The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is an emergent infectious pathogen causing an acute respiratory disease called corona virus disease 2019 (COVID-19). Virus transmission may occur by contact, droplet, airborne or via contaminated surfaces. In efforts to effectively control the COVID-19 outbreak, the world health organization (WHO) and the Saudi Ministry of Health (MOH) have advised the public to practice protective measures to reduce transmission of the virus and reduce incidence of infection. These measures include hand washing, wearing masks and gloves and avoidance of touching the face with unwashed hands. The current study aimed to investigate knowledge and adherence of the Saudi population to these protective actions during the pandemic. After determining the required sample size using power analysis, a cross-sectional online self-reported survey of 5105 Saudi residents was conducted between 25th March to 17th April 2020 to evaluate public knowledge of COVID-19. Participants were all aged 18 years or above, Arabic speakers and residents of Saudi Arabia. Scores were calculated based on knowledge and adherence of the individuals to protective measures. About 90% of participants exhibited a high level of knowledge (scored 2/2) and practice (scored > 3/6) in relation to hand hygiene and wearing gloves and masks. Practice scores were positively associated with females and individuals with high income. Lower practice scores were linked to youth and residents of the northern and western regions of the Kingdom. Over two thirds of participants preferred hand washing to alcohol disinfection, and the frequency and performance of hand washing improved during the pandemic for more than half of respondents. Overall, the findings reflected high public knowledge of SARS-CoV2 transmission routes and adherence to personal protective measures. However, public awareness campaigns with an emphasis on the youth and individuals with low education and income are required to improve overall practice.

The last few months of 2019 witnessed the emergence, rise and rapid spread of a novel coronavirus known as severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), causing an acute respiratory disease called coronavirus disease 2019 or Covid-19. Severe pathological manifestations of the disease in the infected population with comorbidities are linked to acute respiratory distress syndrome (ARDS), associated with an exaggerated synthesis and expression of cytokines, leading to a systemic inflammatory response also known as a cytokine storm (CS). Elderly patients (>60 years of age) showed more deaths in Covid-19 infection. Age-related immune imbalance increases patient susceptibility to CS. In acute Covid-19 infection, it is difficult to minimize or control the overproduction of cytokines; hence, limited medical treatments are effective. This review aims to provide an overview of the current knowledge of involvement of cytokines in SARS-CoV-2 infection, susceptibility factors for the accompanying cytokine storm in severe Covid-19 cases and possible treatment strategies.

Glutamic acid decarboxylase-65 (GAD(65)) is an immunological marker of type 1 autoimmune diabetes. High titre of autoantibodies against GAD(65) (GAD(65)Abs) have also been detected in some other autoimmune diseases. In search of a potential immunological marker of type 1 diabetes, in vitro GAD(65) was modified by hydroxyl radical followed by the study of structural and conformational perturbed protein by different spectroscopic techniques (UV, fluorescence and CD) and thermal denaturation profile. Binding studies of circulating autoantibodies from diabetic groups (type 1 and type 2) with native and reactive oxygen species (ROS) modified GAD(65), exhibited high recognition of type 1 diabetic serum autoantibodies with modified antigen (p < 0.001) over unmodified GAD(65). Binding specificity of isolated IgG of patients (n = 17) from each diabetic group and control group (n = 10) was checked by inhibition enzyme linked immunosorbent assay (ELISA) and quantitative precipitin titration assay. Relative affinity of ROS-GAD(65)Abs for modified and native GAD(65) was in the order of 1.56 x 10(- 6) and 2.72 x 10(- 7) M, as calculated by Langmuir plot. In coherence, ROS oxidation of GAD(65) causes conformational perturbation, generating highly immunogenic unique neoepitopes that may be one of the factors in antigen-driven induction of type 1 diabetes autoantibodies that can serve as a potential marker in early diagnosis/prognosis of the disease.

Aging causes gradual changes in free radicals, antioxidants, and immune-imbalance in the elderly. This study aims to understand links among aging, gluco-oxidative stress, and autoantibodies in asymptomatic individuals. In vitro glycation of human serum albumin (Gly-HSA) induces appreciable biochemical changes. Significant inhibition of advanced glycation end products (AGEs) formation was achieved using garlic extract (53.75%) and epigallocatechin-3-gallate from green tea (72.5%). Increased amounts of serum carbonyl content (2.42 ± 0.5) and pentosidine (0.0321 ± 0.0029) were detected in IV-S (S represent smokers) vs. IV group individuals. Direct binding ELISA results exhibited significantly high autoantibodies against Gly-HSA in group IV-S (0.55 ± 0.054; p < 0.001) and III-S (0.40 ± 0.044; p < 0.01) individuals as compared to the age matched subjects who were non-smokers (group IV and III). Moreover, high average percent inhibition (51.3 ± 4.1%) was obtained against Gly-HSA in IV-S group individuals. Apparent association constant was found to be high for serum immunoglobulin-G (IgG) from group IV-S (1.18 × 10−6 M) vs. serum IgG from IV group (3.32 × 10−7 M). Aging induced gluco-oxidative stress and AGEs formation may generate neo-epitopes on blood-proteins, contributing to production of autoantibodies in the elderly, especially smokers. Use of anti-glycation natural products may reduce age-related pathophysiological changes.

Background: Depression and smoking contribute to the prognosis of autoimmune rheumatoid arthritis (RA). Advanced glycation end products (AGEs) are also detected in RA patients. This study correlates RA in patients with various levels of depression and a history of smoking through the detection of antibodies against AGEs of proteins. Methods: Sixty RA subjects were selected and divided into 4 groups based on their levels of depression and smoking habits. The division was as follows: group I consisted of RA patients classified as depressed (RA-D); group II consisted of RA patients with a history of smoking (RA-S); group III consisted of RA patients suffering from depression who were also smokers (RA-DS); and group IV consisted of patients with RA alone (RA-A), i.e., not depressed and non-smokers. In vitro human serum albumin (HSA) was modified by glucose, and the modifications were studied by biochemical and biophysical techniques. Glycated (G)-HSA was used as an antigen, and autoantibodies against G-HSA (G-HSA-Abs) were screened in serum samples of different groups of RA subjects. Oxidative stress levels in all patients and healthy individuals were analyzed by protein-bound carbonyl content estimations. Results: Significant biochemical and biophysical changes were detected in G-HSA when compared to native (N)-HSA. All patients and control subjects were screened for circulating G-HSA-Abs and N-HSA-Abs. From the cohort of different samples, serum autoantibodies from RA-DS showed a high recognition of G-HSA-Abs titres compared to RA-D or RA-S. RA-A exhibited the least binding of circulating G-HSA-Abs of all the groups. The oxidative stress marker, the carbonyl content also exhibited highest levels in RA-DS, followed by RA-D and RA-S. Band shift assay showed the highest titres of immunoglobulin G in the serum samples of RA-DS. Conclusions: Smoking and concomitant depression in RA subjects may lead to enhanced oxidative stress levels responsible for the gradual formation and/or exposing of cryptic epitopes on HSA that induce the production of G-HSA-Abs. Hence, we postulate that by reducing depression and corresponding oxidative stress, it may be possible to control or limit the severity of the precipitation of RA disease activity and improve prognosis.