Dr Fani Papagiannouli, a Lecturer in Biological Sciences and the School Director of Graduate Research Studies at the Medway School of Pharmacy has discovered that cells that give rise to sperm don’t just receive guidance signals on how to change, from the regular cells surrounding them, but both cell types are actually in a continuous dialogue with each other. The work was recently published in Stem Cell Reports, which is the official journal of the International Society for Stem Cell Research (ISSCR).
Understanding more about this process can help us to learn more about fertility in humans. The study was conducted in Drosophila flies. They are commonly known as fruit flies and are often used in research due to their genetic similarity to humans.
Spermatogenesis is the process by which specialised cells, called germ cells, give rise to sperm in the testes, while somatic cells (that normally build our body structures) wrap around and guide the germ cells through this process. Somatic and germ cells send signals to each other, and it was previously thought it was always one of the two that lead this communication.
Dr Papagiannouli has found that cells are in a dialogue that is more dynamic than initially thought - the somatic cells send a signal to germ cells to initiate change to create sperm, and the germ cells signal back causing somatic cells to change in their response as well. This continues back and forth is a dialogue of “equal partners”.
Somatic cells can have different shapes and the ones that wrap around germ cells are flat and elongated and called squamous cells. A pair of squamous somatic cells wrap around the germ cells they support, creating an egg-like shaped 3D structure within the testes.
If squamous somatic cells lose their elongated shape, become round and cannot wrap around the germ cells, cell-to-cell communication fails. This means sperm is not produced and therefore the organism is infertile, so this research could aid greater understanding of infertility.
Dr Papagiannouli and the team hope now to understand how these somatic cells acquire their specialised shape and how this affects the production of fertile sperm.
As flat squamous somatic cells line body surfaces and internal organs in humans as well, understanding their importance and function could also help us understand what goes wrong in squamous carcinomas too, a type of cancer that originates in human squamous cells.
Studying squamous cells had previously proved challenging with traditional techniques, because of limitations linked to their specialised thin shape. Dr Papagiannouli has received the #Springboard25 award from the Academy of Medical Sciences (AMS) following this research. It will support her team to tackle the key questions on squamous cells, using advanced electron-microscopy and proteomic techniques.
Dr Papagiannouli says:
“We are very enthusiastic with our new findings on the dynamics of cell-to-cell communication and excited as the AMS funding will enable us to learn more on the “modus operandi” of squamous cells at a mechanistic level, in Drosophila and beyond, by uncovering mechanisms shared with other organisms.”
