New Biomarker for Neovascular Age-Related Macular Degeneration: Eotaxin-2 Neel Kamal Sharma, 1 Sudesh Prabhakar, 1 Amod Gupta, 2 Ramandeep Singh, 2 Pawan Kumar Gupta, 1 Pramod Kumar Gupta, 3 and Akshay Anand 1 Recently, eotaxin–CCR3 was reported to play an important role in choroidal neovascularization (CNV) devel- opment and was documented to be superior than vascular endothelial growth factor-A treatment when tested in CNV animals. As eotaxin studies are lacking in the human age-related macular degeneration (AMD) patients, we sought to determine whether eotaxin-2 (CCL24) has any association with inflammatory processes that occur in CNV. CCL24 levels were determined by enzyme linked immunosorbant assay (ELISA) after normalization to total serum protein and levels of ELISA were correlated to various risk factors in about 133 AMD patients and 80 healthy controls. The CCL24 levels were significantly higher in wet AMD patients as compared with dry AMD and normal controls. There was a significant difference when compared among wet AMD patients (i.e., mini- mally classic, predominantly classic, and occult). We also report significant difference in the CCL24 levels of Avastin-treated and untreated AMD patients. This study shows that CCL24 levels were found to be significantly increased in AMD patients despite Avastin treatment as compared with normal controls and those without Avastin, indicating that CCL24 may have an association with CNV and may be an important target to validate future therapeutic approaches in AMD in tandem with Avastin treatment. Introduction A ge-related macular degeneration (AMD) is among the commonest causes of blindness across the world. There are about 30–50 million people affected globally in which 90% of vision loss is due to wet form of AMD (Ambati et al., 2003). It is estimated that by 2020 about 2.95 million people in the United States will have advanced AMD and data on AMD in India show that prevalence from 2.7% (early age related macular degeneration [ARMD]) to 0.6% (late ARMD) in South India to 4.7% in North India (Azad et al., 2007). The pathogenesis of AMD is complex and many risk factors, such as age, family history, and smoking, have ear- lier been implicated in the pathogenesis of AMD. The wet AMD is the severe form of disease causing blindness while the dry form is the milder variant characterized by geo- graphic atrophy. Earlier studies in genetics, environment, and demography association have failed to conclusively es- tablish any potential predictor of AMD. Besides, very few studies have been conducted in Indian subcontinent. Cur- rently, there is no treatment for this disease and successful targeting of abnormal choroidal neovascularization (CNV) remains critical in reducing the burden of disease. One of the standard treatments in opthalmology practice includes the use of anti-vascular endothelial growth factor (anti-VEGF) therapy, such as Avastin (bevacizumab) or Lucentis (ranibi- zumab). Anti-VEGF that constitutes these drugs have, therefore, emerged as one of the treatments for patients with CNV but this does not completely treat AMD with only about one-third of patients are believed to benefit from it. Early diagnosis and better cure of CNV may increase the success rate of such intervention. There are many human and animal studies that have reported the role of various genes responsible for AMD. Many multiple genetic studies have established the role of inflammation in AMD. For example, CFH gene is involved in the complement pathway; the complement component 2 gene and the complement factor B gene have repetitively been associated with AMD (Maller et al., 2006). It is believed that complement activation re- sulting from dysfunction of these genes may contribute to inflammatory response. In the infiltration of monocytes for inflammation, CCL2 and CCR2 are the key mediators. We previously described the spontaneous development of CNV in senescent mice deficient in monocyte chemoattractant protein-1 (CCL2, also known as MCP-1) or its receptor pos- tulating its key role in AMD pathogenesis (Ambati et al., 2003b). CCL2 thus plays an important role in regulating monocyte trafficking to sites of inflammation besides CCR1, CFH, and CCR5 whose association with eotaxin 2 (CCL24) has not been adequately studied. The eotaxins are a family of 1 Department of Neurology, 2 Department of Ophthalmology, and 3 Department of Biostatistics, Postgraduate Institute of Medical Education and Research (PGIMER), Chandigarh, India. DNA AND CELL BIOLOGY Volume 31, Number 11, 2012 ª Mary Ann Liebert, Inc. Pp. 1618–1627 DOI: 10.1089/dna.2012.1786 1618