Human papillomavirus (HPV) type 16 E7 protein bodies cause tumour regression in mice

Abstract Background Human papillomaviruses (HPV) are the causative agents of cervical cancer in women, which results in over 250 000 deaths per year. Presently there are two prophylactic vaccines on the market, protecting against the two most common high-risk HPV types 16 and 18. These vaccines remain very expensive and are not generally affordable in developing countries where they are needed most. Additionally, there remains a need to treat women that are already infected with HPV, and who have high-grade lesions or cervical cancer. Methods In this paper, we characterize the immunogenicity of a therapeutic vaccine that targets the E7 protein of the most prevalent high-risk HPV - type 16 – the gene which has previously been shown to be effective in DNA vaccine trials in mice. The synthetic shuffled HPV-16 E7 (16E7SH) has lost its transforming properties but retains all naturally-occurring CTL epitopes. This was genetically fused to Zera®, a self-assembly domain of the maize γ-zein able to induce the accumulation of recombinant proteins into protein bodies (PBs), within the endoplasmic reticulum in a number of expression systems. Results High-level expression of the HPV 16E7SH protein fused to Zera® in plants was achieved, and the protein bodies could be easily and cost-effectively purified. Immune responses comparable to the 16E7SH DNA vaccine were demonstrated in the murine model, with the protein vaccine successfully inducing a specific humoral as well as cell mediated immune response, and mediating tumour regression. Conclusions The fusion of 16E7SH to the Zera® peptide was found to enhance the immune responses, presumably by means of a more efficient antigen presentation via the protein bodies. Interestingly, simply mixing the free PBs and 16E7SH also enhanced immune responses, indicating an adjuvant activity for the Zera® PBs

Mutational analysis of the spike protein of SARS-COV-2 isolates revealed atomistic features responsible for higher binding and infectivity

Introduction: The perpetual appearance of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-COV-2), and its new variants devastated the public health and social fabric around the world. Understanding the genomic patterns and connecting them to phenotypic attributes is of great interest to devise a treatment strategy to control this pandemic.Materials and Methods: In this regard, computational methods to understand the evolution, dynamics and mutational spectrum of SARS-CoV-2 and its new variants are significantly important. Thus, herein, we used computational methods to screen the genomes of SARS-CoV-2 isolated from Pakistan and connect them to the phenotypic attributes of spike protein; we used stability-function correlation methods, protein-protein docking, and molecular dynamics simulation.Results: Using the Global initiative on sharing all influenza data (GISAID) a total of 21 unique mutations were identified, among which five were reported as stabilizing while 16 were destabilizing revealed through mCSM, DynaMut 2.0, and I-Mutant servers. Protein-protein docking with Angiotensin-converting enzyme 2 (ACE2) and monoclonal antibody (4A8) revealed that mutation G446V in the receptor-binding domain; R102S and G181V in the N-terminal domain (NTD) significantly affected the binding and thus increased the infectivity. The interaction pattern also revealed significant variations in the hydrogen bonding, salt bridges and non-bonded contact networks. The structural-dynamic features of these mutations revealed the global dynamic trend and the finding energy calculation further established that the G446V mutation increases the binding affinity towards ACE2 while R102S and G181V help in evading the host immune response. The other mutations reported supplement these processes indirectly. The binding free energy results revealed that wild type-RBD has a TBE of −60.55 kcal/mol while G446V-RBD reported a TBE of −73.49 kcal/mol. On the other hand, wild type-NTD reported −67.77 kcal/mol of TBE, R102S-NTD reported −51.25 kcal/mol of TBE while G181V-NTD reported a TBE of −63.68 kcal/mol.Conclusions: In conclusion, the current findings revealed basis for higher infectivity and immune evasion associated with the aforementioned mutations and structure-based drug discovery against such variants

Immunological and molecular epidemiological characteristics of acute and fulminant viral hepatitis A

<p>Abstract</p> <p>Background</p> <p>Hepatitis A virus is an infection of liver; it is hyperendemic in vast areas of the world including India. In most cases it causes an acute self limited illness but rarely fulminant. There is growing concern about change in pattern from asymptomatic childhood infection to an increased incidence of symptomatic disease in the adult population.</p> <p>Objective</p> <p>In-depth analysis of immunological, viral quantification and genotype of acute and fulminant hepatitis A virus.</p> <p>Methods</p> <p>Serum samples obtained from 1009 cases of suspected acute viral hepatitis was employed for different biochemical and serological examination. RNA was extracted from blood serum, reverse transcribed into cDNA and amplified using nested PCR for viral quantification, sequencing and genotyping. Immunological cell count from freshly collected whole blood was carried out by fluorescence activated cell sorter.</p> <p>Results</p> <p>Fulminant hepatitis A was mostly detected with other hepatic viruses. CD8⁺T cells count increases in fulminant hepatitis to a significantly high level (P = 0.005) compared to normal healthy control. The immunological helper/suppressor (CD4⁺/CD8⁺) ratio of fulminant hepatitis was significantly lower compared to acute cases. The serologically positive patients were confirmed by RT-PCR and total of 72 (69.2%) were quantified and sequenced. The average quantitative viral load of fulminant cases was significantly higher (<it>P </it>< 0.05). There was similar genotypic distribution in both acute and fulminant category, with predominance of genotype IIIA (70%) compared to IA (30%).</p> <p>Conclusions</p> <p>Immunological factors in combination with viral load defines the severity of the fulminant hepatitis A. Phylogenetic analysis of acute and fulminant hepatitis A confirmed genotypes IIIA as predominant against IA with no preference of disease severity.</p

Report on Influenza A and B Viruses: Their Coinfection in a Saudi Leukemia Patient

Purpose. Influenza A and B viruses are the leading cause of respiratory infections in children worldwide, particularly in developing countries. There is a lack of data on coinfection of influenza A and B viruses circulating in Saudi Arabia. In this study, we aimed to identify the circulation of influenza viruses that contribute to respiratory tract infections in Saudi children. Methods. We collected 80 nasopharyngeal aspirates (NPAs) from hospitalized children with acute respiratory illness (ARI) at Riyadh during the period extended from October 2010 till April 2011. Samples were tested for the common respiratory viruses including influenza viruses by RT-PCR. Results. Overall, 6 samples were found positive for influenza A and/or B viruses. Among these positive clinical samples, only one collected sample from a female one-year-old immunocompromised child with leukemia showed a coinfection with influenza A and B viruses. In present study coinfection was confirmed by inoculation of the clinical specimen in specific pathogenfree embryonating chicken eggs and identification of the virus isolates by hemagglutination and one-step RT-PCR. Conclusion. This study opens the scene for studying the role of influenza virus’s coinfection in disease severity and virus evolution. Further studies are required to better understand the clinical importance of viral coinfection

Differential expression of transforming growth factor-ßl and HBx enhances hepatitis B virus replication and augments host immune cytokines and chemokines

Background/Aims. This study investigated how HBV replication and host immune response are effected by reduced expression of TGF-ß1 and HBx.Material and methods. Short interfering RNA (siRNA) knockdown technology has been used to examine the role of TGF-ß1 in hepatitis B virus replication. The siTGF-ß1 has been transfected along with 1.3mer HBV x-null to investigate the knockdown effect of TGF-ß1 on HBV replication and host immune factors.Results. In this study, we found that diminished expression of TGF-ß1 and increased expression of HBx enhances HBV replication several folds. The differential expression of TGF-ß1 and HBx also stimulated transcriptional viral replicative intermediate (pgRNA) and secretion of core and ‘e’ antigen at translational level. Consequently, several cytokines such as IL–2, IL–8 and chemokine monocyte-chemoattractant protein (MCP–1) were increased significantly in response to stimulation of HBV replication. In contrast, TNF-α and RANTES mRNA expression increased insignificantly in response to enhanced HBV replication.Conclusions. We concluded that reduced expression of TGF-ß1 together with HBx expression stimulate HBV replication and immune response, although the underlying mechanism of stimulation most likely differs

Design of a highly effective therapeutic HPV16 E6/E7-specific DNA vaccine: optimization by different ways of sequence rearrangements (shuffling).

Persistent infection with the high-risk Human Papillomavirus type 16 (HPV 16) is the causative event for the development of cervical cancer and other malignant tumors of the anogenital tract and of the head and neck. Despite many attempts to develop therapeutic vaccines no candidate has entered late clinical trials. An interesting approach is a DNA based vaccine encompassing the nucleotide sequence of the E6 and E7 viral oncoproteins. Because both proteins are consistently expressed in HPV infected cells they represent excellent targets for immune therapy. Here we report the development of 8 DNA vaccine candidates consisting of differently rearranged HPV-16 E6 and E7 sequences within one molecule providing all naturally occurring epitopes but supposedly lacking transforming activity. The HPV sequences were fused to the J-domain and the SV40 enhancer in order to increase immune responses. We demonstrate that one out of the 8 vaccine candidates induces very strong cellular E6- and E7- specific cellular immune responses in mice and, as shown in regression experiments, efficiently controls growth of HPV 16 positive syngeneic tumors. This data demonstrates the potential of this vaccine candidate to control persistent HPV 16 infection that may lead to malignant disease. It also suggests that different sequence rearrangements influence the immunogenecity by an as yet unknown mechanism

Comparison of Low-Versus High-Dose Steroids in the Clinical Outcome of Hospitalized COVID-19 Patients

(1) Objectives: Patients with COVID-19 infection have been given various formulations and dosages of steroids over the last year and a half. This study aims to compare the effects of different formulations and doses of steroids on the 30 day in-hospital clinical outcome of patients with severe COVID-19 infection. (2) Material and Methods: An analysis of a retrospective cohort was carried out on patients with severe COVID-19 infection in a high-dependency unit (HDU) between February and July 2021. In total, 557 patients were included in this study. Patients who did not receive steroids (124) were excluded. Patients were divided into three groups based on dosages of steroids (Dexamethasone = 6 mg/day, Dexamethasone &gt; 6 mg/day, and Methylprednisolone = 500 mg/day), given for 10 days. First, clinical outcome was evaluated on the 10th day of steroid administration in relation to mode of oxygen delivery. Then, Kaplan&ndash;Meier analysis was employed to determine 30 day in-hospital survival in relation to the use of steroid. (3) Results: Three groups were statistically equal according to biochemical characteristics. After 10 days of Methylprednisolone = 500 mg/day vs. Dexamethasone = 6 mg/day, 10.9% vs. 6.2% of patients required invasive ventilation (p = 0.01). The 30 day in-hospital mortality was lowest, 3%, in individuals receiving Dexamethasone = 6 mg/day, compared to 3.9% in individuals receiving Dexamethasone &gt; 6 mg/day and 9.9% in individuals receiving Methylprednisolone = 500 mg/day, respectively. The median elapsed time was longer than 28 days between admission and outcome for Dexamethasone = 6 mg/day, compared to 18 days for Dexamethasone &gt; 6 mg/day and 17 days for Methylprednisolone = 500 mg/day (p = &lt; 0.0001). Dexamethasone = 6 mg/day was found to be a positive predictor of clinical outcome in COVID-19 patients on regression analysis. (4) Conclusions: Low-dose Dexamethasone (6 mg/day) is more effective than high-dose Dexamethasone and Methylprednisolone in improving the survival outcome of severe COVID-19 cases

The role of TLR7 agonists in modulating COVID-19 severity in subjects with loss-of-function TLR7 variants

Abstract We investigate the mechanism associated with the severity of COVID-19 in men with TLR7 mutation. Men with loss-of-function (LOF) mutations in TLR7 had severe COVID-19. LOF mutations in TLR7 increased the risk of critical COVID by 16.00-fold (95% confidence interval 2.40–106.73). The deleterious mutations affect the binding of SARS-CoV2 RNA (− 328.66 ± 26.03 vs. − 354.08 ± 27.70, p = 0.03) and MYD88 (β: 40.279, p = 0.003) to TLR7 resulting in the disruption of TLR7-MyD88-TIRAP complex. In certain hypofunctional variants and all neutral/benign variants, there is no disruption of TLR7-MyD88-TIRAP complex and four TLR7 agonists showed binding affinity comparable to that of wild protein. N-acetylcysteine (NAC) also showed a higher binding affinity for the LOF variants (p = 0.03). To conclude, TLR7 LOF mutations increase the risk of critical COVID-19 due to loss of viral RNA sensing ability and disrupted MyD88 signaling. Majority of hypofunctional and neutral variants of TLR7 are capable of carrying MyD88 signaling by binding to different TLR7 agonists and NAC