THE UNKNOWN ROLE OF THE VIROME IN OUR SKIN
With the overwhelming entry into our lives of the word virus in early 2020, its presence has been normalized. It is seen as a tiny element capable of upending our lives, changing lifestyles, and even causing a global crisis.
But despite its low reputation now, the word virus does not always have to be linked to disease and crisis but surprisingly it can also be something beneficial.
In recent years, there has been extensive talk of the skin microbiome. Microbiota is not the same as microbiome; the first refers to the set of microorganisms that reside in our body, among other locations our skin; while the microbiome, a broader term, includes the genetic material and metabolites generated by these microorganisms under specific environmental conditions. We could define it as a microbial ecosystem, which, over time, has demonstrated its importance in countless pathologies. However, less well known is that healthy humans are also colonized by a remarkable diversity of viruses — the virome.
Similarly to the skin microbiome, the skin virome is composed of both resident and transient viruses. They can be commensal, pathogenic or that can become so, transient or phages (viruses that infect bacteria). Several studies have described that there is interindividual and even temporal variability in the genetic diversity derived from viruses. The most common viruses are those of the families of Papilomaviridae (up to 17 different strains in the same individual), Polyomaviridae and Circoviridae. Infection by a virus will occur if it can invade a tissue and also evade the immune system. However, it is important to note that viruses need the production of proteins by the host to be able to replicate.
The components of the skin barrier are the microbiome (and virome) barrier, the chemical barrier (lipids, pH, NMF, antimicrobial peptides, antiviral proteins…), the physical barrier (formed by skin cells) and the immune barrier. Despite all this, a compromised skin barrier function due to exacerbating factors such as UV radiation can cause viruses resident in our skin to trigger diseases, as in the case of the herpes simplex virus.
Other data reflecting the importance of the virome are found in a study comparing the virome of healthy and atopic dermatitis subjects. Those who present atopic dermatitis (on seemingly healthy skin) differ in their virome, as the population of papillomavirus and bacteriophages is increased compared to those with healthy skin.
Another known fact is that bacteriophages are viruses (those of the virome also) that have a very specific infectious mode of action since they have the ability to eliminate bacteria. Currently, bacteriophages and the endolysins they produce are used to treat pathologies such as acne or atopic dermatitis.
Although the virus commensal role in our skin is quite unknown, there are interactions that modulate or facilitate the development, or not, of pathologies.
In two years from now, at the 33rd IFSCC Congress in Barcelona, the virome paradigm may have changed enormously, and perhaps we can better understand the role of viruses in our body, and especially important for our sector, the skin virome. We’d like to encourage you to take the opportunity to present your research around this or any other cutting-edge topic.
References
Deciphering the microbiome and virome composition of patients with Atopic Dermatitis and Eczema Herpeticum (ADEH+), Journal of Allergy and Clinical Immunology. February 2019
Marc Lecuit, Marc Eloit. The human virome: new tools and concepts. Trends Microbiol. 2013 Oct; 21(10): 510–515.
Guanxiang Liang, Frederic D. Bushman. The human virome: assembly, composition and host interactions Nature Reviews Microbiology, volume 19, pages 514–527 (2021)
Zaramela, L.S, Belgini D. , Ramirez- Gama M.A, Johnson K. Deciphering the microbiome and virome composition of patient with atopic dermatitis and Eczema Herpeticum. Journal of allergy and clinical inmunology, February 2019