Human Adenoviruses Role in Ophthalmic

Abstract

Background:Ophthalmic pterygium is a common benign lesion of unknown origin and the pathogenesis might be vision-threatening. This problem is often associated with exposure to solar light. Recent evidence suggests that potentially oncogenic viruses such as human papillomavirus and Epstein-Barr virus may be involved in the pathogenesis of pterygia. Expression of specific adenovirus genes such as E1A and E1B, which potentially have many functions, may contribute to their oncogenic activity as well as relevance to cellular immortalization.Objectives:For the first time, we aimed to investigate involvement of adenoviruses in pterygium formation.Patients and Methods:Fifty tissue specimens of pterygium from patients undergoing pterygium surgery (as cases), 50 conjunctival swab samples from the same patients and 10 conjunctival biopsy specimens from individuals without pterygium such as patients undergoing cataract surgery (as controls) were analyzed for evidence of adenovirus infection with polymerase chain reaction using specific primers chosen from the moderately conserved region of the hexon gene. Furthermore, β-globin primers were used to access the quality of extracted DNA. Data was analyzed using SPSS (version 16) software.Results:Of 50 patients, 20 were men and 30 women with mean age of 61.1 ± 16.9 years ranged between 22 and 85 years. All samples of pterygia had positive results for adenoviruses DNA with polymerase chain reaction, but none of the negative control groups displayed adenoviruses. The pterygium group and the control groups were β-globin positive. Direct sequencing of PCR products confirmed Adenovirus infection.Conclusions:Adenoviruses might act as a possible cause of pterygium formation and other factors could play a synergistic role in the development. However, further larger studies are required to confirm this hypothesis.

Human papilloma virus presence and its physical status in primary pterygium

“…On the other hand, pterygium is considered a neoplastic disorder, showing morphological features such as an uncontrolled cellular proliferation process and alterations in suppressor tumor genes as p53 and p27. It has been shown a relation between UV radiation and oncogenic viruses such as probable mutagenic factors for the p53 gene that lead to abnormal expression in the limbal basal stem of all pterygia and limbal tumors [ 44 ].…”

“…It has been described that UV is one of the most important agents in generate reactive oxygen species (ROS), and this could affect the expression or generating mutation of p53, and this is one of the hypotheses about pterygium development [ 44 ]. As we mentioned above, HPV-E6 is also associated with the degradation/inactivation of p53 (Chakia et al, 2019).…”

Overexpression of CFH gene in pterygiumv patients

“…Some of these effects, as well as other forms of stress, may activate the complement system [24] and cause chronic inflammation of the conjunctiva and limbus, resulting in initiation and progression of pterygium. Recent evidence suggests that potentially oncogenic viruses such as human papillomavirus and Epstein-Barr virus may be involved in the pathogenesis of pterygia [25]. Infection might be related to activation of the alternative pathway (CFH) and the lectin pathways (C2 and MASP1) in the pathogenesis of pterygium.…”

Investigation of the Possible Association between Human Cytomegalovirus and Pterygium Development

“…2. Given the ubiquitous nature of HCMV, one can speculate that the IE1 and IE2 gene products might be mutagenic and cooperate/interact with other viral oncoproteins including adenovirus E1A and E1B, HPV E6 and E7, or even tumor necrosis factor in fibroblasts, smooth muscle cells or endothelial cells in order to block apoptosis or to transform cells (11,(18)(19)(20)…”