Viral glycoproteins: biological role and application in diagnosis

Oxidative damage markers and inflammatory cytokines are altered in patients suffering with post-chikungunya persisting polyarthralgia

Redox homoeostasis is necessary for the maintenance of living systems. Chikungunya viral infection manifests into joint inflammation and debilitating polyarthralgia affecting the life style of the patient badly. The disease pathophysiology is poorly understood and there is a lack of targeted therapeutics. The pathogenic role of free radicals in arthritis is well established. This study aims for the first time to evaluate the status of several standard oxidative stress markers and their correlation in chikungunya patients suffering with polyarthralgia. Expression of Siglec-9 on monocytes; which can modulate oxidative stress is studied along with intracellular reactive oxygen species (ROS), cellular lipid and protein damage markers in chikungunya patients with/without persisting polyarthralgia along with healthy controls. Furthermore, plasma NO level, antioxidant status was investigated along with some inflammatory cytokines namely IL-6, IFN-γ, CXCL-9, IL-10 and TGFβ1. Interestingly, all oxidative damage markers are altered significantly in groups but their alteration levels vary in patients with/without persisting polyarthralgia. Siglec-9 expression level is increased in patients revealing cellular response to manage oxidative stress with respect to controls. Correlation studies reveal that intracellular ROS correlates well with most of the studied parameters but the correlation coefficient (Pearson r) differs with disease manifestation demonstrating strong role of these factors in a pro-oxidant milieu. The presence of free radicals increases the availability of neoantigens continuously, which possibly further cascades oxidative damage and development of persisting polyarthralgia.

Intracellular ROS generated in chikungunya patients with persisting polyarthralgia can be reduced by Tinospora cordifolia leaf extract

Chikungunya (CHIK) is an arboviral infection having huge global burden affecting the life style of the patient badly due to debilitating polyarthralgia. This study aims to evaluate intracellular reactive oxygen species (ROS) in peripheral blood of patients suffering with persisting polyarthralgia post CHIK infection and the potential of Tinospora cordifolia leaf extract in scavenging those free radicals in peripheral blood mononuclear cells (PBMC) of the patient. Peripheral blood was collected from written informed consented patients and intracellular ROS was measured in PBMC of patients suffering with persisting polyarthralgia 3 months post CHIK infection followed by the study of free radical scavenging by T. cordifolia leaf extract in those cells through flow cytometry. Control population comprising healthy donors were also included in the study. As compared to healthy subjects, twofold higher Intracellular ROS (17.89 ± 1.007 vs. 37.96 ± 1.510, P < 0.0001) was found in patient PBMC. Ex-vivo treatment of those PBMC with ethanolic extract of T. cordifolia leaf (1 μg/mL) decreased intracellular ROS significantly by twofold (P < 0.0001). This study reports that CHIK infection produces high level of intracellular ROS in the patients suffering with persisting polyarthralgia, which was significantly scavenged by ex vivo treatment with T. cordifolia leaf extract.

Computer aided epitope design as a peptide vaccine component against Lassa virus

Lassa virus (LASV) is an arena virus causing hemorrhagic fever and it is endemic in several regions of West Africa. The disease-causing virus records high mortality rate in endemic regions due to lack of appropriate treatment and prevention strategies. Therefore, it is of interest to design and develop viable vaccine components against the virus. We used the Lassa virus envelope glyco-proteins as a vaccine target to identify linear peptides as potential epitopes with immunogenic properties by computer aided epitope prediction tools. We report a T-cell epitope 'LLGTFTWTL' and a B-cell epitope 'AELKCFGNTAVAKCNE' with predicted potential immunogenicity for further in vivo and in vitro consideration.