Novel autoantibodies help diagnose anti-SSA antibody negative Sjögren disease and predict abnormal labial salivary gland pathology.

OBJECTIVES: Sjögren disease (SjD) diagnosis often requires either positive anti-SSA antibodies or a labial salivary gland biopsy with a positive focus score (FS). One-third of patients with SjD lack anti-SSA antibodies (SSA-), requiring a positive FS for diagnosis. Our objective was to identify novel autoantibodies to diagnose 'seronegative' SjD. METHODS: IgG binding to a high-density whole human peptidome array was quantified using sera from SSA- SjD cases and matched non-autoimmune controls. We identified the highest bound peptides using empirical Bayesian statistical filters, which we confirmed in an independent cohort comprising SSA- SjD (n=76), sicca-controls without autoimmunity (n=75) and autoimmune-feature controls (SjD features but not meeting SjD criteria; n=41). In this external validation, we used non-parametric methods for binding abundance and controlled false discovery rate in group comparisons. For predictive modelling, we used logistic regression, model selection methods and cross-validation to identify clinical and peptide variables that predict SSA- SjD and FS positivity. RESULTS: IgG against a peptide from D-aminoacyl-tRNA deacylase (DTD2) bound more in SSA- SjD than sicca-controls (p=0.004) and combined controls (sicca-controls and autoimmune-feature controls combined; p=0.003). IgG against peptides from retroelement silencing factor-1 and DTD2 were bound more in FS-positive than FS-negative participants (p=0.010; p=0.012). A predictive model incorporating clinical variables showed good discrimination between SjD versus control (area under the curve (AUC) 74%) and between FS-positive versus FS-negative (AUC 72%). CONCLUSION: We present novel autoantibodies in SSA- SjD that have good predictive value for SSA- SjD and FS positivity.

The Importance of Outcomes Ascertainment for Accurate Assessment of the Mammography Screening Cancer Detection Rate: A Simulation Study.

PURPOSE: Cancer detection rate (CDR), an important metric in the mammography screening audit, is designed to ensure adequate sensitivity. Most practices use biopsy results as the reference standard; however, commonly ascertainment of biopsy results is incomplete. We used simulation to determine the relationship between the cancer ascertainment rate of biopsy (AR-biopsy), CDR estimation, and associated error rates in classifying whether practices and radiologists meet the established ACR benchmark of 2.5 per 1,000. MATERIALS AND METHODS: We simulated screening mammography volume, number of cancers detected, and CDR, using negative binomial and beta-binomial distributions, respectively. Simulations were performed at both the practice and radiologist level. Average CDR was based on linearly rescaling a published CDR by the AR-biopsy. CDR distributions were simulated for AR-biopsy between 5% and 100% in steps of five percentage points and were summarized with boxplots and smoothed histograms over the range of AR-biopsy, to quantify the proportion of practices and radiologists meeting the ACR benchmark at each level of AR-biopsy. RESULTS: Decreasing AR-biopsy led to an increasing probability of categorizing CDR performance as being below the ACR benchmark. Our simulation predicts that at the practice level, an AR-biopsy of 65% categorizes 17.6% below the benchmark (compared to 1.6% at an AR-biopsy of 100%), and at the radiologist level, an AR-biopsy of 65% categorizes 34.7% as being below the benchmark (compared to 11.6% at an AR-biopsy of 100%). CONCLUSIONS: Our simulation demonstrates that decreasing the AR-biopsy (in currently clinically relevant ranges) has the potential to artifactually lower the assessed CDR on both the practice and radiologist levels and may, in turn, increase the chance of erroneous categorization of underperformance per the ACR benchmark.

ATM inhibition augments type I interferon response and antitumor T-cell immunity when combined with radiation therapy in murine tumor models.

BACKGROUND: Radiation therapy (RT) elicits DNA double-strand breaks, resulting in tumor cytotoxicity and a type I interferon (IFN) response via stimulator of interferon genes (STING) activation. We investigated whether combining RT with an ataxia-telangiectasia mutated inhibitor promoted these effects and amplified tumor immunity. METHODS: Mice-bearing syngeneic flank tumors (MOC2 head and neck squamous cell carcinoma or B78 melanoma) were treated with tumor-directed RT and oral administration of AZD0156. Specific immune cell depletion, type 1 interferon receptor 1 knock-out mice (IFNAR1-KO), and STING-deficient tumor cells were used to investigate tumor-immune crosstalk following RT and AZD0156 treatment. RESULTS: Combining RT and AZD0156 reduced tumor growth compared with RT or AZD0156 alone in mice bearing MOC2 or B78 tumors. Low-dose AZD0156 (1-100 nM) alone did not affect tumor cell proliferation but suppressed tumor cell clonogenicity in combination with RT. Low-dose AZD0156 with RT synergistically increased IFN-ß, major histocompatibility complex (MHC)-I, and programmed death-ligand 1 (PD-L1) expression in tumor cells. In contrast to wild-type mice, IFNAR1-KO mice showed reduced CD8+T cell tumor infiltration and poor survival following RT+AZD0156 treatment. CD8+T cell depletion reduced antitumor response during RT+AZD0156 treatment. STING-deficient MOC2 (MOC2-STING+/-) or B78 (B78-STING-/-) tumors eliminated the effects of RT+AZD0156 on the expression of IFN-ß, MHC-I, and PD-L1, and reduced CD8+T cell infiltration and migration. Additional anti-PD-L1 therapy promoted antitumor response by elevation of tumor-MHC-I and lymphocyte activation. CONCLUSIONS: Combined radiation and AZD0156 increase STING-dependent antitumor response. Tumor-derived cell-autonomous IFN-ß amplification drives both MHC-I and PD-L1 induction at the tumor cell surface, which is required by anti-PD-L1 therapy to promote antitumor immune response following RT and AZD0156 combination therapy.

Novel autoantibodies help diagnose anti-SSA antibody negative Sjögren's disease and predict abnormal labial salivary gland pathology.

Objectives: Sj□gren's disease (SjD) diagnosis requires either positive anti-SSA antibodies or a labial salivary gland biopsy with a positive focus score (FS). One-third of SjD patients lack anti-SSA antibodies (SSA-), requiring a positive FS for diagnosis. Our objective was to identify novel autoantibodies to diagnose 'seronegative' SjD. Methods: IgG binding to a high density whole human peptidome array was quantified using sera from SSA- SjD cases and matched non-autoimmune controls. We identified the highest bound peptides using empirical Bayesian statistical filters, which we confirmed in an independent cohort comprising SSA- SjD (n=76), sicca controls without autoimmunity (n=75), and autoimmune controls (SjD features but not meeting SjD criteria; n=41). In this external validation, we used non-parametric methods for peptide abundance and controlled false discovery rate in group comparisons. For predictive modeling, we used logistic regression, model selection methods, and cross-validation to identify clinical and peptide variables that predict SSA- SjD and FS positivity. Results: IgG against a peptide from D-aminoacyl-tRNA deacylase (DTD2) was bound more in SSA- SjD than sicca controls (p=.004) and more than combined controls (sicca and autoimmune controls combined; p=0.003). IgG against peptides from retroelement silencing factor-1 (RESF1) and DTD2, were bound more in FS-positive than FS-negative participants (p=.010; p=0.012). A predictive model incorporating clinical variables showed good discrimination between SjD versus control (AUC 74%) and between FS-positive versus FS-negative (AUC 72%). Conclusion: We present novel autoantibodies in SSA- SjD that have good predictive value for SSA- SjD and FS-positivity. KEY MESSAGES: What is already known on this topic - Seronegative (anti-SSA antibody negative [SSA-]) Sjögren's disease (SjD) requires a labial salivary gland biopsy for diagnosis, which is challenging to obtain and interpret. What this study adds - We identified novel autoantibodies in SSA- SjD that, when combined with readily available clinical variables, provide good predictive ability to discriminate 1) SSA- SjD from control participants and 2) abnormal salivary gland biopsies from normal salivary gland biopsies. How this study might affect research, practice or policy - This study provides novel diagnostic antibodies addressing the critical need for improvement of SSA- SjD diagnostic tools.