A review of cancer immunotherapy toxicity.

Cancer immunotherapies, including checkpoint inhibitors and adoptive cell therapy, manipulate the immune system to recognize and attack cancer cells. These therapies have the potential to induce durable responses in multiple solid and hematologic malignancies and thus have transformed treatment algorithms for numerous tumor types. Cancer immunotherapies lead to unique toxicity profiles distinct from the toxicities of other cancer therapies, depending on their mechanism of action. These toxicities often require specific management, which can include steroids and immune-modulating therapy and for which consensus guidelines have been published. This review will focus on the toxicities of checkpoint inhibitors and chimeric antigen receptor T cells, including pathophysiology, diagnosis, and management.

Effects of immune-related adverse events (irAEs) and their treatment on antitumor immune responses.

Immune checkpoint inhibitors (ICIs) are potentially life-saving cancer therapies that can trigger immune-related adverse events (irAEs). irAEs can impact any organ and range in their presentation from mild side effects to life-threatening complications. The relationship between irAEs and antitumor immune responses is nuanced and may depend on the irAE organ, the tumor histology, and the patient. While some irAEs likely represent an immune response against antigens shared between tumor cells and healthy tissues, other irAEs may be entirely unrelated to antitumor immune responses. Clinical observations suggest that low-grade irAEs have a positive association with responses to ICIs, but the correlation between severe irAEs and clinical benefit is less clear. Currently, severe irAEs are typically treated by interrupting or permanently discontinuing ICI treatment and administering empirically selected systemic immunosuppressive agents. However, these interventions could potentially diminish the antitumor effects of ICIs. Efforts to understand the mechanistic relationship between irAEs and the tumor microenvironment have yielded meaningful insights and nominated therapeutic targets for irAE management that may preserve or even boost ICI efficacy. We explore the clinical and molecular relationship between irAEs and antitumor immunity as well as the role that irAE treatments may play in shaping antitumor immune responses.

Tissue-resident memory T cells in immunotherapy and immune-related adverse events by immune checkpoint inhibitor.

Tissue-resident memory T cells (TRM) are a specialized subset of T cells that reside in tissues and provide long-term protective immunity against pathogens that enter the body through that specific tissue. TRM cells have specific phenotype and reside preferentially in barrier tissues. Recent studies have revealed that TRM cells are the main target of immune checkpoint inhibitor immunotherapy since their role in cancer immunosurveillance. Furthermore, TRM cells also play a crucial part in pathogenesis of immune-related adverse events (irAEs). Here, we provide a concise review of biological characteristics of TRM cells, and the major advances and recent findings regarding their involvement in immune checkpoint inhibitor immunotherapy and the corresponding irAEs.

Comparing anti-tumor and anti-self immunity in a patient with melanoma receiving immune checkpoint blockade.

BACKGROUND: Tumor regression following immune checkpoint blockade (ICB) is often associated with immune-related adverse events (irAEs), marked by inflammation in non-cancerous tissues. This study was undertaken to investigate the functional relationship between anti-tumor and anti-self immunity, to facilitate irAE management while promoting anti-tumor immunity. METHODS: Multiple biopsies from tumor and inflamed tissues were collected from a patient with melanoma experiencing both tumor regression and irAEs on ICB, who underwent rapid autopsy. Immune cells infiltrating melanoma lesions and inflamed normal tissues were subjected to gene expression profiling with multiplex qRT-PCR for 122 candidate genes. Subsequently, immunohistochemistry was conducted to assess the expression of 14 candidate markers of immune cell subsets and checkpoints. TCR-beta sequencing was used to explore T cell clonal repertoires across specimens. RESULTS: While genes involved in MHC I/II antigen presentation, IFN signaling, innate immunity and immunosuppression were abundantly expressed across specimens, irAE tissues over-expressed certain genes associated with immunosuppression (CSF1R, IL10RA, IL27/EBI3, FOXP3, KLRG1, SOCS1, TGFB1), including those in the COX-2/PGE2 pathway (IL1B, PTGER1/EP1 and PTGER4/EP4). Immunohistochemistry revealed similar proportions of immunosuppressive cell subsets and checkpoint molecules across samples. TCRseq did not indicate common TCR repertoires across tumor and inflammation sites, arguing against shared antigen recognition between anti-tumor and anti-self immunity in this patient. CONCLUSIONS: This comprehensive study of a single patient with melanoma experiencing both tumor regression and irAEs on ICB explores the immune landscape across these tissues, revealing similarities between anti-tumor and anti-self immunity. Further, it highlights expression of the COX-2/PGE2 pathway, which is known to be immunosuppressive and potentially mediates ICB resistance. Ongoing clinical trials of COX-2/PGE2 pathway inhibitors targeting the major COX-2 inducer IL-1B, COX-2 itself, or the PGE2 receptors EP2 and EP4 present new opportunities to promote anti-tumor activity, but may also have the potential to enhance the severity of ICB-induced irAEs.

Pituitary-related immune adverse events induced by programmed death Protein-1 inhibitors differ clinically from hypophysitis.

OBJECTIVE: We aimed to elucidate the clinical features of pituitary immune-related adverse events (irAEs) induced by PD-1 inhibitors in a Chinese cohort and the previous literatures. PATIENTS AND DESIGN AND MEASUREMENTS: We retrospectively analysed the clinical manifestations, laboratory examination findings, imaging features and treatments of 14 patients with pituitary irAEs caused by PD-1 inhibitors in our cohort. In addition, we searched PubMed for all English articles on pituitary irAEs induced by PD-1 inhibitors published from 1950 to 2023. A total of 47 articles were included, and the clinical characteristics of 94 patients with pituitary irAEs induced by PD-1 inhibitors in these literatures were compared to the characteristics of our cohort. RESULTS: Among the 14 patients in our cohort with pituitary irAEs induced by PD-1 inhibitors, 12 patients (85.71%, 12/14) exhibited isolated ACTH deficiency (IAD), 100.0% (14/14) of the central adrenocortical insufficiency, and 2 patients showed more than one hypothalamic-pituitary axis injury (14.29%, 2/14). Pituitary magnetic resonance imaging in all the 14 patients showed no pituitary enlargement. In previous studies we reviewed, 82.98% of the total (78/94) presented with pituitary irAEs as IAD, 100.0% (94/94) of the central adrenocortical insufficiency, and 78.33% of the patients showed no abnormality of the pituitary gland (47/60). The pituitary irAEs caused by PD-1 inhibitors did not involve typical manifestations of hypophysitis, such as pituitary enlargement, headache, visual field defects, and multiple pituitary function impairments in our cohort and the previous literatures. CONCLUSION: In our study, pituitary immune-related adverse reactions induced by PD-1 inhibitors mainly manifested isolated ACTH deficiency rather than hypophysitis.

Correlation between immune-related adverse events and efficacy of PD-(L)1 inhibitors in small cell lung cancer: a multi-center retrospective study.

BACKGROUND: Patients receiving PD-(L)1 inhibitors frequently encounter unusual side effects known as immune-related adverse events (irAEs). However, the correlation of irAEs development with clinical response in small cell lung cancer (SCLC) is unknown. METHOD: This retrospective study enrolled 244 stage IV SCLC patients who receiving PD-(L)1 inhibitors from 3 cancer centers. The correlation of irAEs with objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), and overall survival (OS) were evaluated. RESULTS: 140 in 244 (57%) patients experienced irAEs, with 122 (87.1%) experiencing one and 18 (12.9%) experiencing two or more. Compared to patient without irAEs, those developing irAEs had higher ORR (73.6% vs. 52.9%, P < 0.001) and DCR (97.9% vs. 79.8%, P < 0.001), as well as prolonged median PFS (8.8 vs. 4.5 months, P < 0.001) and OS (23.2 vs. 21.6 months, P < 0.05). Among the different spectra of irAEs, thyroid dysfunction, rash, and pneumonitis were the most powerful indicator for improved PFS. When analyzed as a time-dependent covariate, the occurrence of irAEs was associated with significant improvement in PFS rather than in OS. Furthermore, patients experiencing multisystem irAEs displayed a longer PFS and OS compared with single-system irAEs and the irAE-free ones. IrAEs grade and steroid use did not impact the predictive value of irAEs on PFS. CONCLUSION: The presence of irAEs predicts superior clinical benefit in SCLC. Patients who develop multi-system irAEs may have an improved survival than those developed single-system irAEs and no-irAEs. This association persists even when systemic corticosteroids were used for irAEs management.

Clinical characteristics and potential biomarkers of thyroid and pituitary immune-related adverse events.

Immune checkpoint inhibitors (ICIs) can cause immune-related adverse events (irAEs) in several organs including endocrine glands. Among endocrine irAEs, thyroid and pituitary irAEs are frequently observed, followed by primary adrenal insufficiency, insulin-dependent diabetes mellitus, and hypoparathyroidism. These conditions could lead to life-threatening consequences, such as adrenal crisis and diabetic ketoacidosis. On the other hand, several types of irAEs including thyroid and pituitary irAEs are reported to be associated with better overall survival. Therefore, it is important to understand and manage endocrine irAEs, which differ depending on the ICI regimen used. In this review, we describe the clinical features, potential biomarkers, management strategies, and possible mechanisms of thyroid and pituitary irAEs.

Development of Vogt-Koyanagi-Harada disease-like uveitis during treatment by anti-programmed death-1 antibody: a case report.

BACKGROUND: Several immune checkpoint inhibitors (ICIs) have been linked to the occurrence of Vogt-Koyanagi-Harada disease (VKHD)-like uveitis. Among the ICIs, there has been no report of immune-related adverse events (irAEs) caused by a new programmed death protein-1(PD-1) monoclonal antibody (Toripalimab). CASE PRESENTATION: This paper presents a case of VKHD-like uveitis that arose following Toripalimab therapy for urothelial cancer of the bladder, and the patient experienced symptoms 10 days after the final dosage of 20 months of medication treatment. This patient with bladder uroepithelial carcinoma had severe binocular acute panuveitis with exudative retinal detachment after receiving Toripalimab therapy. Binocular VKHD-like uveitis was suggested as a diagnosis. Both eyes recovered after discontinuing immune checkpoint inhibitors and local and systemic corticosteroid treatment. CONCLUSIONS: This report suggests that VKHD-like uveitis can also occur in patients receiving novel PD-1 antibodies and the importance of paying attention to eye complications in patients receiving treatment over a long period.

Digital ischemia: a rare immune-related adverse event of immune checkpoint inhibitors-case report and review of the literature.

Immune checkpoint inhibitors (ICIs) play a crucial role in treating various cancers. While ICIs are invaluable in the fight against different cancers, they also pose the risk of immune-related adverse events (irAEs), which can range widely in symptoms and severity. Rheumatologic complications, including digital ischemia, are among the irAEs. While rare, they require early detection for effective management. The aim of the study is to present a case report on digital ischemia related to immunotherapy and to conduct a literature review on relevant cases. We present a case involving a patient from our oncology department who developed, pericarditis, digital ischemia and anti-centromere antibodies during immunotherapy with pembrolizumab for non-small cell lung cancer (NSCLC). We collaborated with our rheumatology department to initiate treatment, including corticosteroids, iloprost, and mycophenolate mofetil. Through the follow-up, the patient showed clinical improvement. A literature review identified only 10 relevant articles, highlighting the rarity of digital ischemia as an irAE. Corticosteroids and vasodilators were commonly used treatments, with amputation unavoidable in 40% of cases. IrAEs are becoming more common due to the widespread use of ICIs. For this reason, it is crucial to diagnose and treat rare IrAEs, such as digital ischemia, as early as possible to improve outcomes.

Positron emission tomography molecular imaging to monitor anti-tumor systemic response for immune checkpoint inhibitor therapy.

Immune checkpoint inhibitors (ICIs) achieve a milestone in cancer treatment. Despite the great success of ICI, ICI therapy still faces a big challenge due to heterogeneity of tumor, and therapeutic response is complicated by possible immune-related adverse events (irAEs). Therefore, it is critical to assess the systemic immune response elicited by ICI therapy to guide subsequent treatment regimens. Positron emission tomography (PET) molecular imaging is an optimal approach in cancer diagnosis, treatment effect evaluation, follow-up, and prognosis prediction. PET imaging can monitor metabolic changes of immunocytes and specifically identify immuno-biomarkers to reflect systemic immune responses. Here, we briefly review the application of PET molecular imaging to date of systemic immune responses following ICI therapy and the associated rationale.

Prediction-based prompt levothyroxine replacement to prevent a hypothyroid state after immune-related adverse events involving the thyroid gland.

Immune checkpoint inhibitors (ICIs) are used for various malignancies, although they frequently cause immune-related adverse events involving the thyroid gland (thyroid irAEs). We conducted a retrospective cohort study to elucidate thyroid function outcomes. Fifty of 639 patients who received PD-1 blockade therapy met criteria and were divided into the following groups: thyrotoxicosis with subsequent hypothyroidism (Toxic-Hypo, n = 21); thyrotoxicosis without subsequent hypothyroidism (Toxic, n = 9); and hypothyroidism without prior thyrotoxicosis (Hypo, n = 20). The Toxic-Hypo group developed thyroid irAEs earlier than the Toxic group (26 vs. 91 days; p < 0.001), and had higher serum free T4 levels (3.210 vs. 1.880 ng/dL; p = 0.011). In addition, positive anti-thyroglobulin antibodies (TgAbs) at thyroid irAE onset were more common in the Toxic-Hypo group (93.3%) than in the Toxic group (0.0%; p = 0.005) and Hypo group (44.4%; p = 0.007). The Toxic-Hypo group developed severe hypothyroidism and required larger levothyroxine (LT4) doses than the Hypo group (75 vs. 25 µg/day; p = 0.007). We predicted that patients with positive TgAbs who developed severe thyrotoxicosis within 4 weeks after the first ICI administration would develop subsequent hypothyroidism. We treated 4 such patients with prompt LT4 replacement, characterized by LT4 initiation after thyrotoxicosis improvement and quick dose titration. Their euthyroid state was successfully maintained, in contrast with patients receiving conventional replacement. In conclusion, rapid-onset severe thyrotoxicosis in patients with TgAbs correlated with a high likelihood of subsequent hypothyroidism. Accordingly, prompt LT4 replacement is suggested to prevent a severely hypothyroid state.

A case of subclinical immune checkpoint inhibitor-associated myocarditis in non-small cell lung cancer.

BACKGROUND: Immune checkpoint inhibitors (ICIs) have been widely used in the treatment of cancer. Moreover, immune-related adverse events (irAEs) have become a new clinical challenge. ICI-associated myocarditis is a rare but fatal condition among diverse organ injuries, and early recognition and effective interventions are critical for patients. CASE PRESENTATION: In this report, we present the case of a healthy 60-year-old male who was diagnosed with lung squamous cell carcinomas following chemotherapy and received ICIs. The patient presented with asymptomatic cardiac biomarker elevation followed by immune-related myocarditis. Fortunately, the patient achieved a good clinical result after receiving high-dose steroids. The treatment with ICIs was discontinued because of recurrent increases in troponin T. CONCLUSION: ICI-mediated associated myocarditis is an uncommon but potentially life-threatening adverse event. The current data suggest that clinicians need to be cautious about reinitiation in low-grade patients; however, further study of the diagnosis and treatment is necessary.

Mechanisms underlying immune-related adverse events during checkpoint immunotherapy.

Immune checkpoint (IC) proteins are some of the most important factors that tumor cells hijack to escape immune surveillance, and inhibiting ICs to enhance or relieve antitumor immunity has been proven efficient in tumor treatment. Immune checkpoint blockade (ICB) agents such as antibodies blocking programmed death (PD) 1, PD-1 ligand (PD-L) 1, and cytotoxic T lymphocyte-associated antigen (CTLA)-4 have been approved by the U.S. Food and Drug Administration (FDA) to treat several types of cancers. Although ICB agents have shown outstanding clinical success, and their application has continued to expand to additional tumor types in the past decade, immune-related adverse events (irAEs) have been observed in a wide range of patients who receive ICB treatment. Numerous studies have focused on the clinical manifestations and pathology of ICB-related irAEs, but the detailed mechanisms underlying irAEs remain largely unknown. Owing to the wide expression of IC molecules on distinct immune cell subpopulations and the fact that ICB agents generally affect IC-expressing cells, the influences of ICB agents on immune cells in irAEs need to be determined. Here, we discuss the expression and functions of IC proteins on distinct immune cells and the potential mechanism(s) related to ICB-targeted immune cell subsets in irAEs.

Association between Changes in the Patterns of Antinuclear Autoantibodies during Immune Checkpoint Inhibition Therapy and the Development of Severe Immune Related Adverse Events.

Immune-related adverse events (irAEs) are unpredictable autoimmune-like toxicities induced by immune checkpoint inhibitors (ICI). irAEs are a consequence of a breakdown in self-tolerance. ICIs can induce autoantibody formation, and the presence of antinuclear autoantibodies (ANAs) has been reported in patients who developed irAEs. Our goal was to compare ANA patterns by indirect immunofluorescence at different timepoints before (baseline) and after the initiation of ICI treatment and to analyze the role of ANA pattern changes as predictors of irAEs. This is a 2-year-follow-up prospective study of 152 consecutive patients with solid tumors treated with anti-PD-(L)1 blockade agents. They were included from September 2018 until March 2020 in the Hospital de la Santa Creu I Sant Pau (Barcelona, Spain). We grouped patients into three groups: ANA de novo (patients who showed new ANA patterns at any time after ICI initiation), ANA (ANA positive at baseline without changes in the ANA patterns after initiation of treatment) and non-ANA (ANA negative at baseline and after ICI initiation). We did not find any association between the appearance of ANAs and irAE rates or the number and types of irAEs. However, patients in the ANA de novo group showed higher severe irAE rates (grade ≥ 3) than the other groups. Additionally, in most of the patients with severe irAEs (83.3%), changes in ANA patterns preceded irAE onset. In conclusion, we found ANA induction during ICI therapies in 22 patients and our results suggest that the appearance of ANAs may predict the severity of the irAE.

Immune-related adverse events (irAEs) in ankylosing spondylitis (AS) patients treated with interleukin (IL)-17 inhibitors: a systematic review and meta-analysis.

BACKGROUND: Ankylosing spondylitis (AS) is a chronic inflammatory rheumatic disease characterized by immune system dysregulation and inflammation in the joints. Interleukin (IL)-17 inhibitors are new biological drugs used to treat AS. In this study, we aimed to assess the risk of immune system-related AEs due to targeting IL-17 or IL-17R. METHODS: The CENTRAL, PubMed, Scopus, Google Scholar, Clinical Trials Registry, and ICTRP were searched for randomized clinical trials (RCTs) and non-RCTs until February 2021. The risk of irAEs in patients treated with IL-17 inhibitors compared to the placebo or a drug-free control was evaluated. In studies that reported AEs of the IL-17 inhibitors at several different time points, we compared the number of cases/100 patient-year in which irAEs were reported. Subgroup analyses were also performed based on the dose and type of drugs. RESULTS: Thirteen studies of 1848 AS patients treated by IL-17 inhibitors (secukinumab, ixekizumab, bimekizumab, and netakimab) and 764 participants who received a placebo were included. The risk of some AEs related to immune function in patients under IL-17 inhibitors treatment was significantly higher than that of the placebo group, including infection and infestation (risk difference RD = 0.09, P = 0.02), nasopharyngitis (RD = 0.04, P < 0.001), opportunistic infections (RD = 0.01, P = 0.04), and neutropenia (RD = 0.04, P = 0.03). Besides, the results of the Cochran Q test showed that there were significant differences between the occurrence of some AEs over time, including infection and infestations (p < 0.001, RCTs), upper respiratory tract infections (p < 0.001, non-RCTs), urinary tract infections (p < 0.001, non-RCTs), and diarrhea (p < 0.01, RCTs). CONCLUSIONS: The most common immune system-related AEs in patients treated with IL-17 inhibitors are mucosal and opportunistic infections.

Adverse cutaneous toxicities by PD-1/PD-L1 immune checkpoint inhibitors: pathogenesis, treatment, and surveillance.

INTRODUCTION: The therapeutic use of humanised monoclonal programmed cell death 1 (PD-1) (pembrolizumab, and nivolumab) and programmed cell death ligand-1 (PD-L1) (atezolizumab, avelumab, durvalumab) immune checkpoint inhibitors (ICPi) as potent anticancer therapies is rapidly increasing. The mechanism of signalling of anti-PD-1/PD-L1 involves triggering cytotoxic CD4+/CD8 + T cell activation and subsequent abolition of cancer cells which induces specific immunologic adverse events that are specific to these therapies. These drugs can cause numerous cutaneous reactions and are characterized as the most frequent immune-related adverse events (irAEs). Majority of cutaneous irAEs range from non-specific eruptions to detectible skin manifestations, which may be self-limiting and present acceptable skin toxicity profiles, while some may produce life-threatening complications. OBJECTIVE: This review aims to illuminate the associated cutaneous irAEs related to drugs used in oncology along with the relevant mechanism(s) and management. AREAS COVERED: Literature was searched using various databases including Pub-Med, Google Scholar, and Medline. The search mainly involved research articles, retrospective studies, case reports, and clinicopathological findings. With this review article, an overview of the cutaneous irAEs with anti-PD-1/PD-L1 therapy, as well as suggestions, have been provided, so that their recognition at early stages could help in better management and would prevent treatment discontinuation.HIGHLIGHTSCutaneous adverse effects are the most prevalent immune-related adverse events induced by anti-PD-1/PD-L1 immune-checkpoint antibodies.Cutaneous toxicities mainly manifest in the form of maculopapular rash and pruritus.More specific cutaneous complications can also occur, including vitiligo, worsened psoriasis, lichenoid dermatitis, mucosal involvement (e.g. oral lichenoid reaction), dermatomyositis, lupus erythematosus.Cutaneous manifestations can be life-threatening including Stevens-Johnson syndrome/toxic epidermal necrolysis (TEN).Dermatologic toxicities are usually mild, readily manageable, and rarely result in significant morbidity.Adequate management of the cutaneous adverse event and recognition in early stages could lead to the prevention of worsening of the lesions and limit treatment disruption.

Immune-related adverse events: promising predictors for efficacy of immune checkpoint inhibitors.

PURPOSE: This study was designed to investigate the correlation between immune-related adverse events (irAEs) of immune checkpoint inhibitors (ICIs) and corresponding efficacy, and to explore the potential of predicting the efficacy of ICIs via irAEs. METHODS: Electronic databases including PubMed, Embase, Cochrane Library, CNKI and Wanfang were applied to search for relevant studies. The primary endpoint was overall survival (OS) or progression-free survival (PFS), and the secondary endpoint was objective response rate (ORR). Stratification analyses were conducted according to the type of irAEs and ICIs, region of studies and primary tumors. Furthermore, statistical analyses were realized by means of RevMan 5.3 software. RESULTS: Altogether, 40 studies with 8,641 participants were enrolled, among which the incidence of irAEs ranged from 15.34 to 85.23% and the major sites reached out to skin, endocrine organ, gastrointestinal tract, liver and lung. The ORR, OS and PFS in irAE group were significantly higher than those in non-irAE group as per pooled analyses and stratification analyses. Importantly, patients with irAEs in skin, endocrine organ or gastrointestinal tract rather than in liver and lung were found to obtain survival benefits (p < 0.05). CONCLUSION: IrAEs, especially in skin, endocrine organ or gastrointestinal tract, triggered by ICIs indicate significant survival benefits.

Immune reconstitution and clinical recovery following anti-CD28 antibody (TGN1412)-induced cytokine storm.

Cytokine storm can result from cancer immunotherapy or certain infections, including COVID-19. Though short-term immune-related adverse events are routinely described, longer-term immune consequences and sequential immune monitoring are not as well defined. In 2006, six healthy volunteers received TGN1412, a CD28 superagonist antibody, in a first-in-man clinical trial and suffered from cytokine storm. After the initial cytokine release, antibody effect-specific immune monitoring started on Day + 10 and consisted mainly of evaluation of dendritic cell and T-cell subsets and 15 serum cytokines at 21 time-points over 2 years. All patients developed problems with concentration and memory; three patients were diagnosed with mild-to-moderate depression. Mild neutropenia and autoantibody production was observed intermittently. One patient suffered from peripheral dry gangrene, required amputations, and had persistent Raynaud's phenomenon. Gastrointestinal irritability was noted in three patients and coincided with elevated γδT-cells. One had pruritus associated with elevated IgE levels, also found in three other asymptomatic patients. Dendritic cells, initially undetectable, rose to normal within a month. Naïve CD8+ T-cells were maintained at high levels, whereas naïve CD4+ and memory CD4+ and CD8+ T-cells started high but declined over 2 years. T-regulatory cells cycled circannually and were normal in number. Cytokine dysregulation was especially noted in one patient with systemic symptoms. Over a 2-year follow-up, cognitive deficits were observed in all patients following TGN1412 infusion. Some also had signs or symptoms of psychological, mucosal or immune dysregulation. These observations may discern immunopathology, treatment targets, and long-term monitoring strategies for other patients undergoing immunotherapy or with cytokine storm.

Patients with gastrointestinal irritability after TGN1412-induced cytokine storm displayed selective expansion of gut-homing αß and γδT cells.

Following infusion of the anti-CD28 superagonist monoclonal antibody TGN1412, three of six previously healthy, young male recipients developed gastrointestinal irritability associated with increased expression of 'gut-homing' integrin ß7 on peripheral blood αßT cells. This subset of patients with intestinal symptoms also displayed a striking and persistent expansion of putative Vδ2+ γδT cells in the circulation which declined over a 2-year period following drug infusion, concordant with subsiding gut symptoms. These data demonstrate that TGN1412-induced gastrointestinal symptoms were associated with dysregulation of the 'gut-homing' pool of blood αß and γδT cells, induced directly by the antibody and/or arising from the subsequent cytokine storm.

Preexisting autoimmune disease is a risk factor for immune-related adverse events: a meta-analysis.

PURPOSE: Patients with preexisting autoimmune disease (PAD) are often excluded from clinical trials assessing immune checkpoint inhibitors (ICIs). Therefore, the safety of ICI therapy in patients with PAD remains unclear. Herein, we evaluated the incidence of immune-related adverse events (irAEs) in patients with PAD when compared with non-PAD patients. METHODS: We searched MEDLINE/PubMed, Web of Science, and Google Scholar for eligible studies from inception to January 2021. Observational studies reporting the incidence of irAEs in patients with and without PAD were included. We then performed a meta-analysis of eligible studies using forest plots. The primary endpoint of this study was the incidence rate of irAEs between patients with and without PAD. RESULTS: We identified three prospective and three retrospective studies involving 206 patients with PAD and 3078 patients without PAD. In the meta-analysis, 128 patients with PAD (62.1%) experienced irAEs, which occurred in 51.9% of non-PAD patients, resulting in an odds ratio (OR) of 2.14 (95% confidence interval [CI] 1.58-2.89). In the subgroup analysis, the incidence of irAEs was significantly higher in patients with PAD (OR = 2.19, 95% CI [1.55-3.08]). Furthermore, no significant heterogeneity or publication bias was detected, indicating that our meta-analysis could be generalized to clinical settings. CONCLUSION: This meta-analysis demonstrated that PAD was a risk factor for irAE incidence. These results suggest that monitoring the occurrence of irAEs in patients with PAD is required to manage irAEs appropriately.