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More details about our L-form Bacteria Project: Key research hypothesis
L-form, wall-less, organisms exist in the blood, cells, and tissues of humans potentially evolving with their hosts. Although most of the data on L-forms associated with human disease are unpublished data from our collaborator Softcell Biological Research others have published on the presence of bacteria in the human circulation1. We speculate that a set of L-forms organisms likely works in harmony with the host, potentially providing key metabolites and impacting on other currently un-identified cellular processes. Transmission via the placenta may be possible2 with L-forms potentially also acquired over time from the environment via the gut3.
If present in human hosts, levels and types of L-forms will be controlled by a currently unidentified system. With many similarities to mitochondria, we propose that a mechanism regulating L-form bacteria could also impact on mitochondrial/energetic function. L-forms are likely to generate a very different immune response to walled bacteria which are dealt with by complement, phagocytosis, and adaptive immunity. Recent studies by Kawai et al (2018) indicated that once engulfed by macrophages bacteria can enter an L-form state evading the body's defense systems4.
We propose that the presence of deleterious L-form organisms is the driving force behind many chronic disease states associated with a range of symptoms depending upon the type of organisms present, their location, and secretory metabolites. L-forms have been recently identified in urinary tract infections with the ability to convert readily into the walled state5. We hypothesise that returning L-form populations to the normal L-form complement will result in the resolution of symptoms. Treatment with antibiotics and antifungal agents specifically targeted to the L-forms present in the patient could also provide a new therapeutic option for a range of chronic diseases including ME/CFS, fibromyalgia, endometriosis, migraine and joint and bone problems.
In this project, we will thoroughly characterise L-forms in the blood of patients using whole genome sequencing and culturing L-forms from individual patients and controls. Standard antibiotic and anti-fungal agents will be tested in in vitro and a database generated on the drug combinations which are effective for individual L form species. A new research study will be established to determine which blood cells contain L-forms and the impact on immune and blood cell function. L-forms cultured from ME/CFS patients will also be used to infect human cell lines with a thorough characterisation of the effect on cell function. Recent studies in ME/CFS suggest higher levels of mucosal-associated invariant T cells (MAIT cells) in patients which is consistent with a bacterial infection.
Oxford researchers and clinicians
ME/CFS patients diagnosed with the Canadian and/or International Consensus criteria and two non-ME/CFS cohorts with varying degrees of fatigue: minor stroke and lymphoma patients will be recruited from Oxford clinics. 100 patients in each group will be recruited over 2 years, together with 100 healthy controls. Disability will be further characterised by the MFI (Multidimensional fatigue inventory) and SF-36 questionnaires. For the ME/CFS cohort patients will be excluded if they were previously diagnosed or had a history of any alternative disease that would explain symptoms including autoimmune disorder, multiple sclerosis, psychosis, major depression, heart disease, or thyroid-related disorders, or if they are pregnant or breastfeeding. Recruitment for the two non-ME/CFS cohorts will be co-ordinated by Dr Collins (Lymphoma) and Dr Kennedy (Stroke) by LCRN research staff. ME/CFS patients will be recruited in collaboration with the local patient support group OMEGA and the Oxford Fatigue Service.
 Kowarsky, M., et al., Numerous uncharacterized and highly divergent microbes which colonize humans are revealed by circulating cell-free DNA. Proc Natl Acad Sci U S A, 2017. 114(36): p. 9623-9628.
 Dimova, T., et al., Mother-to-newborn transmission of mycobacterial L-forms and Vdelta2 T-cell response in placentobiome of BCG-vaccinated pregnant women. Sci Rep, 2017. 7(1): p. 17366.
 Illiano, P., R. Brambilla, and C. Parolini, The mutual interplay of gut microbiota, diet and human disease. FEBS J, 2020. 287(5): p. 833-855.
 Kawai, Y., K. Mickiewicz, and J. Errington, Lysozyme Counteracts beta-Lactam Antibiotics by Promoting the Emergence of L-Form Bacteria. Cell, 2018. 172(5): p. 1038-1049 e10.
 Mickiewicz, K.M., et al., Possible role of L-form switching in recurrent urinary tract infection. Nat Commun, 2019. 10(1): p. 4379.