Project information

Alopecia UK funds invested:  £10,000

When:  October 2020 - September 2022

Project type:  Clinical Research

Project Lead:  Dr Claire Higgins

Collaborators: Mrs Stephanie Moore, Miss Leen Batha.

Length of project: 2 years

Research Institute:  Imperial College, London

Conditions to be studied:  Female Pattern Hair Loss (FPHL), Male Pattern Hair Loss (MPHL), Telogen Effluvium (TE), Alopecia Areata (AA), Frontal Fibrosing Alopecia (FFA) and Lichen Planopilaris (LPP).

Funds being used for:  Consumables costs for microbiome analysis

Overall Aim of the Project:

To find out if there are differences in the scalp microbiome in different types of hair loss that can be used to identify the type of hair loss and are potential causes of that type of hair loss.

Justification for research project:

Dr Higgins plans to perform an in-depth analysis to determine the microbiome signatures of 6 different types of alopecia. They will use this to identify microbes which are generally characteristic of hair loss and distinguish these from microbes which are unique to a specific form of alopecia. Longer term, this data will be scrutinised to determine if the specific microbes are causative of hair loss, and if therapeutic intervention to alter the microbiome signatures can serve as a treatment for alopecia, and reverse hair loss.

Who is leading the project:

Dr Claire Higgins has a long-standing interest hair follicle development and disease. After conducting a PhD at the University of Durham (2003-2007) researching hair shedding, she did a postdoc in the Dermatology Department at Columbia University (2007-2013). Here, she researched various topics ranging from hair neogenesis for Androgenetic Alopecia, through to the genetic causes of Trichomegaly and Alopecia Areata. She was a co-author on the JAK inhibitors for Alopecia Areata story, which was published in Nature Medicine in 2014, changing the field of alopecia research. Since 2014 she has led her own research group (www.higginslab.org) in the Department of Bioengineering at Imperial College London, focusing on the response of the skin and hair follicle to perturbations in the form of physical trauma and disease. She is also the founder of the London Skin Club, a network to discuss and further scientific and clinical collaborations in hair and skin research.

What were the results? 

The researchers provided the following summary: 

"Our skin and hair is covered in hundreds of thousands of microbial communities, referred to as the skin microbiome. There is significant intra and inter person diversity within our microbiome. In particular, on the scalp, the sebaceous glands of the hair follicle create a lipid rich environment which means there is a lower microbial diversity there compared to dry or moist sites. The microbiota present on the skin produce antimicrobial peptides which help to maintain skin homeostasis. In skin conditions such as psoriasis and atopic dermatitis, several reports have documented how the skin microbiome diversity changes with disease. Specifically, in patients with psoriasis there is a reported increase in S.aureus and a decrease in S.epidermis – these changes are also associated with gut dysbiosis.

Five subcategories of alopecia consisting of alopecia areata (AA), androgenic alopecia (AGA), frontal fibrosing alopecia (FFA), lichen planopilaris (LPP) and telogen effluvium (TE) have been identified as priority research questions by the James Lind Priority Setting Partnership, as the mechanisms underlying their various aetiologies are still not yet fully understood. While alopecia itself is localised to the hair bearing scalp, several alopecia’s are associated with underlying endocrine and biochemical pathologies such as gut dysbiosis. We therefore hypothesised that the alopecias themselves would be associated with distinct microbiome signatures, which might explain the different pathologies. To address this, in this study we aimed to characterise the scalp microbiome in patients with different forms of alopecia. We selected both scarring and non-scarring alopecias, and set out to collect skin swabs (containing microbiota) from patients with AA, AGA, FFA, LPP and TE. Swabs of the scalp, from both lesional and non-lesional sites, were obtained from patients attending the Surrey Trichology Clinic for a consult about their alopecia. The study participants were given a patient information sheet about the study and gave written informed consent for a swab to be taken of their skin, for use in the study. Both the participant information sheet and consent form were approved by the Imperial College Research Ethics Committee. Swabs of the skin were then taken by running a swab (Q-Tip) 5 times over the alopecic area.

In total, we collected 84 swabs, from which bacterial DNA was isolated. This was then used for 16S sequencing, to characterise bacterial populations that were collected during the swabbing procedure. After quality control, we were left with 49 samples to analyse – 8 AA, 16 AGA, 8 FFA, 11 LPP and 6 TE.

Using this data, we were able to characterise the bacteria colonising the scalp at various taxonomic levels, from phyla down to species. As a brief overview of the phyla, we found that scarring alopecia (FFA and LPP) had significantly more Proteobacteria (p=0.00288) and Firmicutes (p=0.00042), and significantly less Actinobacteria (p=0.00288) compared to the non-scarring alopecias (AA, AGA and TE) (Figure 1). When calculating the Shannon Species Diversity Index, we found that the scarring alopecia had significantly higher diversity and species evenness compared to the non-scarring subtypes. At the species level, the scarring alopecias had significantly less C.acnes (which is classified within the Firmicutes phyla), compared to the non-scarring subtypes (p=0.00046).

Figure 1 - Bar chart to show the mean distribution of three key scalp phyla per alopecia subcategory.

We are still currently interpreting these results, and no publications have arisen as of yet. We are particularly interested in the significant differences between the scarring and non-scarring alopecia. It is logical to hypothesise that a reduction in sebaceous gland secretions, due to the fibrosis, perhaps impacts the microbiome. In the gut dysbiosis community, ratios between bacteria are often used to categorise gut health. We in turn envisage that a similar metric could be applied here – a clinically diagnostic threshold in the levels of Firmicutes to Actinobacteria that could distinguish at least scarring from non-scarring alopecia. To further analyse the data, we have also started a collaboration with Andrea Constantinou, a dermatologist with a specialist interest in microbiome and alopecia."