ABSTRACT
Background and Aim: The COVID-19 disease is an emerging infectious disease that appeared in December 2019 in Wuhan, China. An uncontrolled systemic inflammatory response is one of the primary mechanisms causing death in this disease. In this study, the expression levels of some inflammatory cytokines, vitamin D, and some hematological and biochemical parameters were compared in patients with severe COVID-19 and mild types. Materials and Methods: In this cross-sectional study, 60 blood samples were taken from 30 severe coronavirus patients and 30 mild coronavirus patients. The expression levels of cytokines such as IL (interleukin)-6, interferon (IFN)-α, IL-12, transforming growth factor (TGF) β, IL-8 and tumor necrosis factor (TNF)-α were evaluated using Real-time PCR. A T-test was used for Statistical Analysis. Results: IL-6, IFN-α, IL-12, TGF-β, IL-8, and TNF-α cytokines in the peripheral blood of severe patients, were positive in 28/30 (93.33%), 27/30 (90%), 24/30 (80%), 25/30 (83.33%), 26/30 (86.66%), and 27/30 (90%) respectively. The positive rate of these cytokines in the mild patients were 20/30 (66.67%), 21/30 (70%), 18/30 (60%), 17/30 (56.67%), 19/30 (63.33%), 18/30 (60%), respectively. There was a statistically significant difference between these two groups in terms of cytokines biomarkers. A significant difference was found between both groups in terms of the serum level of lactate dehydrogenase (LDH), the mean number of lymphocytes and neutrophils as well as the mean percentage of neutrophils/ lymphocytes ratio (NLR). Conclusion: The expression of cytokine genes and their release into the peripheral blood was increased in both severe and mild patients with COVID-19. However, they were more intense in patients with severe symptoms than those with mild symptoms and can cause inflammatory and even destructive reactions. Vitamin D deficiency plays no role in causing severe COVID-19 in patients without risk factors. Severe COVID-19 is characterized by elevated serum levels of LDH and NLR≥3.45. © 2022. This is an original open-access article distributed under the terms of the Creative Commons Attribution-noncommercial 4.0 International License which permits copy and redistribution of the material just in noncommercial usages with proper citation.
ABSTRACT
Avian infectious bronchitis (IB) is an acute, highly infectious and contagious viral disease of chickens caused by avian infectious bronchitis virus (IBV) belonging to the genus Coronavirus and family Coronaviridae. It can affect all age groups of birds. The toll-like receptors (TLRs) are a major class of innate immune pattern recognition receptors that have a key role in immune response and defense against various infections.The TLRs are essential for initiation of innate immune responses and in the development of adaptive immune responses. An in ovo model was employed to study the antiviral activity of TLR ligands (Pam3CSK4, LPS and CpG ODN) on replication of IBV. It was hypothesized that optimum dose and specific timing of TLR ligands may reduce viral load of IBV in specific pathogen free (SPF) embryonated chicken eggs (ECEs). Further, the mechanism involved in the TLR-mediated antiviral response in chorioallantoic membrane (CAM) of ECEs was investigated. The ECEs of 9-11 days old were treated with different doses (high, intermediate and low) of TLR-2 (Pam3CSK4), TLR-4 (LPS) and TLR-21 (CpG ODN) ligands. In addition, to know the timing of TLR ligand treatment, six time intervals were analyzed viz. 36, 24 and 12 h prior to infection, time of infection (co-administration of TLR ligands and avian IBV) and 12 and 24 h post-IBV infection. For studying the relative expression of immuno-stimulatory genes (IFN-α, IFN-ß, IFN-γ, IL-1ß, iNOS and OAS) in CAM, TLR ligands were administered through intra-allantoicroute and CAM were collected at 4, 8 and 16 h post treatment. The results demonstrated that intermediate dose of all the three TLR ligands significantly reduced virus titers and used in the present study. However, the LPS reduced virus titer pre- and post-IBV infection but Pam3CSK4 and CpG ODN reduced only pre-IBV infection. Further analysis showed that TLR ligands induced IFN-γ, IL-1ß and IFN stimulated genes viz. iNOS and OAS genes in CAM. The present study pointed towards the novel opportunities for rational design of LPS as immuno-stimulatory agent in chickens with reference to IBV. It may be speculated that in ovo administration of these TLR ligands may enhance resistance against viral infection in neonatal chicken and may contribute towards the development of more effective and safer vaccines including in ovo vaccines.