Biology subjects

Gerdes, L. A.

Publications and source records attributed to Gerdes, L. A..

3 recordsLinked to original sources

bioRxiv2026

Pathogenicity of autoreactive TH17 cells is modulated by the TRPM7 kinase

The melastatin-like transient receptor potential channel, TRPM7, is crucial for signaling in leukocytes. It harbors a channel domain, permeable to divalent cations as well as a serine/threonine -kinase, phosphorylating inter alia SMAD2. TRPM7 kinase activity is essential for the differentiation of non-pathogenic T helper 17 (TH17) cells as well as for T cell colonization and alloreactivity in the gut. As pathogenic TH17 (pTH17) cells drive autoimmune diseases, we studied TRPM7 kinase involvement in pTH17 polarization and function as well as in the development of multiple sclerosis (MS), using human T cells and established murine experimental autoimmune encephalomyelitis (EAE) models. Our results reveal an elevated TRPM7 activity in T effector cells derived from the cerebrospinal fluid (CSF) of MS patients, in line with higher functional TRPM7 expression on human TH17 cells. Utilizing a mouse line with disrupted kinase activity (Trpm7R/R), we uncovered both impaired differentiation of pathogenic TH17 cells as well as a significantly milder course of TH17-mediated transfer EAE in Trpm7R/R mice compared to Trpm7+/+ controls. In the CNS of Trpm7R/R mice, the number of FOXP3+ T cells (Tregs) was increased, while fewer TH17 cells infiltrated the CNS due to a migration defect of transferred pTH17 cells in the Trpm7R/R hosts and a failure to reactivate in the intestine, due to reduced MHCII signaling. Thus, inactivation of TRPM7 kinase may represent a promising therapeutic strategy targeting both differentiation and reactivation of pTH17 cells while preserving Tregs function and thereby dampening CNS inflammation in MS.

immunology↗

bioRxiv2022

Persistent virus-specific and clonally expanded antibody secreting cells respond to induced self antigen in the CNS

B cells contribute to the pathogenesis of both cellular- and humoral-mediated central nervous system (CNS) inflammatory diseases through a variety of mechanisms. In such conditions, B cells may enter the CNS parenchyma and contribute to local tissue destruction. It remains unexplored, however, how infection and autoimmunity drive transcriptional phenotypes, repertoire features, and antibody functionality. Here, we profiled B cells from the CNS of murine models of intracranial (i.c.) viral infections and autoimmunity. We identified a population of clonally expanded, antibody secreting cells (ASCs) that had undergone class-switch recombination and extensive somatic hypermutation following i.c. infection with attenuated lymphocytic choriomeningitis virus (rLCMV). Recombinant expression and characterisation of these antibodies revealed specificity to viral antigens (LCMV glycoprotein GP), correlating with ASC persistence in the brain weeks after resolved infection. Furthermore, these virus-specific ASCs upregulated proliferation and expansion programs in response to the conditional and transient induction of the LCMV GP as a neo-self antigen by astrocytes. This class-switched, clonally expanded, and mutated population persisted and was even more pronounced when peripheral B cells were depleted prior to autoantigen induction in the CNS. In contrast, the most expanded B cell clones in mice with persistent expression of LCMV GP in the CNS did not exhibit neo-self antigen specificity, potentially a consequence of local tolerance induction. Finally, a comparable population of clonally expanded, class-switched, proliferating ASCs was detected in the cerebrospinal fluid of multiple sclerosis patients. Taken together, our findings support the existence of B cells that populate the CNS and are capable of responding to locally encountered autoantigens. Graphical abstract O_FIG_DISPLAY_L [Figure 1] M_FIG_DISPLAY C_FIG_DISPLAY

immunology↗

bioRxiv2018

DNA methylation signatures of a large cohort monozygotic twins clinically discordant for multiple sclerosis

Multiple sclerosis (MS) is an inflammatory demyelinating disease of the central nervous system with a modest concordance rate in monozygotic twins that strongly argues for involvement of epigenetic factors. We observe in 45 MS discordant monozygotic twins highly similar peripheral blood mononuclear cell-based methylomes. However, a few MS-associated differentially methylated positions (DMP) were identified and validated, including a region in the TMEM232 promoter and ZBTB16 enhancer. In CD4+ T cells we observed an MS-associated differentially methylated region in FIRRE. In addition, many regions showed large methylation differences in individual pairs, but were not clearly associated with MS. Furthermore, epigenetic biomarkers for current interferon-beta treatment were identified, and extensive validation revealed the ZBTB16 DMP as a signature of prior glucocorticoid treatment. Altogether, our study represents an important reference for epigenomic MS studies. It identifies new candidate epigenetic markers, highlights treatment effects and genetic background as major confounders, and argues against some previously reported MS-associated epigenetic candidates.

genomics↗