Genomic Analysis of E1A and E1B Regions of Human Adenovirus Type 8 in Patients with Adenoviral Keratoconjunctivitis in Ahvaz City

Epidemic Keratoconjunctivitis is an acute ocular infectious disorder often associated with Human Adenovirus Type D8 (HAdV-D8). E1A and E1B are adenoviral proteins that play a crucial role in initiating adenoviral infection and binding to cellular p53. This study aimed to analyze genomic diversity in E1A and HAdV-D8 E1B genes in patients with adenoviral Keratoconjunctivitis.

Samples of 5 patients with adenoviral Keratoconjunctivitis were cultured on A549 cell line for 48 to 72 hours until the appearance of CPE. The E1 gene region was amplified by PCR and sequenced to investigate mutations.

The Ahvaz strain showed the highest similarity to Japanese and American HAdV-D8 and HAdV-D54 strains in E1A and E1B genes. No significant mutation was found in the E1A gene. However, in the E1B gene, an amino acid substitution of serine to phenylalanine occurred. Another mutation converting CTG to GTG in E1B 55KD was observed only in two samples. The analysis with BLOSUM62 matrix confirmed that the replacement of valine with leucine is more likely than the substitution of serine and phenylalanine, which have hydrophobic properties and higher molecular weight.

In this study, E1A and E1B gene sequences of HAdV-D8 strain exhibited high conservation. Investigating these strains and their mutations in the human population could be valuable for determining the evolutionary capacity and pathogenicity of the virus.