biostudies-arrayexpressMorgan WilliamsHomo sapienshttps://www.ebi.ac.uk/biostudies/studies/E-MTAB-16016A TLR1 variant (1805GG) associated with severe Lyme disease may drive excessive inflammation. To investigate this, we stimulated (16hr) and restimulated (6hr) PBMCs from donors with or without TLR1-1805GG using Borrelia burgdorferi. Variant carriers showed stronger transcriptional and cytokine responses and failed to develop innate immune tolerance upon restimulation, indicating dysregulated inflammation that may underlie persistent disease.biostudies-arrayexpressLibrary Construction - Libraries were prepared using NEBNext Ultra-II Directional RNA Library Prep Kit (Illumina).Sequencing - Sequencing was performed (150bp paired-end) using Illumina HiSeq, generating ~25 million reads per sample.Nucleic Acid Extraction - Total RNA was extracted using Rneasy Plus Micro Kit (Qiagen).Growth Protocol - PBMCs were maintained in RPMI 1640 supplemented with 10% heat-inactivated fetal bovine serum (HI-FBS) in humidified atmosphere with 5% CO2 at 37C.Sample Collection - Cells were harvested following stimulation (16hr) and restimulation (6hr) for total RNA extraction.Sample Treatment - Control cells were given growth medium at stimulation and restimulation. Stimulated and Restimulated cells were treated with live B. burgdorferi.OrganizationMINSEQE ScoreAssays and DataProcessed DataMAGE-TAB FilesData Transformation - Transcripts per million (TPM) normalization of RNA-seq data was performed.Sequence Alignment - Sequences were aligned to the human genome (hg38) using STAR RNA-seq aligner.MetabolomicsUnknownTranscriptomicsGenomicsProteomicsIllumina HiSeq 2500<h4>Introduction</h4>Clinical presentation of Lyme disease is largely due to host immune response to infection. Previously, we identified a variant (1805GG) in the TLR1 gene, a key immune sensor for <i>Borrelia burgdorferi</i>, which was associated with excessive inflammation and severe disease. Herein we examined the mechanism by which this variant leads to dysregulated immunity.<h4>Methods</h4>We found that patients with post-infectious Lyme arthritis, a condition characterized by marked persistent synovitis in joints, have a higher frequency of TLR1-1805GG compared to those whose arthritis resolves with antibiotics. To explore the possibility that this genotype-phenotype association was due to excessive inflammation, we then tested the functional impact of TLR1-1805GG on inflammatory responses and immune tolerance in PBMCs with or without this SNP and in THP-1 cell lines lacking TLR1.<h4>Results</h4>In response to <i>B. burgdorferi</i> stimulation, PBMCs with TLR1-1805GG had greater transcriptional upregulation of ~1200 immune-related genes and significantly higher cytokine levels in supernatants compared to cells without this variant. Moreover, repeat <i>B. burgdorferi</i> stimulation, which mimics tolerogenic conditions during the infection, failed to induce innate immune tolerance in PBMCs with TLR1-1805GG, or in THP-1 cells lacking TLR1, resulting in seemingly unabated immune activation consistent with marked inflammation in Lyme arthritis joints.<h4>Conclusions</h4>These results suggest that excessive inflammation in patients with TLR1-1805GG variant appears to be due to immune dysregulation and inability to induce immune tolerance. The findings help explain how early events during the infection may contribute to sustained immune activation after antibiotics and point to the role of TLR1 signaling in immune regulation.RNA-seq of total RNAHomo sapiensToll-like receptor 1 polymorphism is associated with impaired immune tolerance, dysregulated inflammatory responses to Borrelia burgdorferi, and heightened risk of post-infectious Lyme arthritisWilliams MA, Hernandez SA, Arvikar SL, Sulka KB, Strle F, Wells CC, Petnicki-Ocwieja T, Steere AC, Strle KMorgan WilliamsfalseRNA-seq analysis of PBMCs with TLR1-1805TT and TLR1-1805GG genotypes stimulated and restimulated (innate immune tolerance induction) with B. burgdorferi.A TLR1 variant (1805GG) associated with severe Lyme disease may drive excessive inflammation. To investigate this, we stimulated (16hr) and restimulated (6hr) PBMCs from donors with or without TLR1-1805GG using Borrelia burgdorferi. Variant carriers showed stronger transcriptional and cytokine responses and failed to develop innate immune tolerance upon restimulation, indicating dysregulated inflammation that may underlie persistent disease.2025-11-13T00:00:00Z2026-05-27T15:32:28.046Z2025-11-13T14:44:58.436ZE-MTAB-16016ERP183984EFO_0002944EFO_0004170EFO_0009653EFO_0003789EFO_0004917EFO_0005518EFO_0003816EFO_0004184EFO_000396910.3389/fimmu.2025.1711765