, and cell density below 1011 cells/mL. Finally, recombinant chitosanase was purified to >70% homogeneity with an activity recovery and enzyme yield of 90% and 106 mg/L, respectively. When 10 L of 5% chitosan was hydrolyzed with 2500 units of chitosanase at ambient temperature for 72 h, hydrolyzed products having molar masses of 833 ± 222 g/mol with multiple degrees of polymerization (chito-dimer to tetramer) were obtained. This work provided an economical and eco-friendly preparation of recombinant chitosanase to scale up the hydrolysis of chitosan towards tailored oligosaccharides in the near future.

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