Description
Increase in Lactobacillus and reduction in anaerobes in coronal sulcus during initial weeks following circumcision
Garson KL1, Lennard K1,2, Botha G1, Havyarimana E2, Blakney A3, Curry L2,4, Harryparsad R2, Olivier AJ2, Otwombe K5, Dietrich J5, Wilson D6, Gray C2, Jaspan H2,7,8, Mulder N1
1Computational Biology Division, University of Cape Town, South Africa; 2Immunology Division, University of Cape Town, South Africa; 3Department of Bioengineering, University of Washington, USA; 4Division of Forensic Medicine and Toxicology, University of Cape Town, South Africa; 5Perinatal HIV Research Unit, Faculty of Health Sciences, University of the Witwatersrand, South Africa; 6Department of Internal Medicine, Edendale Hospital, University of KwaZulu-Natal, South Africa; 7Seattle Children's Research Institute, USA; 8Departments of Pediatrics and Global Health, University of Washington, USA
Higher abundances of various anaerobic bacteria present on the uncircumcised penis have been linked to increased risk of HIV acquisition. Male circumcision lowers the abundance of these taxa and reduces this risk. Many of these taxa are also linked to increased risk of HIV acquisition in the female genital tract, while Lactobacillus species are known to have a protective role.
To investigate how these key taxa adapt in the early stages after circumcision, coronal sulcus swabs were collected from 14-24 year-old South African males prior to, and at 2, 12 and 24 weeks after circumcision.
The relative abundance of various anaerobic genera were significantly reduced by 12 weeks post-circumcision. In some cases, such as Peptoniphilus, Anaerococcus and Prevotella, the decline was moderate and consistent over time, while changes in relative abundance of Porphyromonas and Peptostreptococcus were more erratic. Mobiluncus relative abundance showed a sudden decrease at 2 weeks, remaining relatively constant thereafter. Conversely, Lactobacillus had significantly increased in relative abundance at 12 weeks. The abundance of Peptoniphilus and Lactobacillus were among the most characteristic features of pre- and post-circumcision composition.
Numerous taxa of interest present in the coronal sulcus show marked changes in the weeks following circumcision, which varied by genus. Further insight could enhance methods to reduce HIV susceptibility in the genital tract.
Funding was provided by the South African National Research Foundation and the European & Developing Countries Clinical Trials Partnership.