Ampel BioSolutions (United States)

Abstract Description Adenosine receptor dysregulation has been linked with lupus disease exacerbation as it plays a crucial role in immune modulation. We hypothesized that either activation of A2AR or inhibition of the A2BR would decrease lupus disease severity. Lupus prone NZB/W female mice were intraperitoneally injected daily for 12 weeks with ADO-5024 (A2BR antagonist) or ADO-6001 (A2AR agonist) beginning at 20 weeks-of-age. As controls, mice received dexamethasone (DEX) or PBS. As they aged, urine was assessed for proteinuria and inflammatory cytokines were measured in the sera. At 32 weeks-of-age, the mice were euthanized, and spleen and kidney tissue were assessed. Our findings showed that mice treated with the ADO-5024 had overall attenuated lupus disease not statistically different from DEX treatment, while those treated with the ADO-6001 and PBS were statistically different from the former across all parameters including proteinurea, renal pathology, and inflammatory cytokine expression. Mice treated with ADO-5024 showed decreased inflammatory profiles as observed by multiplex assay measuring cytokines like BAFF, TNF-a, and more. The ADO-5024 and DEX treated mice showed reduced IgG and C3 deposition and decreasing trends of glomerular and interstitial inflammation score compared to the PBS treated or ADO-6001 treated animals. Overall, our data suggests that inhibition of the A2BR may have therapeutic potential in treating lupus disease and more specifically lupus nephritis. Funding Sources Supported by Virginia Catalyst Grant; and NIH 1U2CDK129500-01 Topic Categories Basic Autoimmunity (BA)

Emerging evidence indicates that memory B cells are dysfunctional in systemic lupus erythematosus (SLE). They are hyporesponsive to signalling through the B cell receptor (BCR) but retain responsiveness to Toll-like receptor (TLR) and type I interferon signalling, as well as to T cell-mediated activation via CD40-CD154. Chronic exposure to immune complexes of ribonucleoprotein (RNP)-specific autoantibodies and TLR-engaging or BCR-engaging cargo is likely to contribute to this partially anergic phenotype. TLR7 or TLR8 signalling and the resulting production of type I interferon, as well as the sustained activation by bystander T cells, fuel a positive feedforward loop in memory B cells that can evade negative selection and permit preferential expansion of anti-RNP autoantibodies. Clinical trials of autologous stem cell transplantation or of B cell-targeted monoclonal antibodies and chimeric antigen receptor (CAR) T cells have correlated replenishment of the memory B cell population with relapse of SLE. Moreover, the BCR hyporesponsiveness of memory B cells might explain the failure of non-depleting B cell-targeting approaches in SLE, including BTK inhibitors and anti-CD22 monoclonal antibodies. Thus, targeting of dysfunctional memory B cells might prove effective in SLE, while also avoiding the adverse events of broad-spectrum targeting of B celland plasma cell subsets that are not directly involved in disease pathogenesis.

Chimeric antigen receptors (CARs) are synthetic proteins designed to direct an immune response toward a specific target and have been used in immunotherapeutic applications through the adoptive transfer of T cells genetically engineered to express CARs. This technology received early attention in oncology with particular success in treatment of B cell malignancies leading to the launch of numerous successful clinical trials and the US Food and Drug Administration approval of several CAR-T-based therapies. Many CAR-T constructs have been employed, but have always been administered following a lymphodepletion regimen. The success of CAR-T cell treatment in targeting malignant B cells has led many to consider the potential for using these regimens to delete pathogenic B cells in autoimmune diseases. Preliminary results have suggested efficacy, but the sample size remains small, controlled trials have not been done, the role of immunodepletion has not been established, the most effective CAR-T constructs have not been identified and the most appropriate patient subsets for treatment have not been established.

BackgroundIberdomide is a high affinity cereblon ligand that promotes ubiquitylation and proteasomal degradation of Ikaros (IKZF1) and Aiolos (IKZF3) transcription factors and, thereby altering specific aspects of immune responsiveness. Iberdomide has been shown to be efficacious in a randomized controlled trial in patients with generalized SLE (NCT03161483) and to be specifically effective in patients with high baseline expression of the interferon gene signature (IGS)[1,2].ObjectivesThe goal of this study was to identify subsets of SLE patients responsive to iberdomide more effectively by analyzing baseline gene expression profiles.MethodsBaseline whole blood samples from 276 female SLE patients from the phase 2b iberdomide trial were utilized for this analysis. These patients had a >/= 6 month history of SLE and disease activity determined by SLEDAI-2K >/=6. Patients were randomized to placebo, or one of three doses of iberdomide (0.15, 0.3 or 0.45 mg per day). Clinical response was determined by the SLE Responder Index 4 (SRI-4) at 24 weeks. RNAseq was performed and analyzed by Gene Set Variation Analysis (GSVA) using 32 informative gene modules and K-means clustering.ResultsWhole blood K-means clustering of the GSVA scores yielded 5 clusters or endotypes (Figure 1). Cluster 0 had the fewest molecular abnormalities, whereas Cluster 1 had the most disturbances in immune function, including enrichments in the interferon gene signature (IGS), immunoproteasome, IL-1/ inflammasome pathway, and neutrophil/granulocyte genes. Clusters 2-3 had intermediate degrees of abnormal enrichment in specific gene modules. Cluster 4 had high IGS, immunoproteasome, plasma cells/Ig chains, and IL-23 complex genes. No differences were noted between the subsets with regard to steroid or hydroxychloroquine use and differed only slightly in disease activity as measured by SLEDAI-2K. In general, cluster 1 had the most severe clinical laboratory measures with the highest anti-dsDNA antibodies and lowest C3 and C4. Clinical responses to iberdomide were confined to clusters 1 and 4. Effect sizes of responses in these groups approximated 30%. Other clusters had higher placebo responses and no additional response to iberdomide.ConclusionK-means clustering of GSVA scores from baseline samples of the iberdomide trial successfully clustered patients into endotypes that exhibited differences in response to iberdomide treatment, with the greatest responses observed in patients with the highest IGS, immunoproteasome, plasma cell, inflammasome, and IL-23 pathways. Gene expression based subsetting (endotyping) may be useful to enrich trials for responsive patients.

Regulation of intron retention (IR), a form of alternative splicing, is a newly recognized checkpoint in gene expression. Since there are numerous abnormalities in gene expression in the prototypic autoimmune disease systemic lupus erythematosus (SLE), we sought to determine whether IR was intact in patients with this disease. We, therefore, studied global gene expression and IR patterns of lymphocytes in SLE patients. We analyzed RNA-seq data from peripheral blood T cell samples from 14 patients suffering from systemic lupus erythematosus (SLE) and 4 healthy controls and a second, independent data set of RNA-seq data from B cells from16 SLE patients and 4 healthy controls. We identified intron retention levels from 26,372 well annotated genes as well as differential gene expression and tested for differences between cases and controls using unbiased hierarchical clustering and principal component analysis. We followed with gene-disease enrichment analysis and gene-ontology enrichment analysis. Finally, we then tested for significant differences in intron retention between cases and controls both globally and with respect to specific genes. Overall decreased IR was found in T cells from one cohort and B cells from another cohort of patients with SLE and was associated with increased expression of numerous genes, including those encoding spliceosome components. Different introns within the same gene displayed both up- and down-regulated retention profiles indicating a complex regulatory mechanism. These results indicate that decreased IR in immune cells is characteristic of patients with active SLE and may contribute to the abnormal expression of specific genes in this autoimmune disease.

IntroductionPathologic inflammation is a major driver of kidney damage in lupus nephritis (LN), but the immune mechanisms of disease progression and risk factors for end organ damage are poorly understood.MethodsTo characterize molecular profiles through the development of LN, we carried out gene expression analysis of microdissected kidneys from lupus-prone NZM2328 mice. We examined male mice and the congenic NZM2328.R27 strain as a means to define mechanisms associated with resistance to chronic nephritis. Gene expression profiles in lupus mice were compared with those in human LN.ResultsNZM2328 mice exhibited progress from acute to transitional and then to chronic glomerulonephritis (GN). Each stage manifested a unique molecular profile. Neither male mice nor R27 mice progressed past the acute GN stage, with the former exhibiting minimal immune infiltration and the latter enrichment of immunoregulatory gene signatures in conjunction with robust kidney tubule cell profiles indicative of resistance to cellular damage. The gene expression profiles of human LN were similar to those noted in the NZM2328 mouse suggesting comparable stages of LN progression.ConclusionsOverall, this work provides a comprehensive examination of the immune processes involved in progression of murine LN and thus contributes to our understanding of the risk factors for end-stage renal disease. In addition, this work presents a foundation for improved classification of LN and illustrates the applicability of murine models to identify the stages of human disease.

EDITORIAL article Front. Surg., 30 January 2023Sec. Orthopedic Surgery Volume 10 - 2023 | https://doi.org/10.3389/fsurg.2023.1132752