Investigations in Intravitreal AAV Gene Therapies

Article: Improved vectors for ocular gene therapy
Source: University of Munich, via ScienceDaily  and Technology Networks
Published: February 22, 2021

This is an interesting study as a follow up to the article about AAV gene therapies by researchers at the Wyss Institute at Harvard University, as this study also addresses the topic of AAV gene therapy, in this case with a focus on intravitreal injection. As with the Wyss Institute study, the researchers note the limitations of subretinal injection, which prompted further investigation of vector delivery intravitreally. The news article itself is short, and the only section that discusses methods states, "Further studies on three animal models [mice, dogs and non‐human primates] confirmed the efficacy of the procedure, and experiments on human retinal tissue grown in culture confirmed that the vectors can infect photoreceptors and other retinal cells. Finally, initial results of experiments on a mouse model of achromatopsia (complete lack of color vision) suggested that the procedure is capable of restoring some degree of daylight vision." With regard to intraocular inflammation, two of the five dogs used in the study developed inflammation events, which the researchers hypothesized was in response to the enhanced green fluorescent protein (eGFP) rather than the vector capsid, without detailed explanation. In either case, though a good addition to the archive of knowledge about intravitreal gene therapies, the study still shows that this method has not surmounted the obstacle of inflammation if vectors are delivered intravitreally. The approach would probably have been more novel had it been published prior to the study by the Wyss Institute.

Personal commentary: I know I get a bit of critique for including articles and research from lesser known (often international) universities in this archive, for example, comparing research by the University of Munich alongside that of Harvard. The blog is not only for dissemination of information, but also for my own practice in seeing it and examining it. This is why it is a review and why I include my own ratings of the studies. I am aware that research funded by the NEI, for example, is much more robust. But I see no harm in reviewing research from lesser known sources.

My rating of this study: ⭐⭐

Further reading: Tool offers ultra-rapid cooling for intravitreal injections