Protein profiles of microsections of the fetal and adult human lens during development and ageing

The water-soluble proteins of the human fetal lens (175- and 285-day-old) contain HM-, pre-α, α-, β- and γ-crystallins. Using the frozen-sectioning technique, it can be demonstrated that the fetal lens does not have a homogeneous distribution of crystallins, but there are gradual differences between the cortices and the nucleus. The frozen-sectioning technique shows for the adult lens significantly increasing amounts of β-crystallins of pI 4.95–5.5, especially at the posterior supra-nuclear layer, increasing amounts of HM-crystalins and decreasing amounts of β-crystallins of pI 5.80–7.05 in the nucleus. This microsectioning technique was correlated with Scheimpflug photographs of the fetal and adult lens. In the fetal lens, the anterior capsule and 2 peaks in the anterior and posterior supranuclear layers could be visualized after densitometry. In the adult lens 5 layers could be demonstrated, e.g. the anterior capsule, the anterior supranuclear layer, the nucleus, the posterior supranuclear layer and the anterior capsule.