What is skin microbiota?
Skin microbiota is an ecosystem inhabited by a community of more than a million microorganisms (bacteria, viruses, fungi) per square centimeter of skin.
Bacterial composition of skin (cutaneous microbiota) is mostly dominated by the following genera: Propionibacteria (23%), Corynebacteria (22.8%) and staphylococci (16.8%).
Most of the bacteria in epidermis are “commensal” and live in a symbiotic manner with the host that they colonize.
Interactions between the host immune system and its microbiota contribute to the control of the skin bacterial composition as well as to the education of the adaptive immune system of the host.
Imbalance in the microbiota composition can cause skin disorders (dry skin, oily skin, dandruff, etc.) and pathologies (psoriasis, atopic dermatitis, acne, etc.).
Skin microbiota: available models and assays
Thanks to its expertise in cellular and tissue engineering, QIMA Life Sciences has developed in vitro or ex vivo study models that are suitable for analyzing the interactions between microbiota and skin:
- Isolated bacterial culture (Staphylococcus aureus, Staphylococcus epidermidis, Cutibacterium acnes, Corynebacterium xerosis …)
- bacteria on 2D skin models (keratinocytes, fibroblasts, sebocytes, etc.)
- bacteria on 3D skin models (reconstructed epidermis, etc.)
- Infection experiments with the HSV-1 virus ( Herpes simplex virus type I)
Both the impact of compounds or formulations on the development of bacteria and the influence of bacteria on cutaneous response can be assessed by these models.
QIMA Life Sciences offers a panel of solutions for the evaluation of:
- Bacterial viability
- Quantification of bacterial colony (CFU)
- Determination of bacterial load (qPCR (Taqman))
- Bacterial adhesion on 3D models (reconstucted epidermis) – quantification of colony, qPCR, radioactivity, SEM
- Biological response of 2D or 3D models (differentiation, inflammation and immune response)
QIMA Life Sciences provides a wide range of microorganisms tested by our laboratory and available for in vitro testing:
GRAM (+) :
- Staphylococcus aureus
- Staphylococcus epidermidis
- Cutibacterium acnes
- Corynebacterium xerosis
- Streptococcus pyogenes
- Mix of several strains (upon request)
- Other strains upon request
GRAM (-) :
- Pseudomonas aeruginosa
- Other strains upon request
- Herpes simplex virus type 1 (HSV-1)
- Human Rhinovirus 16 (HRV-16)
Here are a few examples among all standard assays proposed by QIMA Life Sciences in the field of skin microbiota:
Skin microbiota analysis
Our company has developed ready-to-use non-invasive collection kits to analyze the lipids and biomarkers of the skin surface from your samples or from those of your clinical center.
The qualitative and quantitative analysis of the bacteria present on the surface of the skin are carried out on samples with the SW Kit. They are performed using the following techniques:
- Traditional microbiology on agar
- Targeted qPCR
- Non-targeted metagenomic analysis
In addition, the analysis of sebaceous lipids (triglycerides and fatty acids) gives information on the lipase activities of bacteria and yeasts such as C. acnes and M. furfur, involved in the development of acne and dandruff respectively.
These evaluations help support your claims about the efficacy of “friendly” microbiota products, bacteriostats, antimicrobials, prebiotics, anti-acne products, anti-dandruff products, etc.
Data mapping and clinical imaging
Measurement of porphyrin fluorescence in UV imaging
Acne-prone skin can present a high fluorescence rate under UV, due to the metabolism of the bacteria specific to acne. The measurement of porphyrin fluorescence intensity is therefore a marker of the evolution of the inflammatory and bacterial skin condition.
Measurement of skin fluorescence on image acquired with ColorFace ®
The Relationship Between Microbiology Testing and the Skin MicrobiotaCosmetics, Skin microbiome
Microbiology testing is essential for substantiating microbiome-friendly and anti-microbial claims. Read on to find out how cosmetic microbiology testing is connected to the skin microbiome.
Microbiota vs. Microbiome: What’s the Difference?Skin microbiome
What is the difference between microbiota vs. microbiome? Why are they important to human skin? What is the Skin Microbiota test? Learn more here.
Using Reconstructed Human Epidermis model in Skin Microbiome ResearchSkin microbiome, Skin microbiome
Skin microbiome research is developing rapidly. Are you up to date? Find out why 3D skin models are an important development in skin microbiome research.
Profiling TLR agonist activity in keratinocytes and link to bacteria-induced innate immunity activationCosmetics, Microbiome cutané, Skin microbiome
In this study, our goal was first to functionally profile and characterize the response of normal human keratinocytes (NHEK) to microbial patterns (TLR agonists) and IL-1α in parallel. To do so, the effects of multiple TLR agonists and IL-1α were evaluated on the gene expression profile, on signal transduction (NF-ƘB translocation) and also on IL-8 and IL-6 release. Secondly, we also tried to link these responses to those of pathogens of interest in skin microbiota (namely, C. acnes, S. aureus and P. aeruginosa), by evaluating the effect on IL-8 release by NHEK infected with living bacteria from these 3 strains…