A team of researchers announced on Apr. 3 the development of an immune-capable "organ-on-a-chip" model that closely replicates the human cervical environment, enabling new studies into sexually transmitted infections (STIs). The research was conducted by scientists from the University of Maryland School of Medicine and School of Dentistry, the University of Delaware, and the University of Virginia, and published in Science Advances.
This advancement is significant because STIs not only affect individual health but also cause substantial economic losses worldwide. Chlamydia and gonorrhea are among the most common STIs, with combined direct medical costs estimated at around $1 billion annually in the United States. According to global estimates from the World Health Organization, nearly one million new STI cases occur daily among people aged 15 to 49.
The newly developed organ-on-a-chip system—also known as a microphysiological system—uses layers of human cervical cells, supportive tissue cells, immune cells, fluid flow, and microbiomes typically found in the vagina. This setup allows for more accurate simulation of physiological conditions compared to traditional cell cultures or animal models.
Co-lead author Jason Gleghorn said: "A key goal was to develop a complex model system that is both practical and accessible, enabling researchers outside of bioengineering labs to adopt it and apply it to answer important biological questions." He added that understanding how different vaginal microbiomes influence susceptibility to STIs was a critical need addressed by this new model.
Testing with chlamydia and gonorrhea showed that protective microbiomes dominated by Lactobacillus crispatus limited infection within the model. Dr. Ravel said: "One of the most exciting findings was that just like in women, protective microbiomes dominated by Lactobacillus crispatus limited infection in the model, highlighting further the critical role of the vaginal microbiome in STI risk. In contrast, when we introduced 'nonoptimal' microbiomes, infections worsened." Ravel continued: "This model provides a powerful new tool to develop faster, more effective, and personalized treatments... For the first time we can simulate what happens in the human body rather than relying solely on petri dish systems or inadequate animal models."
