Polarized light microscope enabled breakthrough stem cell production in monkeysNovember 30th, 2007 - 6:03 pm ICT by admin
London, November 30 (ANI): Researchers at Oregon Health & Science University have revealed that a non-invasive imaging system played a very significant role in their recent research, which led to the production of stem cells from cloned monkey embryos.
Lead researcher Dr. Shoukhrat Mitalipov said that his project involved a polarized light microscope called Oosight microscope, invented at the Marine Biological Laboratory (MBL).
A faction of researchers had claimed in recent years that it would be technically impossible to make embryonic stem cellswhich can be induced to become any type of cell, tissue or organfrom monkeys or humans using the method called somatic cell nuclear transfer, or therapeutic cloning.
However, Mitalipov said that his team had successfully adapted the Oosight microscope system, developed by Cambridge Research & Instrumentation Inc. (CRi), for somatic cell nuclear transfer and embryology.
The use of the Oosight was one of the major modifications we made in our present work, Nature magazine quoted him as saying.
He revealed that the technology enabled his team to clearly see and remove the meiotic spindle (and the attached genetic material) from 304 female rhesus monkey eggs, which was the first step in therapeutic cloning called enucleation.
The research team then inserted the genetic material from the skin cells of an adult male rhesus monkey into the eggs, and allowed them to grow to the blastocyst stage. Thereafter, two viable stem cell lines, genetically identical to the adult male monkeys, were derived from the cloned embryos.
Mitalipov says that the Oosight uses liquid-crystal polarized light technology to image the spindle non-invasively, with high contrast and quality.
Before, the problem was always that you could not see the spindle in the egg. The only way to see it was to stain it with dyes. And that, we found, was very detrimental for egg quality, he says.
You can actually look in the Oosight microscope and see the spindle with your eyes, not frozen as a computer screen image, he says.
Mitalipov insists that the ability to see the spindle with the eyes is critical to taking the spindle out of the egg.
You cant manipulate the egg while looking at a computer screen. You have to look at the egg. The Oosight, plus very skilled micromanipulations of the eggs, gave us a 100 per cent success rate with enucleating, he says.
Mitalipov believes that his method for deriving stem cells is a potential way to make custom tissues that are genetically identical to a patient, which would avoid rejection by the patients immune system. (ANI)