Persistent latent infection with Neoehrlichia mikurensis can lead to malignant transformation of B cells and autoimmunity

BackgroundThe tick-borne bacterium Neoehrlichia (N.) mikurensis causes fever and vascular events of the veins in patients with compromised B cell immunity. Immunocompetent individuals are either healthy carriers of the infection or develop severe arterial vascular events. We have reported that N. mikurensis infection may contribute to the development of malignant B cell lymphomas.

HypothesesN. mikurensis causes latent infections of the vascular endothelium that can become symptomatic when B cell immunity is compromisedChronic stimulation of B cells by N. mikurensis can trigger autoimmunity and malignant transformation of B cellsAims and work planTo prove that N. mikurensis causes latent infections that reactivate when B cell defenses are suppressed.

Patients treated with anti-B cell therapy are monitored for reactivation of the infection and pre-existing specific T-cell reactivity.To establish that N. mikurensis infection contributes to the development of malignant B cell lymphomas.

The phenotypes, antigen-dependency and B cell receptor repertoire of lymphomas of infected patients is compared with non-infected lymphoma patients.To determine if N. mikurensis infection can trigger autoimmunity.

B- and T-cell reactivity to bacteria and endothelium is evaluated in infected patients, including those with polymyalgia rheumatica.To evaluate if blood transfusions can transmit N. mikurensis infection. The infectivity of blood products from infected donors is tested in vitro.