Expression of the Mouse HSP27 Chaperone in CHO-K1 Cells for the Enhancement of Viable Cell Density in Batch Culture

Mohammad Reza Amini, Azam Rahimpour, Reyhaneh Hoseinpoor, Masoumeh Rajabibazl

Trends in Peptide and Protein Sciences, Vol. 7 (2022), , Page 1-5 (e2)
https://doi.org/10.22037/tpps.v7i.37418

Chinese hamster ovary (CHO) cells are extremely vulnerable to cell viability loss in culture despite the availability of different nutrients supplementation strategies. As a result, extending the culture lifetime can profoundly increase recombinant protein expression. Overexpression of HSP27 and its anti-apoptotic effects have been shown in human cell lines in previous studies. In the current study, mouse HSP27 (mHSP27) was cloned in pcDNA 3.1 hygro expression vector and was expressed in CHO-K1 cells to assess its impacts on cell viability and growth. Expression of mHSP27 in CHO-K1 cells was confirmed using RT-PCR. A 3-fold enhancement in peak viable cell density of mHSP27 transfected clones was observed, and culture viability loss was delayed by 2 days compared to un-transfected cells. In future studies, the resulting mHSP27 CHO-K1 cells could be employed as a novel host system for the transient and stable expression of therapeutic recombinant proteins.


HIGHLIGHTS


  • Cell engineering is an effective strategy to cope with apoptosis in CHO cells.

  • HSP27 is involved in mammalian cell apoptosis.

  • Expression of the mouse HSP27 increased the viability and cell density of CHO-K1 cells.

Preparation and In Vitro Characterization of Crocin-loaded Casein Hydrogels

Fatemeh Mehryab, Fatemeh Taghizadeh, Azadeh Haeri

Trends in Peptide and Protein Sciences, Vol. 7 (2022), , Page 1-9 (e3)
https://doi.org/10.22037/tpps.v7i.37420

Crocin, the main active constituent of saffron, has many important biological activities. Due to its anti-inflammatory properties, crocin can be potentially effective in different pathological conditions including oral ulcers. Novel drug delivery systems such as hydrogels have been used to increase the stability of crocin and provide a controlled release of this compound. Casein is the main protein of milk that possesses suitable properties for the fabrication of hydrogels. In this paper, casein-based hydrogels with different casein to crocin weight ratios were synthesized using the acid-gelation method. The prepared crocin-loaded hydrogels were characterized regarding their rheological behavior, drug content, swelling ratio, surface morphology, thermal stability, and in vitro release profile. The structure of casein hydrogels was characterized using Fourier transform infrared and X-ray diffraction. All formulations exhibited a pseudoplastic rheological behavior and there was no statistically significant difference in viscosity among them. Hydrogel with casein to crocin weight ratio of 10:1 had larger pores and demonstrated a higher swelling percentage and suitable thermal stability. All casein-based hydrogels demonstrated a slow release of crocin over 24 hours and the hydrogel with lower casein to crocin weight ratio had an increased release rate. Taken together, casein-based hydrogels were found to be effective carriers to provide a controlled release system for crocin delivery.


HIGHLIGHTS


  • Casein-based hydrogels were developed for delivery of crocin.

  • Casein-based hydrogels provided a controlled in vitro release profile for crocin.

  • Hydrogel with a lower casein ratio exhibited a higher release rate of crocin.

Controversy Between In Vitro Biological Activities of a Novel Designed Antimicrobial Peptide and Its In Silico Predicted Activities

Fariba Fathi , Maryam Ghobeh , Arash Mahboubi, Maryam Tabarzad

Trends in Peptide and Protein Sciences, Vol. 7 (2022), , Page 1-12 (e4)
https://doi.org/10.22037/tpps.v7i.38346

Due to their unique mechanisms of action, antimicrobial peptides (AMPs) are promising candidates to combat different infectious diseases. They usually non-specifically interact with the bacterial cell membrane, create pores in their membrane and increase its permeability which causes the death of pathogens. In the design and development of AMPs, in silico strategies have been developed to enhance the function and activity of natural peptides. In this study, in silico approaches were used to develop a novel AMP with several extra bioactivities. Then, the designed AMP were analyzed through computational methods by in vitro experiments. Bioinformatics research revealed a 10-amino-acid peptide (LVSARIRCPK) having antibacterial, anti-biofilm, antiviral, antifungal, and anti-inflammatory effects. However, only the antiviral capabilities of the peptide were validated in the experimental analysis of antibacterial, antifungal, and antiviral activities. This data suggests that; while bioinformatics approaches have greatly advanced in recent years, more optimization work has to be done in order to attain high accuracy and minimize mistakes.


HIGHLIGHTS


  • A novel 10 residues anti-microbial peptide was designed using bioinformatics tools.

  • In vitro analysis showed that this novel AMP did not have efficient antimicrobial activities.

  • Stringencies of bioinformatics criteria thresholds setting may result in better design.

Since the appearance of acquired immunodeficiency syndrome (AIDS) disease, millions of people got infected, thousands are died and many suffered from its complications. One of the chronic and late symptoms of AIDS is lipodystrophy that leads to losing of fat in some parts of the body while gaining it at other organs and sites. One of the main targets in drug development for management of lipodystrophy is growth hormone-releasing hormone (GHRH) receptor. As a secondary metabolite from plants, leginsulin is a peptide with 37 amino acids and considered as hormone-like peptide. In this study, through in silico approaches, binding of leginsulin and GHRH receptor was studied. The results showed strong binding of the two molecules with docking score of -324.16 and ligand RMSD of 47.26. The molecular dynamic investigation also revealed these two proteins remained bound for almost 104 ns. Evaluation of the peptide toxicity in the body had shown that it is not toxic to the human organs and also, it doesn’t pass through the blood brain barrier. The results support the use of legumes as a source of leginsulin for potential management of lipodystrophy in the patients with AIDS.


HIGHLIGHTS


  • Leginsulin is a plant secondary metabolite with 37 amino acids peptide structure.

  • Binding of leginsulin and GHRH receptor was studied through in silico approaches.

  • Results support the leginsulin as a potential management of lipodystrophy in AIDS patients.