its ability to stimulate the immune system to attack cancer cells<\/a>. CPMV has shown strong anti-tumor effects in preclinical mouse models and in clinical studies in canine cancer patients.<\/p>\nTo make CPMV, Steinmetz\u2019s team uses Nicotiana benthamiana and black-eyed pea plants. \u201cGrowing the compound in these plants is simple,\u201d said study first author Patrick Opdensteinen, a postdoctoral researcher in Steinmetz\u2019s lab. \u201cThey can produce a whole lot of biomass in a short amount of time, and more biomass equals more product. The main difficulty now is figuring out how to get the product out of the plants.\u201d<\/p>\n
Extracting CPMV \u2014 and other pharmaceutical products \u2014 from plants typically involves picking the leaves and grinding them in a blender. \u201cYou end up with something that looks like a smoothie, and you can imagine getting your product out of that smoothie is challenging,\u201d Opdensteinen said. \u201cThe equipment that we use to do this fills our entire lab. You can\u2019t fit all that on a spacecraft.\u201d<\/p>\n
The new study focused on simplifying that step.<\/p>\n
The team was inspired by an approach used with bacterial and mammalian cells in pharmaceutical manufacturing: product secretion. \u201cBasically, the product comes out of these cells,\u201d Opdensteinen said. \u201cThis is possible in plants, too.\u201d Plants secrete products into a compartment inside the leaves called the apoplast, which is a network of interconnected spaces outside of the plasma membrane.<\/p>\n
The researchers found that they can draw CPMV out of the apoplast while keeping the leaves intact. First, the leaves are submerged in a buffer solution and placed in a sealed vessel. Vacuum is applied, which floods the apoplast with fluid. The saturated leaves are then placed in vials and gently spun in a centrifuge to draw the liquid \u2014 which contains CPMV particles \u2014 back out. The resulting liquid is purified through a filter that separates the larger CPMV particles from smaller unwanted plant material.<\/p>\n
The method is easy to scale up. Researchers were able to harvest and purify CPMV particles from more than 50 plants in under two hours. And because the leaves remain intact, the plants can continue to grow and potentially be harvested over and over again. The team envisions adapting the process to entire living plants rather than just the leaves.<\/p>\n
Testing Drug Production in Space Conditions<\/p>\n
The team also tested the method on plants grown under simulated space conditions.<\/p>\n
To mimic microgravity, Steinmetz\u2019s lab collaborated with the lab of Maziar Ghazinejad, professor in the Department of Mechanical and Aerospace Engineering at the UC San Diego Jacobs School of Engineering, to custom build a random positioning machine, which continually rotates the plants to effectively cancel out gravity. Ghazinejad\u2019s lab normally uses these machines to study how materials would behave in space. Steinmetz and Ghazinejad saw an opportunity to adapt this approach for plant studies.<\/p>\n
The plants were also exposed to temperature fluctuations and oxidative stress to mimic the effects of space radiation. In some cases, the stressors slightly increased CPMV yields. The researchers hypothesize that the effect may be linked to the nature of CPMV as a plant virus. \u201cPlants become more susceptible to disease when stressed, which is usually a disadvantage,\u201d Opdensteinen said. \u201cBut since our product is derived from a plant virus, we can use that stress response to increase yields.\u201d<\/p>\n
The team\u2019s ultimate goal is to have their method tested on actual space missions. Before that can happen, the team still has more work ahead. They will continue studying how space conditions affect plant processes such as water and nutrient uptake. They will also be working with the Rocket Propulsion Laboratory at UC San Diego to test how rocket launches affect plant seeds and the genetic materials used in the process.<\/p>\n
Full study: \u201cStreamlined molecular farming of plant virus therapeutics for space flight and other low-resource environments\u201d<\/p>\n
This work was supported in part by the National Institutes of Health (grant R01CA274640) and the Translational Research Institute for Space Health (TRISH) through NASA Cooperative Agreement NNX16AO69A.<\/p>\n
Disclosures: Nicole Steinmetz is a co-founder and CEO of, and has equity in, PlantiosX Inc. Steinmetz is a co-founder of and has equity in Mosaic ImmunoEngineering Inc. Steinmetz is a co-founder and manager of Pokometz Scientific LLC, under which she is a paid consultant to Ring Therapeutics, Inc. The other authors declare no potential COI.<\/p>\n","protected":false},"excerpt":{"rendered":"Astronauts on long space missions may one day use plants to produce fresh stocks of medicines on demand,…\n","protected":false},"author":2,"featured_media":478839,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[985,19050,85,46,983,141,222084,24616],"class_list":["post-478838","post","type-post","status-publish","format-standard","has-post-thumbnail","category-science","tag-all-journal-news","tag-grant-funded-news","tag-il","tag-israel","tag-newswise","tag-science","tag-space-medicineplant-virusesplant-virusspace-researchnanomedicinepharmaceutical-manufacturingplant-products","tag-university-of-california-san-diego"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/posts\/478838","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/comments?post=478838"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/posts\/478838\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/media\/478839"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/media?parent=478838"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/categories?post=478838"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/il\/wp-json\/wp\/v2\/tags?post=478838"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}