Team:Montpellier
Why is it crucial to find a new approach to contraception?
Despite the huge progress made for contraception since the beginning of the 20th century contraception still needs improvment. Hormonal contraception has a lot of side effects for women (such as weight gain or acne), a pill is easy to forget, and there is an environmental impact since water can be contaminated by hormones.
Moreover, it has been shown that it’s difficult for women to negotiate the use of condoms with their partners (which is the only method to prevent STD infections and another common method to avoid unwanted pregnancies). Microbicide can allow a new way of contraception: safe and affordable, where women don’t have to negotiate with their partners.
How do we do that ?
We decided to focus on making a new kind of contraceptive using Lactobacillus jensenii, which is one of the most represented bacteria in the vaginal flora. This hormone-free contraception uses a designed Lactobacillus jensenii that has the ability to immobilize spermatozoa in the vagina.
How does it really work? Our goal is to create bacteria capable of having a “light switch effect”. When a woman decides to turn it on, bacteria will have a spermicidal effect and will allow in situ contraception. Otherwise, bacteria will be in “off mode”, and spermatozoa will be able to pass.
Several studies have demonstrated that many molecules have spermicidal activity, we are focusing on :
| Name | Type of molecule | Origin |
|---|---|---|
| Nisin | Lantipeptid | Lactococcus lactis |
| Lacticin 3147 | Lantipeptid | Lactococcus lactis |
| Subtilosin A | Sactipeptid | Bacillus subtilis |
| Magainin II | Magainin | Xenopus laevis |
| LL37 | Cathelicidin antimicrobial peptid | Homo sapiens |
| YLP20 | Anti bodies | Homo sapiens |
| AS16 | Anti bodies | Homo sapiens |
The idea is to introduce the genes that are coding for the spermicidal peptids and anti bodies into Lactobacillus jensenii and then to apply a colony of these designed bacteria into the vagina for long-term contraception. When a woman wants to remove this contraceptive device, we would like to put a switch off mecanism.
