CD44 and dry age related macular degeneration: Since oxidative stress is the underlying cause of dry AMD and one of the factors responsible for multifactorial wet AMD, we decided to study the effect of oxidative stress on CD44 expression in the RPE cells, so that it may be used as a suitable target during oxidative stress for receptor mediated selective drug delivery with a previously reported nucleic acid CD44 aptamer - specific for hyaluronic acid binding domain (HABD) of the CD44 protein [10].