Human Aqueous Humor Levels of TGF-β2: Relationship with Axial Length

PURPOSE To analyze the relationship between transforming growth factor-beta 2 (TGF- β 2) levels in the anterior chamber aqueous humor and axial length of patients with myopia. METHODS TGF- β 2 was measured with the Luminex xMAP Technology by using commercially available Milliplex xMAP Kits. Sixty-five aqueous humor samples were collected during cataract or clear lens extraction surgery and TGF- β 2 levels in these specimens were analyzed. According to the axial length, the samples were divided into three groups: A (AL ≤ 24 mm), B (24 ~ 29 mm), and C (AL ≥ 29 mm). RESULTS Aqueous humor samples were analyzed from subjects with an average age of 67.0 ± 11.7 years. Mean TGF- β 2 concentration of all aqueous samples was 422.2 ± 258.8 pg/mL. TGF- β 2 concentration in group C (543 ± 317 pg/mL) was significantly greater than that in group A (390 ± 212 pg/mL) and group B (337 ± 217 pg/mL). The concentration of TGF- β 2 was positively correlated with axial length (r = 0.308, P = 0.013). CONCLUSIONS TGF- β 2 is likely to be acting as a critical factor in axial elongation and development of myopia.