Transforming growth factor-β₂ gene cloning and protein expression in human trabecular meshwork cells

Abstract

Whether cultured human trabecular meshwork cells express transforming growth factor-β₂ (TGF-β₂) messenger RNA (mRNA) and protein was investigated. Total RNA of 10⁶ cultured human trabecular meshwork cells was extracted with TRIZOL reagent, reverse transcriptase-polymerase chain reaction (RT-PCR) were used for detection of TGF-β₂ messenger RNA, and the PCR product was verified by sequencing. Immunohistochemical staining was used to detect TGF-β₂ protein. The results showed that a single RT-PCR amplified product was obtained, and the sequence was homologous to the known sequence. TGF-β₂ immunostaining was positive. It was concluded that trabecular meshwork cells could produce TGF-β₂ and contribute to the presence of TGF-β₂ in trabecular meshwork microenvironment as well as aqueous humor. Trabecular meshwork cells were affected by TGF-β₂ not only through paracrine, but also autocrine action. Whether abnormal changes in TGF-β₂ production contribute to the pathogenesis of primary open-angle glaucoma is worth further investigation.

Keywords

human / trabecular meshwork / cultured cells / transforming growth factor / reverse transcriptase-polymerase chain reaction / immunohistochemistry

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