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Objective: Anti–citrullinated protein antibodies (ACPAs) have proven highly useful as biomarkers for rheumatoid arthritis (RA). However, composition and functionality of the associated autoreactive B cell repertoire have not been directly assessed. We aimed to selectively investigate citrullinated autoantigen–specific B cell receptors (BCRs) involved in RA and initiate studies on their pathogenicity. Methods: Blood samples were obtained from patients in a University of Minnesota cohort with ACPA‐positive RA (n = 89). Tetramer sets bearing citrullinated filaggrin peptide cfc1 or citrullinated α‐enolase peptide were constructed to specifically capture autoreactive B cells from the unaltered, polyclonal repertoire in RA patients. Citrullinated peptide tetramer–bound B cells were subjected to flow cytometric cell sorting and single‐cell IGH,IGK, and IGL gene sequencing for B cell lineage determinations. BCR gene sequences were also expressed as recombinant monoclonal antibodies (mAb) for direct evaluation of citrullinated autoantigen binding and effector functionality. Results: Using citrullinated peptide tetramer enrichment to investigate single autoreactive blood B cells, we identified biased V‐region gene usage and conserved junction arrangements in BCRs from RA patients. Parsimonious clustering of related immunoglobulin gene nucleotide sequences revealed clonal expansions of rare individual B cell clades, in parallel with divergent sequence mutations. Correspondingly, recombinant mAb generated from such BCR lineages demonstrated citrulline‐dependent cross‐reactivity extending beyond the citrullinated peptides used for B cell capture. A pair of citrullinated autoantigen–specific mAb with cross‐reactive binding profiles also promoted arthritis in mice. Conclusion: Our findings suggest that broad ACPA specificities in RA arise from a restricted repertoire of evolving citrulline‐multispecific B cell clades with pathogenic potential. [ABSTRACT FROM AUTHOR]

Background: Heart failure with preserved ejection fraction (HFpEF) is a clinical syndrome characterized by diastolic dysfunction. Despite the increasing incidence of HFpEF, there is no available therapy that reduces the mortality rate of HFpEF. Zhigancao Tang has been used traditionally for the treatment of cardiovascular diseases in China. The use of traditional Chinese medicine (TCM) is associated with improvements in clinical syndromes and quality of life of patients. A randomized clinical trial should be conducted to provide clear evidence regarding the efficacy and safety of Zhigancao Tang granules for the treatment of HFpEF., Methods: A randomized, double-blinded, placebo-controlled clinical trial was proposed. A total of 122 patients with HFpEF will be randomly assigned to receive Zhigancao Tang granules or placebo for 12 weeks. The primary outcome measure is cardiac function. The secondary outcomes include measurement of the integral TCM syndrome score, echocardiography, 6-min walk test, N-terminal-pro hormone B-type natriuretic peptide level, atrial natriuretic peptide level, Minnesota Living with Heart Failure scale, and Lee's scale. The outcome measures will be evaluated at baseline, 4 weeks, and 12 weeks. Adverse events will be evaluated from baseline till the 12-week follow-up period., Discussion: The results of this trial will demonstrate whether Zhigancao Tang granules are effective and safe for treating HFpEF., Trial Registration: ClinicalTrials.gov NCT04317339 . Registered on 23 March 2020.