Autoantibody Signatures Research Articles

Isotype-Specific Autoantibody Signatures in Cancer and Sepsis Samples through Multiplex Profiling

Abstract Many diseases can be characterized by specific autoantibodies. The Luminex™ multi-analyte profiling platform enables simultaneous detection a panel of autoantibodies in a single assay with minimal sample volume. MILLIPLEX™ multiplex assays include the 15-plex Human Cancer Autoantibody Panel, 23-plex Human Cytokine Autoantibody Panel, and 20-plex Human Autoimmune Autoantibody Panel, allowing qualitative profiling of autoantibodies in serum and plasma samples. In this study, we focused on detecting cancer-associated autoantibodies and anti-cytokine autoantibodies in breast cancer, colorectal cancer, sepsis, and healthy control samples (n ≥ 20 in each group). We used the Luminex™ 200™ system and the xMAP™ INTELLIFLEX DRSE instrument for analysis. Preliminary data revealed anti-cytokine IgG autoantibodies against multiple cytokines (e.g., IL-2, IL-4, IFNγ) in cancer, sepsis, and healthy individuals. Additionally, certain cytokine autoantibodies (e.g., IL-1α, IL-12p40, IL-6) were detected in the tested disease samples but not in healthy controls. Isotype profiling demonstrated increased detection of cancer-associated autoantibodies by combining IgG and IgM signatures in cancer samples (e.g., p53, CCNB1/Cyclin B1, SOX2, CTAG1B/NY-ESO-1, Her2/ErbB2). We believe this robust MILLIPLEX™ autoantibody detection and comprehensive isotype profiling can guide further research on autoantibodies as translational biomarkers in a clinical setting.

An autoantibody signature predictive for multiple sclerosis.

Although B cells are implicated in multiple sclerosis (MS) pathophysiology, a predictive or diagnostic autoantibody remains elusive. In this study, the Department of Defense Serum Repository (DoDSR), a cohort of over 10 million individuals, was used to generate whole-proteome autoantibody profiles of hundreds of patients with MS (PwMS) years before and subsequently after MS onset. This analysis defines a unique cluster in approximately 10% of PwMS who share an autoantibody signature against a common motif that has similarity with many human pathogens. These patients exhibit antibody reactivity years before developing MS symptoms and have higher levels of serum neurofilament light (sNfL) compared to other PwMS. Furthermore, this profile is preserved over time, providing molecular evidence for an immunologically active preclinical period years before clinical onset. This autoantibody reactivity was validated in samples from a separate incident MS cohort in both cerebrospinal fluid and serum, where it is highly specific for patients eventually diagnosed with MS. This signature is a starting point for further immunological characterization of this MS patient subset and may be clinically useful as an antigen-specific biomarker for high-risk patients with clinically or radiologically isolated neuroinflammatory syndromes.

(50) - A Serum Autoantibody (AAB) Signature is Associated with Future CLAD

(50) - A Serum Autoantibody (AAB) Signature is Associated with Future CLAD

Profiling of autoantibodies in the sera of glioblastoma patients.

Aim: This study aimed to determine the expression pattern of autoantibody proteins from the serum of grade IV glioblastoma patients.Materials & methods: We performed high throughput antibody profiling via the Sengenics i-Ome® Protein Array to determine the differentially expressed autoantibodies.Results: The results portrayed that anti-COL4A3BP and anti-HSP90AA1 were among the upregulated autoantibodies in glioblastoma sera.Conclusion: The selected autoantibodies offer promising targets for future glioblastoma pathogenesis. However, further validation is required to elucidate the autoantibody signature in glioblastoma patients.

ADAMTS-13 conformation influences autoimmune recognition in immune thrombotic thrombocytopenic purpura

BackgroundPatients with immune-mediated thrombotic thrombocytopenic purpura (iTTP) have anti–ADAMTS-13 immunoglobulin G (IgG) autoantibodies that enhance ADAMTS-13 clearance and/or inhibit its function. ADAMTS-13 normally circulates in a closed conformation, which is manifested by the interaction of the CUB domains with the central spacer domain. Disruption of the spacer–CUB interaction opens ADAMTS-13, which augments its proteolytic function but may also expose cryptic autoimmune epitopes that promote further autoantibody recognition. ObjectivesTo explore differences in autoantibody binding to ADAMTS-13 in its closed or open conformations in patients with iTTP and to correlate these differences with disease-related parameters. MethodsWe developed a novel assay to measure autoantibodies binding to closed and open ADAMTS-13. Autoantibody titer and IgG subclass binding to open or closed ADAMTS-13 were measured in 70 iTTP first presentation samples and correlated with clinical data, remission, and relapse. ResultsIn 70 patients with iTTP, the mean autoantibody titer against open ADAMTS-13 was, on average, approximately 2-fold greater than that against closed ADAMTS-13, suggesting that ADAMTS-13 opening increases epitope exposure and immune complex formation. Autoantibody titer against closed/open ADAMTS-13 and IgG subclass did not correlate with ADAMTS-13 antigen at presentation. Two patients with iTTP and persistent autoantibodies lost specificity for closed ADAMTS-13 in remission. Recognition of closed/open ADAMTS-13 and autoantibody IgG subclass between the first and second iTTP episodes were very similar. ConclusionADAMTS-13 autoantibody binding is highly influenced by ADAMTS-13 conformation. Although this does not appear to modify the pathogenicity of autoantibodies, the autoantibody signature at relapse suggests that relapse represents re-emergence of the original autoimmune response rather than de novo presentation.

Transient Anti-Interferon Auto Antibodies in the Airway Are Associated with Recovery in Mild COVID-19

Pre-existing blood anti-interferon autoantibodies have been associated with susceptibility to severe COVID-19. However, nothing is known about the autoantibody response in the airway mucosa of mild to severe COVID-19 patients. We profiled longitudinal samples collected from the airway and matching blood of more than 100 donors over >18 months, spanning from mild COVID-19 to hospitalized patients in the ICU. We found that transiently induced anti-type I interferon autoantibodies in the nasal mucosa are a common feature and are associated with recovery from mild and moderate COVID-19. To quantify the breadth of antibody response in blood and the airway site of infection, we developed flowBEAT, a novel flow cytometry-based assay capable of simultaneously measuring all 8 human antibody isotypes against 22 SARS-CoV-2 structural and non-structural antigens, including autoantigens. We identified the induction of nasal anti-type I interferon autoantibodies within the first two weeks of infection, waning with disease recovery. Notably, there was an inverse association between nasal and blood anti-interferon responses, while nasal anti-interferon was linked to recovery in cases of mild/moderate disease. In contrast, near-ubiquitous anti-interferon in the endotracheal aspirates of critical cases correlated with heightened airway hyper-inflammation. In both blood and mucosa, anti-interferon positively correlated with a broad anti-viral antibody response, including non-structural proteins. While nasal anti-interferon was universally transient, we identified a group of donors sustaining long-term blood anti-interferon autoantibodies who may be at risk for a more severe subsequent viral infection. Within our longitudinal cohort, we assessed 500 infected-recovered and vaccinated samples and showed that nasal anti-SARS-CoV-2 antibodies are sustained over 18 months by repeated vaccination and boosting. We identified isotype signatures associated with disease severity and an autoantibody signature predictive of vaccine non-response. Thus, our findings emphasize the importance of continued vaccination/boosting to sustain nasal immunity and help prevent ongoing community spread. More importantly, our studies reveal predictive blood markers of protective nasal immunity and highlight a protective role for nasal anti-interferon autoantibodies in the immunopathology of COVID-19.

A novel autoantibody signatures for enhanced clinical diagnosis of pancreatic ductal adenocarcinoma

BackgroundPancreatic ductal adenocarcinoma (PDAC) is a devastating disease that requires precise diagnosis for effective treatment. However, the diagnostic value of carbohydrate antigen 19 − 9 (CA19-9) is limited. Therefore, this study aims to identify novel tumor-associated autoantibodies (TAAbs) for PDAC diagnosis.MethodsA three-phase strategy comprising discovery, test, and validation was implemented. HuProt™ Human Proteome Microarray v3.1 was used to screen potential TAAbs in 49 samples. Subsequently, the levels of potential TAAbs were evaluated in 477 samples via enzyme-linked immunosorbent assay (ELISA) in PDAC, benign pancreatic diseases (BPD), and normal control (NC), followed by the construction of a diagnostic model.ResultsIn the discovery phase, protein microarrays identified 167 candidate TAAbs. Based on bioinformatics analysis, fifteen tumor-associated antigens (TAAs) were selected for further validation using ELISA. Ten TAAbs exhibited differentially expressed in PDAC patients in the test phase (P < 0.05), with an area under the curve (AUC) ranging from 0.61 to 0.76. An immunodiagnostic model including three TAAbs (anti-HEXB, anti-TXLNA, anti-SLAMF6) was then developed, demonstrating AUCs of 0.81 (58.0% sensitivity, 86.0% specificity) and 0.78 (55.71% sensitivity, 87.14% specificity) for distinguishing PDAC from NC. Additionally, the model yielded AUCs of 0.80 (58.0% sensitivity, 86.25% specificity) and 0.83 (55.71% sensitivity, 100% specificity) for distinguishing PDAC from BPD in the test and validation phases, respectively. Notably, the combination of the immunodiagnostic model with CA19-9 resulted in an increased positive rate of PDAC to 92.91%.ConclusionThe immunodiagnostic model may offer a novel serological detection method for PDAC diagnosis, providing valuable insights into the development of effective diagnostic biomarkers.

Patients with Systemic Juvenile Idiopathic Arthritis (SJIA) Show Differences in Autoantibody Signatures Based on Disease Activity.

Systemic juvenile idiopathic arthritis (SJIA) is a severe rheumatic disease in children. It is a subgroup of juvenile idiopathic arthritis (JIA; MIM #604302), which is the most common rheumatic disease in children. The diagnosis of SJIA often comes with a significant delay, and the classification between autoinflammatory and autoimmune disease is still discussed. In this study, we analyzed the immunological responses of patients with SJIA, using human proteome arrays presenting immobilized recombinantly expressed human proteins, to analyze the involvement of autoantibodies in SJIA. Results from group comparisons show several differentially reactive antigens involved in inflammatory processes. Intriguingly, many of the identified antigens had a high reactivity against proteins involved in the NF-κB pathway, and it is also notable that many of the detected DIRAGs are described as dysregulated in rheumatoid arthritis. Our data highlight novel proteins and pathways potentially dysregulated in SJIA and offer a unique approach to unraveling the underlying disease pathogenesis in this chronic arthropathy.

Cystic fibrosis autoantibody signatures associate with Staphylococcus aureus lung infection or cystic fibrosis-related diabetes.

While cystic fibrosis (CF) lung disease is characterized by persistent inflammation and infections and chronic inflammatory diseases are often accompanied by autoimmunity, autoimmune reactivity in CF has not been studied in depth. In this work we undertook an unbiased approach to explore the systemic autoantibody repertoire in CF using autoantibody microarrays. Our results show higher levels of several new autoantibodies in the blood of people with CF (PwCF) compared to control subjects. Some of these are IgA autoantibodies targeting neutrophil components or autoantigens linked to neutrophil-mediated tissue damage in CF. We also found that people with CF with higher systemic IgM autoantibody levels have lower prevalence of S. aureus infection. On the other hand, IgM autoantibody levels in S. aureus-infected PwCF correlate with lung disease severity. Diabetic PwCF have significantly higher levels of IgA autoantibodies in their circulation compared to nondiabetic PwCF and several of their IgM autoantibodies associate with worse lung disease. In contrast, in nondiabetic PwCF blood levels of IgA autoantibodies correlate with lung disease. We have also identified other autoantibodies in CF that associate with P. aeruginosa airway infection. In summary, we have identified several new autoantibodies and associations of autoantibody signatures with specific clinical features in CF.

Determinants of racial disparities in immune-related adverse events (irAE) with checkpoint inhibition (ICI) in melanoma.

9549 Background: We recently reported that a pretreatment autoantibody (AutoAb) signature predicts immune-related adverse events (irAE) with an AUC of ~0.80 in melanoma patients enrolled in two phase III clinical trials of adjuvant ICI (Johannet et al. CCR 2022). The vast majority of those patients were non-Hispanic whites (NHW). We hypothesized that underrepresented minority (URM) melanoma patients might have a different baseline autoAb profile compared to NHW patients, as their site-specific irAEs differ ( Xue Bai et al. Br J of Derm 2022) and autoimmune disease is generally more common in underrepresented minorities (Roberts MH, Erdei E. Autoimmune Review 2020). We also explored the possibility that differences in the immuno-biology of acral melanoma (AM) and cutaneous melanoma (CM) – most commonly detected in URM and NHW patients, respectively – might inform our understanding of the racial differences in irAEs. Methods: We compared pre-treatment sera autoAb from URM melanoma patients (n=35) to NHW patients (n= 185) enrolled in Checkmate-238 (NCT02388906), Checkmate-915 (NCT03068455) or the NYU melanoma program database using the CDI and Sengenics proteomic platforms, and analyzed their association(s) with the development of grade 3-4 irAEs. We carried out single cell RNA-seq in AM versus CM tumor tissues to test whether expression of genes whose proteins were associated with irAE were preferentially expressed in AM tissue. We also compared RNA-seq of an immunoregulatory gene panel in AM versus CM tumors. Results: We identified autoAbs that were only detected in sera from URM patients with grade 3-4 irAEs (e.g. ALDOA, BANK1, LDHB and RNF7) and autoAbs that were only detected in NHW patients with grade 3-4 irAEs (e.g. GMEB2, YWHAE and ANKRD45). A subset of these autoAb targets was preferentially expressed in AM or CM tissues, while other targets were undetected in these melanoma subtypes. Cytokine signaling pathways were enriched in sera from URM but not NHW patients, and expression of genes known to modulate irAEs and response to ICI were significantly more expressed in AM than CM tumors, e.g. FOXP3 ( P=0.01), IL2 ( P=0.00547), IL4 ( P=0.0221) and IL10 ( P=0.0126). Conclusions: Our data suggest that URM patients have an altered tumor immune microenvironment that defines their response to ICI and risk of developing irAE. An integrative analysis of both the tumor and systemic immune environments is needed to better understand molecular links between response to ICI and irAEs in URM and NHW melanoma patients. A multi-center study is planned to address these questions.

EPS4.08 Cystic fibrosis autoantibody signatures associate with Staphylococcus aureus lung infection and cystic fibrosis-related diabetes

Objectives: While cystic fibrosis (CF) lung disease is characterized by persistent inflammation and bacterial infections, and chronic inflammatory diseases are often accompanied by autoimmunity, autoimmune reactivity in CF has not been studied in depth. In this work our goal was to explore the autoantibody repertoire in CF.

Early and differential autoimmune diseases diagnosis by interrogating specific autoantibody signatures with multiplexed electrochemical bioplatforms

This work reports the first bioplatform to assist in the early and reliable diagnosis of autoimmune diseases by quadruple determination of autoantibodies (Abs) produced against extractable nuclear antigens (ENAs): La/SSB-Abs, Ro/SSA-Abs, U1snRNP70-Abs and smRNP-Abs. The bioplatform involves indirect immunoassays on the surface of magnetic microcarriers (independent batches for each of the target autoantibodies) and amperometric transduction using the H2O2/hydroquinone (HQ) system on a disposable multiple electrode platform. The magnetic microcarriers were modified with the corresponding antigens using His-tag and carbodiimide/succinimide chemistries and employed for the selective capture of the corresponding autoantibodies. Thereafter, they were enzymatically labelled with a secondary antibody conjugated with horseradish peroxidase (HRP) and magnetically captured on each of the working surfaces of the quadruple platform. The evaluation of the analytical and operational characteristics of the bioplatform for the amperometric determination of standards, performed under optimized experimental conditions, confirmed the bioplatform competitiveness in terms of sensitivity and point-of-care application compared to commercially available ELISA methodologies for the single determination of target Abs. The developed bioplatform was applied to the analysis of serum samples from healthy individuals and from patients with two prevalent autoimmune diseases (systemic lupus erythematosus, SLE, and Sjögren's syndrome, SS). The obtained results proved the potential of the bioplatform for the differential diagnosis of these two autoimmune diseases through the accurate, simple, and rapid multidetermination of the four target Abs.

High-Throughput Peptide Arrays Identify Potential Diagnostic Autoantibody Signatures in Early-Stage Lung Adenocarcinoma.

Early diagnosis is critical to lung adenocarcinoma patients' survival but faces inadequacies in convenient early detection. We applied a comprehensive microarray of 130,000 peptides to detect "autoantibody signature" that is autoantibodies binding to mimotopes for early detection of stage 0-I LUAD. Plasma samples were collected from 147 early-stage lung adenocarcinoma (Early-LUAD), 108 benign lung disease (BLD), and 122 normal healthy controls (NHC). Clinical characteristics, low-dose CT (LDCT), and laboratory tests were incorporated into correlation analysis. We identified 143 and 133 autoantibody signatures, distinguishing Early-LUAD from NHC/BLD in the discovery cohort. Autoantibody signatures significantly correlated with age, stage, tumor size, basophil count, and IgM level (P < 0.05). The random forest models based on differential autoantibody signatures displayed AUC of 0.92 and 0.87 to discern Early-LUAD from NHC/BLD in the validation cohort, respectively. Compared with LDCT, combining autoantibody signature and LDCT improved the positive predictive value from 50% to 78.33% (P = 0.049). In addition, autoantibody signatures displayed higher sensitivity of 72.4% to 81.0% compared with the combinational tumor markers (cyfra21.1, NSE, SCC, ProGRP) with a sensitivity of 22.4% (P = 0.000). Proteins matched by differential peptides were enriched in cancer-related PI3K/Akt, MAPK, and Wnt pathways. Overlaps between matched epitopes and autoantibody signatures illustrated the underlying engagement of autoantibodies in immune recognition. Collectively, autoantibody signatures identified by a high-throughput peptide microarray have the potential to detect Early-LUAD, which could assist LDCT to better diagnose Early-LUAD. Novel sensitive autoantibody signatures can adjuvant LDCT to better diagnose LUAD at very early stage.

Cross-sectional analysis reveals autoantibody signatures associated with COVID-19 severity.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is associated with increased levels of autoantibodies targeting immunological proteins such as cytokines and chemokines. Reports further indicate that COVID-19 patients may develop a broad spectrum of autoimmune diseases due to reasons not fully understood. Even so, the landscape of autoantibodies induced by SARS-CoV-2 infection remains uncharted territory. To gain more insight, we carried out a comprehensive assessment of autoantibodies known to be linked to diverse autoimmune diseases observed in COVID-19 patients in a cohort of 231 individuals, of which 161 were COVID-19 patients (72 with mild, 61 moderate, and 28 with severe disease) and 70 were healthy controls. Dysregulated IgG and IgA autoantibody signatures, characterized mainly by elevated concentrations, occurred predominantly in patients with moderate or severe COVID-19 infection. Autoantibody levels often accompanied anti-SARS-CoV-2 antibody concentrations while stratifying COVID-19 severity as indicated by random forest and principal component analyses. Furthermore, while young versus elderly COVID-19 patients showed only slight differences in autoantibody levels, elderly patients with severe disease presented higher IgG autoantibody concentrations than young individuals with severe COVID-19. This work maps the intersection of COVID-19 and autoimmunity by demonstrating the dysregulation of multiple autoantibodies triggered during SARS-CoV-2 infection. Thus, this cross-sectional study suggests that SARS-CoV-2 infection induces autoantibody signatures associated with COVID-19 severity and several autoantibodies that can be used as biomarkers of COVID-19 severity, indicating autoantibodies as potential therapeutical targets for these patients.

Autoantibody signatures discovered by HuProt protein microarray to enhance the diagnosis of lung cancer

This study aims to discover novel autoantibodies against tumor-associated antigens (TAAs) and establish diagnostic models for assisting in the diagnosis of lung cancer and discrimination of pulmonary nodules (PNs). Ten autoantibodies to TAAbs (TAAbs) were discovered by means of protein microarray and their serum level was also higher in 212 LC patients than that in 212 NC of validation cohort 1 (P < 0.05). The model 1 comprising 4 TAAbs and CEA reached an AUC of 0.813 (95%CI: 0.762–0.864) for diagnosing LC from normal individuals. Five TAAbs existed a significant difference between 105 malignant pulmonary nodules (MPNs) and 105 benign pulmonary nodules (BPNs) patients in validation cohort 2 (P < 0.05). Model 2 could distinguish MPNs from BPNs with an AUC of 0.845. High-throughput protein microarray is an efficient approach in discovering novel TAAbs which could be used as biomarkers in lung cancer diagnosis.

A protein microarray-based serum proteomic investigation reveals distinct autoantibody signature in colorectal cancer.

Colorectal cancer (CRC) has been reported as the second leading cause of cancer death worldwide. The 5-year annual survival is around 50%, mainly due to late diagnosis, striking necessity for early detection. This study aims to identify autoantibody in patients' sera for early screening of cancer. The study used a high-density human proteome array with approximately 17,000 recombinant proteins. Screening of sera from healthy individuals, CRC from Indian origin, and CRC from middle-east Asia origin were performed. Bio-statistical analysis was performed to identify significant autoantibodies altered. Pathway analysis was performed to explore the underlying mechanism of the disease. The comprehensive proteomic analysis revealed dysregulation of 15 panels of proteins including CORO7, KCNAB1, WRAP53, NDUFS6, KRT30, and COLGALT2. Further biological pathway analysis for the top dysregulated autoantigenic proteins revealed perturbation in important biological pathways such as ECM degradation and cytoskeletal remodeling etc. CONCLUSIONS AND CLINICAL RELEVANCE: The generation of an autoimmune response against cancer-linked pathways could be linked to the screening of the disease. The process of immune surveillance can be detected at an early stage of cancer. Moreover, AAbs can be easily extracted from blood serum through the least invasive test for disease screening.

Autoantibody profiling of monoamine oxidase A knockout mice, an autism spectrum disorder model

Monoamine oxidase A (MAO A) is the critical enzyme to degrade serotonin in the brain and the knockout mouse exhibits hyperserotonemia and abnormalities that are observed in autism spectrum disorder (ASD). Thus, the MAO A knockout mouse is a valuable model for studying neurological and behavioral impairments in ASD. Based on the immune dysfunction hypothesis, dysregulated humoral immunity may cause neurological impairments. To address this hypothesis, we use high-density proteome microarray to profile the serum antibodies in both wild-type and MAO A knockout mice. The distingue autoantibody signatures were observed in the MAO A knockout and wild-type controls and showed 165 up-regulated and 232 down-regulated autoantibodies. The up-regulated autoantibodies were prone to target brain tissues while down-regulated ones were enriched in sex organs. The identified autoantibodies help bridge the gap between ASD mouse models and humoral immunity, not only yielding insights into the pathological mechanisms but also providing potential biomarkers for translational research in ASD.

Selected Articles from This Issue

Previous treatment strategies for medulloblastoma have shown moderate improvement in response. However, the long-term overall survival remains disappointing, and many survivors have profound long-term complications. Therefore, there is a tremendous need to develop novel, improved, and safer therapeutic strategies for medulloblastoma. The critical tumor-stroma interactions mediated by the PlGF/NRP1 pathway make it an attractive target. Sholler and colleagues report a phase I, open-label, multicenter, dose-escalation study of the anti-PlGF antibody, TB-403, in pediatric subjects. TB-403 treatment was well tolerated and induced stable disease in high-risk, heavily pretreated relapsed medulloblastoma allowing for excellent quality of life. These findings indicate that treatment with TB-403 may represent a potentially transformative therapy for children with medulloblastoma and should be tested in larger studies.Costimulatory molecules expressed on the surface of T cells—such as 4-1BB, OX40, inducible T-cell costimulator (ICOS), and glucocorticoid-induced tumor necrosis factor receptor (GITR)—are potential targets to enhance T-cell antitumor activity. To evaluate the immunomodulatory effects of GITR agonist TRX518, Davar and colleagues designed a phase 1b study evaluating TRX518 alone and in combination with rational partners. While efficacy was modest, the authors consistently observed reductions in Tregs along with CD8+ T cell activation in responders. The pharmacodynamic effects of TRX518 upon Tregs suggests GITR agonism may require additional agents to effect greater Treg modulation and/or simultaneous targeting of alternative T-cell exhaustion pathways for clinical benefit.Desmoid fibromatosis (DF) is a rare disease affecting young adults. Spontaneous regression has been described in retrospective series. In this prospective observational study of 108 patients affected by primary sporadic DF primarily managed by active surveillance, Colombo and colleagues report the first prospective confirmation of spontaneous regression followed by regressions even after RECIST progression. They observed spontaneous regression in 56% of the patients (27/108 [25%] as an initial event plus 33/108 [31%] after initial progression). This supports active surveillance as the primary approach to the disease. Patients with larger tumors, extremity location and S45F beta-catenin mutations were at higher risk of receiving an active treatment and may deserve a more intense follow-up.Adjuvant immunotherapy produces durable benefit for patients with resected melanoma, but many develop recurrence and/or immune-related adverse events. In this study, Johannet and colleagues analyzed pre-treatment serum from 950 resected melanoma patients from two phase III randomized controlled trials of adjuvant immunotherapy: CheckMate 238 (ipilimumab vs nivolumab) and CheckMate 915 (nivolumab vs ipilimumab plus nivolumab). They identified autoantibody (autoAb) signatures for nivolumab, ipilimumab, and ipilimumab plus nivolumab that could be used to predict disease recurrence and severe immune-related adverse events. The composite panel of autoAb signatures can allow for the simultaneous risk stratification of patients according to their likelihood of recurring and suffering severe toxicity.

Baseline Serum Autoantibody Signatures Predict Recurrence and Toxicity in Melanoma Patients Receiving Adjuvant Immune Checkpoint Blockade.

Adjuvant immunotherapy produces durable benefit for patients with resected melanoma, but many develop recurrence and/or immune-related adverse events (irAE). We investigated whether baseline serum autoantibody (autoAb) signatures predicted recurrence and severe toxicity in patients treated with adjuvant nivolumab, ipilimumab, or ipilimumab plus nivolumab. This study included 950 patients: 565 from CheckMate 238 (408 ipilimumab versus 157 nivolumab) and 385 from CheckMate 915 (190 nivolumab versus 195 ipilimumab plus nivolumab). Serum autoAbs were profiled using the HuProt Human Proteome Microarray v4.0 (CDI Laboratories, Mayaguez, PR). Analysis of baseline differentially expressed autoAbs was followed by recurrence and severe toxicity signature building for each regimen, testing of the signatures, and additional independent validation for nivolumab using patients from CheckMate 915. In the nivolumab independent validation cohort, high recurrence score predicted significantly worse recurrence-free survival [RFS; adjusted HR (aHR), 3.60; 95% confidence interval (CI), 1.98-6.55], and outperformed a model composed of clinical variables including PD-L1 expression (P < 0.001). Severe toxicity score was a significant predictor of severe irAEs (aHR, 13.53; 95% CI, 2.59-86.65). In the ipilimumab test cohort, high recurrence score was associated with significantly worse RFS (aHR, 3.21; 95% CI, 1.38-7.45) and severe toxicity score significantly predicted severe irAEs (aHR, 11.04; 95% CI, 3.84-37.25). In the ipilimumab plus nivolumab test cohort, high autoAb recurrence score was associated with significantly worse RFS (aHR, 6.45; 95% CI, 1.48-28.02), and high severe toxicity score was significantly associated with severe irAEs (aHR, 23.44; 95% CI, 4.10-212.50). Baseline serum autoAb signatures predicted recurrence and severe toxicity in patients treated with adjuvant immunotherapy. Prospective testing of the signatures that include datasets with longer follow-up and rare but more severe toxicities will help determine their generalizability and potential clinical utility. See related commentary by Hassel and Luke, p. 3914.

Autoantibodies as Predictors for Clinical Outcome and Toxicity for Immunotherapy.

Peripheral blood autoantibody signatures might be useful biomarkers of immunotherapy outcome. Signatures predicting melanoma recurrence and toxicity during adjuvant immunotherapy were recently presented. Whether autoantibodies are bystanders or have a pathophysiologic role is unknown, and further efforts are needed to investigate potential mechanisms and determine causation. See related article by Johannet et al., p. 4121.