A Novel Cell-based In vitro Assay for Antiviral Activity of Interferons α, β, and γ by qPCR of MxA Gene Expression

Interdisciplinary gene manipulation, molecular cloning, and recombinant expression of modified human growth hormone isoform-1 in E. coli system

BACKGROUND

Growth hormone (GH) is a hormone that promotes growth, cell reproduction, and cell restoration in humans and animals.

OBJECTIVES

Production of recombinant human growth hormone (rhGH) in Escherichia coli (E. coli) and assessment of its characteristics and proliferation stimulatory activity.

METHODS

The hGH gene was cloned into a pET 3a expression vector and transformed into a competent E. coli cell. The refolded hGH was purified, Western blot and batch fermentation were performed. Cell cytotoxicity was tested on Vero cells, and MALDI-TOF and Nano-LC-ESI MS/MS were used for protein and target peptide analysis.

RESULTS

Induced rhGH was purified with a concentration of 511.9 mg/ml. Western blot confirmed the molecular identity of rhGH, showing a single 22 kDa band. The bacterial growth at OD600 after 24 h in batch fermentation was 9.78 ± 0.26, and wet cell weight (WCWg/L) was 15.2 ± 0.32. Purified rhGH activity on Vero cells was 0.535 IU/mg. LC-MS/MS analysis revealed a score of 70.51 % and coverage of 60.37 %.

CONCLUSION

Biologically active native rhGH protein was successfully expressed in the Prokaryotic system. Our goal is to increase its production on a pilot level in the native form at a high activity effect identical to isoform 1.

Phages for treatment of Staphylococcus aureus infection

Combating multi-drug resistant bacterial infections should be a universal urgency. The gram- positive Staphylococcus aureus (S. aureus) bacteria are generally harmless; healthy people frequently have them on their skin and nose. These bacteria, for the most part, produce no difficulties or only minor skin diseases. Antibiotics and cleansing of the affected region are usually the treatments of choice. S. aureus can become virulent causing serious infections that may lead to pustules to sepsis or death. Normally, it is thought that antibiotics may solve problems concerning bacterial infection; but unfortunately, Staphylococci have evolved mechanisms to resist drugs. Methicillin-Resistant Staphylococcus aureus (MRSA); both in hospitals and in the community, infections are evolving into dangerous pathogens. Health care practitioners may need to use antibiotics with more adverse effects to treat antibiotic-resistant S. aureus infections. Amid existing efforts to resolve this problem, phage therapy proposes a hopeful alternate to face Staphylococcal infections. When the majority of antibiotics have failed to treat infections caused by multidrug-resistant bacteria, such as methicillin- and vancomycin-resistant S. aureus, phage therapy may be an option. Here, we appraise the potential efficacy, current knowledge on bacteriophages for S. aureus, experimental research and information on their clinical application, and limitations of phage therapy for S. aureus infections.

Emerging concepts of type I interferons in SLE pathogenesis and therapy

Type I interferons have been suspected for decades to have a crucial role in the pathogenesis of systemic lupus erythematosus (SLE). Evidence has now overturned several long-held assumptions about how type I interferons are regulated and cause pathological conditions, providing a new view of SLE pathogenesis that resolves longstanding clinical dilemmas. This evidence includes data on interferons in relation to genetic predisposition and epigenetic regulation. Importantly, data are now available on the role of interferons in the early phases of the disease and the importance of non-haematopoietic cellular sources of type I interferons, such as keratinocytes, renal tubular cells, glial cells and synovial stromal cells, as well as local responses to type I interferons within these tissues. These local effects are found not only in inflamed target organs in established SLE, but also in histologically normal skin during asymptomatic preclinical phases, suggesting a role in disease initiation. In terms of clinical application, evidence relating to biomarkers to characterize the type I interferon system is complex, and, notably, interferon-blocking therapies are now licensed for the treatment of SLE. Collectively, the available data enable us to propose a model of disease pathogenesis that invokes the unique value of interferon-targeted therapies. Accordingly, future approaches in SLE involving disease reclassification and preventative strategies in preclinical phases should be investigated.

Possible internal viral shedding and interferon production after clinical recovery from COVID-19: Case report

A 70-year-old man underwent off-pump coronary artery bypass grafting 28 days after his recovery from coronavirus disease 2019 (COVID-19), which was confirmed by a negative polymerase chain reaction (PCR) test result for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from a nasopharyngeal swab. The PCR test result was also negative for nasopharyngeal sampling 5 days prior to the surgery. However, his redundant saphenous vein and sputum through the endotracheal tube that was taken on the operative day showed the presence of SARS-CoV-2 by PCR. Immunohistochemical analysis of Spike and Nucleoprotein of the saphenous vein showed small clusters of each antigen-positive speckle. Ultrastructural imaging of the saphenous vein showed virus-like particles. The cell-based assay suggested that the patient’s serum contained a higher concentration of type-I interferons than that of healthy control sera. These observations suggest that internal viral shedding and, to some extent, innate immune responses continue after COVID-19 recovery.

Soluble Receptor Isoform of IFN-Beta (sIFNAR2) in Multiple Sclerosis Patients and Their Association With the Clinical Response to IFN-Beta Treatment

Purpose

Interferon beta receptor 2 subunit (IFNAR2) can be produced as a transmembrane protein, but also as a soluble form (sIFNAR2) generated by alternative splicing or proteolytic cleavage, which has both agonist and antagonist activities for IFN-β. However, its role regarding the clinical response to IFN-β for relapsing-remitting multiple sclerosis (RRMS) is unknown. We aim to evaluate the in vitro short-term effects and after 6 and 12 months of IFN-β therapy on sIFNAR2 production and their association with the clinical response in MS patients.

Methods

Ninety-four RRMS patients were included and evaluated at baseline, 6 and 12 months from treatment onset. A subset of 41 patients were classified as responders and non-responders to IFN-β therapy. sIFNAR2 serum levels were measured by ELISA. mRNA expression for IFNAR1, IFNAR2 splice variants, MxA and proteases were assessed by RT-PCR. The short-term effect was evaluated in PBMC from RRMS patients after IFN-β stimulation in vitro.

Results

Protein and mRNA levels of sIFNAR2 increased after IFN-β treatment. According to the clinical response, only non-responders increased sIFNAR2 significantly at both protein and mRNA levels. sIFNAR2 gene expression correlated with the transmembrane isoform expression and was 2.3-fold higher. While MxA gene expression increased significantly after treatment, IFNAR1 and IFNAR2 only slightly increased. After short-term IFN-β in vitro induction of PBMC, 6/7 patients increased the sIFNAR2 expression.

Conclusions

IFN-β administration induces the production of sIFNAR2 in RRMS and higher levels might be associated to the reduction of therapeutic response. Thus, levels of sIFNAR2 could be monitored to optimize an effective response to IFN-β therapy.

Purified recombinant human Chromogranin A N46 peptide with remarkable anticancer effect on human colon cancer cells

Human Chromogranin A N46 (CGA-N46) is a weak cationic α-helical peptide with wide-spectrum antibacterial, fungal, and anticancer activities. In this study, the recombinant human CGA-N46 peptide was expressed successfully in Escherichia coli. The gene of CGA-N46 was cloned into the expression vector pET-15b without a fusion tag at the N terminus and the peptide was expressed using Isopropyl-β-d-thiogalactoside (IPTG) as an inducer. Using 8 M guanidinium HCl, inclusion bodies containing the peptide were purified and solubilized. The rhCGA-N46 peptide was purified using Q-FF anion exchange column. The cytotoxicity of the purified rhCGA-N46 peptide was investigated on WI-38 human lung normal cell line. The anticancer activity was studied on human colon cancer cell line; HCT-116 cell line. Besides, the possible involvement of rhCGA-N46 peptide in regulating apoptotic signal pathways was analyzed by detecting the expression levels of BCL2, BID, and CAS-8 in the treated cells. The results concluded that the active peptide recovery was up to 41.98%. The purified rhCGA-N46 was safe on normal cells with IC₅₀ = 227.74 µg/ml (40.67 µM) and had an obvious anticancer effect on colon cancer cells with IC₅₀ = 1.997 µg/ml (356.6 nM). The expression level of BCL2 was down-regulated and BID and CAS-8 were up-regulated significantly in treated HCT-116 cells compared to untreated. In conclusion, the rhCGA-N46 peptide was produced successfully in the native form with promising anti-colon cancer activity.