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Increased arthritis severity in mice coinfected with Borrelia burgdorferi and Babesia microti
Manuel H Moro1, Ofelia L Zegarra-Moro, Johannes Bjornsson
1Department of Immunology, Mayo Foundation, Rochester, Minnesota, MN, USA. moro.manuel@mayo.edu
Abstract:
Increased severity of disease and persistence of symptoms have been recently reported in some patients with simultaneous infection of Borrelia burgdorferi and Babesia microti in the northeastern and northern midwest United States. This study used a murine model to examine whether defined disease conditions such as arthritis and carditis differed in severity in mice infected solely with B. burgdorferi and in mice coinfected with B. microti and B. burgdorferi. C3H.HeJ and BALB/c mice cohorts were coinfected or singly infected and then monitored experimentally for 15 and 30 days after inoculation. Carditis and arthritis was determined by blinded histopathologic evaluation of myocardium and tibiotarsal joints. Cytokine measurements were made on lymph node and spleen supernatants for interferon-gamma, interleukin (IL)-4, IL-10, and IL-13. No differences were observed for C3H.HeJ mice cohorts; however, coinfected BALB/c mice had a significant increase in arthritis severity at day 30. This clinical observation was correlated with a significant reduction in expression of the cytokines IL-10 and IL-13.
Insights
Coinfection with Babesia microti and Borrelia burgdorferi can worsen arthritis in mice. This Lyme disease coinfection model showed increased severity linked to reduced IL-10 and IL-13 cytokine expression.
Area of Science:
- Immunology
- Infectious Diseases
- Pathology
Background:
- Simultaneous Borrelia burgdorferi (Lyme disease agent) and Babesia microti infections are reported with increased disease severity.
- Understanding coinfection dynamics is crucial for diagnosing and treating tick-borne illnesses.
Purpose of the Study:
- To investigate if coinfection with Babesia microti exacerbates Borrelia burgdorferi-induced arthritis and carditis in a murine model.
- To correlate observed disease severity with specific cytokine expression profiles.
Main Methods:
- Murine models (C3H.HeJ and BALB/c mice) were infected with either B. burgdorferi alone or coinfected with B. microti and B. burgdorferi.
- Mice were monitored for 15 and 30 days post-inoculation.
- Arthritis and carditis severity were assessed via histopathology; cytokine levels (IFN-γ, IL-4, IL-10, IL-13) were measured in supernatants.
Main Results:
- No significant differences in disease severity were observed in C3H.HeJ mice.
- BALB/c mice coinfected with B. microti and B. burgdorferi exhibited significantly increased arthritis severity at day 30.
- This heightened arthritis correlated with significantly reduced expression of interleukin-10 (IL-10) and interleukin-13 (IL-13).
Conclusions:
- Coinfection with Babesia microti can worsen Borrelia burgdorferi-induced arthritis in susceptible mouse strains (BALB/c).
- The exacerbation of arthritis in coinfected mice is associated with a suppressed immune response, indicated by reduced IL-10 and IL-13 levels.
- These findings highlight the complex interplay between tick-borne pathogens and host immune responses.
