Brigitte Pasteels

Calbindin and calretinin localization in retina from different species

Calbindin-D28K and calretinin are homologous calcium-binding proteins localized in many neurons of the central nervous systems. We have compared polyclonal antibodies against calbindin and calretinin and have shown by western blots using purified calbindin and calretinin from rat that (1) anti-calretinin does not recognize calbindin and (2) anti-calbindin presents some cross-reactivity with calretinin. In this report, we have compared by immunohistochemistry the localization of both calcium-binding proteins in the retina of monkey, pig, sheep, rat, cat, pigeon, and salamander. These results are compared with previous data for chick. There are many differences between species and not within species, but some aspects of the distribution are conserved. All species, except rat and monkey, have some cones which contain calbindin only. Most species also have some bipolar cells containing calbindin only. Calretinin is rarely seen in photoreceptors or bipolar cells. All species have horizontal cells which contain calretinin or calbindin or both. All species have amacrine cells and ganglion cells containing one or other protein. In the cat ganglion cell layer, the calretinin antisera define a new, asymmetric, type of cell.

Calbindin-D28 in Mammalian Brain, Retina, and Endocrine Pancreas: Immunohistochemical Comparison with Calretinin

Calbindin 28K and calretinin are very similar calcium binding proteins which are both present in the central nervous system (CNS). They respectively bind 4 and 5 Ca++ ions. We have compared by immunohistochemistry and in situ hybridization their localisation in the brain and the retina. The two proteins are generally expressed in different neurons with a few neurons containing both calcium binding proteins. Calbindin 28K is also present in the endocrine system. We have examined the cellular distribution of calbindin in the pancreatic endocrine cells of chick, rat and human and found variable distribution among the different endocrine cell types. We also describe the presence of calbindin in RINm5F cells, an insulin-producing tumor cell line derived from a radiation-induced rat insulinoma.

Photodynamic therapy for subfoveal classic choroidal neovascularization related to punctate inner choroidopathy (PIC) or presumed ocular histoplasmosis-like syndrome (POHS-like)

Purpose: To evaluate the safety and efficacy of photodynamic therapy with verteporfin (PDT) for subfoveal classic choroidal neovascularization (CNV) related to punctate inner choroidopathy (PIC) or presumed ocular histoplasmosis-like syndrome (POHS-like). Methods: Retrospective review of 16 eyes from 14 patients with subfoveal classic CNV associated with PIC or POHS-like and treated with PDT. Results: The mean visual acuity increased from 4.5/10 (range: 1/10–9/10) to 7/10 (range: 2/10-10/10) after a mean follow-up of 21 months (range: 8–32 months) and a mean number of 2 PDT (range: 1–6). Visual acuity remained stable or improved in 13 of the 16 eyes (81%) and decreased in three. Conclusion: This nearly two-year follow-up study suggests that PDT could be helpful for patients with subfoveal classic CNV related to PIC or POHS-like.

Pineal-retinal molecular relationships; immunocytochemical evidence of calbindin-27 kDa in pineal transducers

Calbindin-27 kDa immunocytochemical localization was studied concurrently in the pineal organ and retina from human as well as representatives of all vertebrate classes. Calbindin immunoreactivity was demonstrated in retinal cones (but not in rods) and in pineal transducers (cone-like and modified photoreceptor cells, pinealocytes) of a majority of amniotes. In contrast, no labelling was observed in anamniotes, except in retinal cones of the toad. Labelling was distributed through all cellular compartments (outer and inner segments, perikarya, pedicles or processes) of pineal transducers and retinal cones. Intra- and interspecific variations of calbindin contents are discussed.