Clonal isolation of Borrelia miyamotoi identifies multiple infection phenotypes and potential novel virulence determinants.

Authors

Dawn Cleveland, Yvonne Tourand, Timothy Casselli, Trevor Long, Hoa Nguyen, Amy Aldinger, Heidi Pecoraro, Catherine A Brissette

Published in

Microbiology spectrum. Pages e0152626. Oct 06, 2026. Epub Oct 06, 2026.

Abstract

Borrelia miyamotoi is an emerging tick-borne pathogen in the Northern Hemisphere that causes a relapsing fever-like illness known as Borrelia miyamotoi disease. Despite increased recognition of B. miyamotoi as a human pathogen, the mechanisms underlying infection and pathology remain poorly understood. During routine cultivation of B. miyamotoi LB-2001, our lab observed that bacterial cultures extensively passaged in vitro (over 70 passages) lost the ability to establish infection in severe combined immunodeficiency (SCID) mice. Clonal populations were isolated from both high- and low-passage cultures, and three distinct phenotypes were emerged-infections, attenuated, and non-infectious-each showing an inverse correlation between culture growth and infectivity in SCID mice. Infection outcomes in mice revealed differences in spirochetemia, hepatosplenomegaly, and anemia among the clones. Genomic DNA sequencing identified potential virulence determinants associated with these infectious phenotypes. These findings lay the groundwork for uncovering molecular mechanisms of B. miyamotoi pathogenesis and identifying targets to mitigate the impact of this emerging pathogen.IMPORTANCEAs global expansion of tick habitats increases, tick-borne diseases are becoming more prevalent and widespread. The emerging tick-borne pathogen Borrelia miyamotoi warrants increased scrutiny. This work demonstrates loss of infectivity in immunocompromised mice by B. miyamotoi subjected to continual in vitro cultivation, as well as the isolation of clonal populations that demonstrate differences in infectivity with three distinct phenotypes: infectious, attenuated, and non-infectious. Characterizing how clonal isolates have differences in infectivity can lead to the identification of novel factors required for virulence.

PMID:
42836682
Bibliographic data and abstract were imported from PubMed on 06 Oct 2026.

Read full publication at:
Please sign in to see all details.

Stats

1-terrible, 9-excellent. How would you rate this publication? Sign in in to submit your rating.

Post a comment

You need to be signed in to post comments. You can sign in here.

Comments

There are no comments yet.