Why is it crucial to find a new approach to contraception ?

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, some women cannot take pills because of cardiovascular problems and family history.

Despite the huge progress made for contraception since the beginning of the 20th century, contraception still needs improvement.

We want to use microbicide with a spermicidal effect as a new way of contraception: safe and affordable, with a long term effect.

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 L. 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 “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 some of them such as Nisin, Subtilosin ... (for more information : Description of the projet). The idea is to introduce the genes that are coding the spermicidal peptids and antibodies into Lactobacillus jensenii and then to apply a colony of these designed bacteria into the vagina for long-term contraception.

Lactobacillus jensenii : a little-known bacteria

Lactobacillus jensenii is a little studied bacteria. We can find it in the vagina (23% of vaginal microflora), on the skins of grapes at the time of their harvest. Moreover, in the industry L. jensenii is sometimes used in producing fermented foods.

A part of our project is to establish a toolbox of L. jensenii by integrating experiments, bioinformatic tools and modelisation. Indeed L. jensenii is essential for the vagina health. We hope that a better knowledge of this bacterium, essential to the proper functioning of the female genital tract, will help a better understanding of certain diseases such as fungal and urinary tract infections.