Rabbit rubeosis iridis induced by intravitreal latex-derived angiogenic fraction

PURPOSE

To describe the presence of iris neovascularization in a rabbit-model of retinal neovascularization induced by the intravitreal injection of latex-derived angiogenic fraction microspheres (LAF).

MATERIALS AND METHODS

Eight New Zealand rabbits received one intravitreal injection of PLGA (L-lactide-co-glycolide) microspheres with 50 ug of LAF in the right eye (Group A). Microspheres without the LAF (0.1 ml) were injected in controls (Group B; n = 8). Follow-up with clinical evaluation and iris fluorescein angiography was performed after 4 weeks when eyes were processed for light microscopy.

RESULTS

All eyes from Group A showed significant vascular dilation, conjunctival hyperemia and neovascularization on the iris surface, after LAF injection. No vascular changes were observed in Group B.

CONCLUSIONS

The intravitreal injection of microspheres containing the LAF can induce rubeosis iridis in rabbits and could be used as a simple experimental model for iris neovascularization.

A simple and reproducible method to obtain large numbers of axenic amastigotes of different Leishmania species

This work describes a simple method to yield large amounts of Leishmania amastigote-like forms in axenic cultures using promastigotes as the starting population. The method described induced extracellular amastigote transformation of Leishmania amazonensis (97%), Leishmania braziliensis (98%) and Leishmania chagasi (90%). The rounded parasites obtained in axenic cultures were morphologically similar, even at the ultrastructural level, to intracellular amastigotes. Moreover, the axenic amastigotes remained viable as measured by their ability to revert back to promastigotes and to infect BALB/c mice. L. amazonensis and L. braziliensis promastigotes and axenic amastigotes differed in terms of their Western blot profiles. A 46 kDa protein was recognized by specific antibodies only in axenic and lesion-derived L. amazonensis amastigotes and not in promastigotes.