Diabetes mellitus secondary to treatment with immune checkpoint inhibitors

The Development of Diabetes and Diabetic Ketoacidosis Following Immunotherapy Treatment: A Systematic Review of Case Reports

As cancer continues to be the leading cause of death worldwide, additional therapeutic options other than traditional platinum-based chemotherapy have become available that target tumor cells in innovative ways. Immunotherapies (e.g., immune checkpoint inhibitors (ICI)) ramp up the immune system to target cancer cells, providing patients with more personalized and tumor cell-specific treatment options. This new age oncological treatment option has been found to provide a more meaningful and stronger alternative to traditional chemotherapy, resulting in longer periods of remission and milder side effects. However, because ICI heightens the immune system, resultant autoimmune conditions can occur. One of the most recently shown adverse effects of ICI are extreme hyperglycemia (i.e., type 1 diabetes) and diabetic ketoacidosis (DKA). To determine the incidence of immunotherapy-induced diabetes, a systematic literature review was performed using CINHAL, EBSCO, MEDLINE, and Web of Science. A total of 403 articles were initially screened, with a final 28 case reports included. The results show that checkpoint inhibitors were found to be most commonly associated with new-onset diabetes as opposed to traditional chemotherapy. Additionally, 41% of patients developed autoimmune diabetes and DKA after being placed on a single therapy of pembrolizumab (targets PD-1: programmed cell death protein 1). However, the pathological process underlying the development of endocrinopathies after treatment with ICI continues to be under investigation.

Clinically Approved Monoclonal Antibodies-based Immunotherapy: Association With Glycemic Control and Impact Role of Clinical Pharmacist for Cancer Patient Care

PURPOSE

Compared with more conventional, nonspecific therapy options, such as radiotherapy and chemotherapy, monoclonal antibodies (mAbs) constitute a crucial approach of cancer treatment. Multiple autoimmune diseases have been observed during treatment with mAb medications, including autoimmune diabetes mellitus (DM). This study provides a narrative review of clinically approved mAbs in cancer treatment and focuses on the development of hyperglycemia and DM arising from using these therapies. Furthermore, it highlights the critical role of oncology clinical pharmacists in the management of autoimmune DM and patient care while using these medications in an oncology setting.

METHODS

An extensive literature search was conducted using various sources of electronic databases, such as Scopus, Embase, Web of Science, and PubMed, and search engines, such as Google Scholar, for studies on mAb classification, types, mechanisms of action, pharmacokinetic properties, current clinical applications, and the associated common adverse effects with significant recommendations for patient care in an oncology setting, along with focusing on the proposed mechanisms and clinical studies that reported the association of DM after the use of these therapies.

FINDINGS

There are 4 types (murine, chimeric, humanized, and human) and 3 classes (unconjugated, conjugated, and bispecific) of mAbs with several mechanisms of action that can destroy cancer cells, including preventing tumor cell survival cascades, inhibiting tumor growth by interfering with tumor angiogenesis, evading programmed cell death, and bypassing immune checkpoints. However, multiple endocrinopathies, autoimmune diseases, and complications were reported from the use of these medications, including the development of autoimmune DM and diabetic ketoacidosis. These autoimmune disorders were reported most with the use of immune checkpoint inhibitors, including inhibitors of the programmed cell death protein 1 (nivolumab and pembrolizumab), its ligand (atezolizumab, avelumab, and durvalumab), and cytotoxic T-lymphocyte-associated protein 4 (ipilimumab).

IMPLICATIONS

mAbs are considered important approaches for the treatment of many cancer types. However, a high incidence of hyperglycemia, type 1 DM, and diabetic ketoacidosis is observed with the use of these medications, particularly immune checkpoint inhibitors. It is important for oncologic clinical pharmacists to be involved in addressing these autoimmune disorders from the use of these immunotherapies via the provision of patient education, medication adherence support, close monitoring, and follow-up, which will lead to better health-related outcomes and improved patient quality of life.

Successful treatment of nivolumab and ipilimumab triggered type 1 diabetes by using sodium-glucose transporter 2 inhibitor: a case report and systematic review

Objective

Checkpoint inhibitors (CPIs) can trigger complications related to the autoimmune process such as CPI-triggered diabetes mellitus. The typical treatment for CPI-triggered diabetes is insulin, but a detailed therapeutic method has not yet been established. To prevent severe symptoms and mortality of diabetic ketoacidosis in advanced-stage cancer patients, the establishment of effective treatment of CPI-triggered diabetes, other than insulin therapy, is required.

Methods

We present a case of a 76-year-old man with CPI-triggered diabetes who was treated with nivolumab and ipilimumab for lung cancer. We also conducted a systematic review of 48 case reports of type 1 diabetes associated with nivolumab and ipilimumab therapy before June 2023.

Results

The patient's hyperglycemia was not sufficiently controlled by insulin therapy, and after the remission of ketoacidosis, the addition of a sodium-glucose transporter (SGLT) 2 inhibitor, dapagliflozin, improved glycemic control. Most of the reported nivolumab/ipilimumab-induced type 1 diabetes was treatable with insulin, but very few cases required additional oral anti-diabetic agents to obtain good glucose control.

Conclusion

Although SGLT2 inhibitors have been reported to have adverse effects on ketoacidosis, recent studies indicate that the occurrence of ketoacidosis is relatively rare. Considering the pathological mechanism of CPI-triggered diabetes, SGLT2 inhibitors could be an effective choice if they are administered while carefully monitoring the patient's ketoacidosis.

A comprehensive review on immune checkpoint inhibitors induced cardiotoxicity characteristics and associated factors

Newly approved cancer drugs called ICIs have shown remarkable success in improving patient survival rates, but they also have the potential for inflammatory and immune-related side effects, including those affecting the cardiovascular system. Research has been conducted to understand the development of these toxicities and identify risk factors. This review focuses on the characteristics of ICI-induced cardiotoxicity and discusses the reported risk factors. It is important for cardio-oncologists to understand the basic concepts of these drugs to better understand how cardiotoxicities occur. It might be hard to find reports, where all patients treated with ICIs had developed cardiac toxicity, because there could be other existing and variable factors that influence the likelihood or risk of developing cardiotoxicity during treatment. Various clinical parameters have been explored as potential risk factors, and further investigation is needed through large-scale studies.

Clinical outcomes of immune checkpoint inhibitor diabetes mellitus at a comprehensive cancer center

Introduction: Immune checkpoint inhibitor-associated diabetes mellitus (ICI-DM) is a rare adverse event. In this study, we characterize clinical outcomes of patients with ICI-DM and evaluate survival impact of this complication on melanoma patients. Research design & methods: We conducted a retrospective review of 76 patients diagnosed with ICI-DM from April 2014 to December 2020. Results: 68% of patients presented in diabetic ketoacidosis, 16% had readmissions for hyperglycemia, and hypoglycemia occurred in 70% of patients after diagnosis. Development of ICI-DM did not impact overall survival or progression-free survival in melanoma patients. Conclusion: Development of ICI-DM is associated with long-term insulin dependence and pancreatic atrophy; the use of diabetes technology in this patient population can help improve glycemic control.

Clinical and immunological characteristics of PD-1 associated fulminant type 1 diabetes mellitus

OBJECTIVES

Programmed death 1 (PD-1) associated fulminant type 1 diabetes (PFD) is a rare acute and critical in internal medicine, and its clinical characteristics are still unclear. This study aims to analyze the clinical characteristics of PFD patients to improve clinical diagnosis and treatment.

METHODS

We retrospectively analyzed the clinical data of 10 patients with PFD admitted to the Second Xiangya Hospital of Central South University, combined with the data of 66 patients reported in the relevant literature, analyzed and summarized their clinical and immunological characteristics, and compared the patients with PFD with different islet autoantibody status.

RESULTS

Combined with our hospital and literature data, a total of 76 patients with PFD were reported, with the age of (60.9±12.1) years old, 60.0% male and body mass index of (22.1±5.2) kg/m2. In 76 patients, the most common tumors were lung cancer (43.4%) and melanoma (22.4%). Among PD-1 inhibitors, the most common drugs are nivolumab (37.5%) and pembrolizumab (38.9%). 82.2% of PFD patients developed diabetes ketoacidosis. The median onset time from PD-1 related inhibitor treatment to hyperglycemia was 95 (36.0, 164.5) d, and the median treatment cycle before the onset of diabetes was 6 (2.3, 8.0) cycles. 26% (19/73) of PFD patients had positive islet autoantibodies, and the proportion of ketoacidosis in the positive group was significantly higher than that in the negative group (100.0% vs 75.0%, P<0.05). The onset time and infusion times of diabetes after PD-1 inhibitor treatment in the autoantibody positive group were significantly lower than those in the autoantibody negative group (28.5 d vs 120.0 d; 2 cycles vs 7 cycles, both P<0.001).

CONCLUSIONS

After initiation of tumor immunotherapy, it is necessary to be alert to the occurrence of adverse reactions of PFD, and the onset of PFD with islet autoantibody positive is faster and more serious than that of patients with autoantibodies negative. Detection of islet autoantibodies and blood glucose before and after treatment with PD-1 inhibitors is of great value for early warning and prediction of PFD.

Increased risk of incident diabetes after therapy with immune checkpoint inhibitor compared with conventional chemotherapy: A longitudinal trajectory analysis using a tertiary care hospital database

AIMS/HYPOTHESIS

Immune checkpoint inhibitor (ICI) has been emerged as a promising cancer treatment. However, ICI use induces immune-related adverse events, including diabetes mellitus. We compared the risk of new-onset diabetes between patients receiving an ICI and those receiving conventional chemotherapy (CC).

METHODS

Using a tertiary care hospital database, we included cancer patients without a previous history of diabetes who were treated with either CC or an ICI. One-to-five nearest neighbor propensity matching was applied, and the risk of diabetes was estimated using a Cox proportional hazards model. Latent class growth modeling was performed with a trajectory approach to determine distinct clusters that followed similar glucose trajectory patterns over time.

RESULTS

Among 1326 subjects, 1105 received CC, and 221 received an ICI. The risk of new-onset diabetes was significantly higher in the ICI group than the CC group (adjusted hazard ratio 2.454, 95 % confidence interval 1.528-3.940; p < 0.001). The ICI group had a higher proportion of subjects in the trajectory cluster with an increasing glucose pattern than the CC group (10.4 % and 7.4 %, respectively). Within the ICI group, the subjects with an increasing glucose pattern were predominantly male and associated with enhanced lymphocytosis after ICI administration.

CONCLUSIONS

ICI therapy is associated with an increased risk of incident diabetes compared with CC. The glucose levels of patients treated with an ICI, especially males and those with prominent lymphocytosis after ICI treatment, need to be monitored regularly to detect ICI-associated diabetes as early as possible.

Type 1 diabetes mellitus induced by PD-1 inhibitors in China: a report of two cases

The immune-related adverse events associated with immunotherapy may affect endocrine glands and other tissues. Two Chinese patients with malignancies were treated with programmed cell death-1 (PD-1) inhibitors (nivolumab and pembrolizumab) and followed up with biochemical tests over 1 year. After PD-1 treatment for 6 to 10 months, the patients developed symptoms of diabetes, ketoacidosis, and insulin secretion failure. Type 1 diabetes mellitus was confirmed by the characteristic fluctuation of blood glucose that was controlled with multiple daily insulin injections. Neither patient’s insulin depletion status was reversed in subsequent years. To decrease the life-threatening complications of diabetic hyperosmolar syndrome and ketoacidosis caused by type 1 diabetes mellitus, it is necessary to monitor the blood glucose and hemoglobin A1c levels. Islet β-cell autoantibodies and human leukocyte antigen genes can provide additional information in select cases.

Clinical characteristics and outcomes of immune checkpoint inhibitor-induced diabetes mellitus

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This article summarized a total of 172 published cases of immune checkpoint inhibitor (ICI)-induced diabetes mellitus (DM).

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Found that glutamic acid decarboxylase antibodies positivity is related to an earlier onset of ICI-induced diabetes and a higher frequency of diabetic ketoacidosis development.

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Presented a case of ICI-induced DM following obvious lipase and amylase elevation and discussed possible relationship between ICI-associated injuries to pancreatic exocrine function and endocrine function.

Objective

To better understand immune checkpoint inhibitor (ICI)-induced diabetes mellitus (DM) in cancer patients.

Design and method

We present a case of ICI-induced diabetic ketoacidosis (DKA) and conduct a systematic review of the PubMed and Web of Science databases up to September 2021 to identify all published cases of ICI-induced diabetes.

Results

In addition to our case, a total of 171 published cases were identified during the literature search. Summary and statistical analyzes were conducted for all 172 cases. The median onset time from ICI initiation to DM diagnosis was 12 weeks (range: 0–122). DKA was present in 67.4% (116/172) of the cases, and low C-peptide levels were detected in 91.8% (123/134), indicating an acute onset of diabetes. Patients with positive glutamic acid decarboxylase antibodies (GADA) had an earlier onset of ICI-induced diabetes (median time 7 weeks vs. 16 weeks for GADA-negative patients, p < 0.001) and a higher frequency of DKA development (82.8 vs. 62.1%, p = 0.006). All but two patients developed insulin-dependent diabetes permanently. Immunotherapy rechallenge was reported in 53 cases after glycemia was well controlled.

Conclusion

ICI-induced DM is a serious adverse event that often presents with life-threatening ketoacidosis. GADA positivity is related to an earlier onset of ICI-induced diabetes and a higher frequency of DKA development. Close monitoring of glucose levels is needed in patients receiving ICI treatment. ICI-induced DM is usually insulin-dependent since damage to β cells is irreversible. On the premise of well-controlled glycemia, immunotherapy rechallenge is feasible.

The genetic influence of PD-1/PD-L1 axis single nucleotide polymorphisms on the incidence of type 1 diabetes mellitus in pediatric Egyptian patients

Background

The increasing prevalence of diabetes mellitus (DM) is one of the most challenging public health issues. The destruction of insulin-producing cells in the islets of Langerhans is the hallmark of type 1 diabetes mellitus (T1DM) as an autoimmune disease. In the current case–control study, the role of single nucleotide polymorphisms (SNPs) was investigated within the programmed death-1 (PD-1)/programmed death ligand-1 (PD-L1) inhibitory axis and their association with T1DM susceptibility in a sample of Egyptian pediatric patients. The study included 80 T1DM pediatric patients and 76 healthy control subjects. The patients were recruited from Beni-Suef University Hospital’s Pediatric Endocrinology Outpatient Clinic. Genotyping of PD-1 SNP (rs 34819629) and PD-L1 SNPs (rs 2297137 and rs 4143815) was performed by TaqMan allelic discrimination technique via real-time polymerase chain reaction (RT-PCR). The patients were subjected to a thorough clinical examination and history taking.

Result

Genotyping of PD-1 (rs 34819629) revealed that all of the enrolled patients and the control group inherited the same genotype (GG genotype). With regard to PDL-1 rs4143815 SNP and the risk of T1DM occurrence, our comparison did not reveal the presence of an association between the different genetic models (general, dominant, and recessive) of the SNP and the risk of T1DM (p = 0.078 and p = 0.055; for the general genetic model, p = 0.061 and p = 0.169 for the dominant and the recessive types, respectively). Regarding PDL-1 rs2297137 SNP, the results of this study demonstrated that the risk of T1DM was significantly associated with the recessive genetic model (p = 0.007) as the diabetic group’s predominant G allele was higher compared to the control group.

Conclusion

The findings obtained supported the hypothesis that the predominant G allele of PD-L1 rs2297137 is associated with the development of T1DM. Chronic hyperglycemia and long-standing diabetes problems are linked to both PD-L1 SNPs (rs4143815 and rs2297137). Future studies with a more significant number of patients are required to support our results.

Cutting Edge: Enhanced Antitumor Immunity in ST8Sia6 Knockout Mice

Inhibitory receptors have a critical role in the regulation of immunity. Siglecs are a family of primarily inhibitory receptors expressed by immune cells that recognize specific sialic acid modifications on cell surface glycans. Many tumors have increased sialic acid incorporation. Overexpression of the sialyltransferase ST8Sia6 on tumors led to altered immune responses and increased tumor growth. In this study, we examined the role of ST8Sia6 on immune cells in regulating antitumor immunity. ST8Sia6 knockout mice had an enhanced immune response to tumors. The loss of ST8Sia6 promoted an enhanced intratumoral activation of macrophages and dendritic cells, including upregulation of CD40. Intratumoral regulatory T cells exhibited a more inflammatory phenotype in ST8Sia6 knockout mice. Using adoptive transfer studies, the change in regulatory T cell phenotype was not cell intrinsic and depended on the loss of ST8Sia6 expression in APCs. Thus, ST8Sia6 generates ligands for Siglecs that dampen antitumor immunity.

An Unusual Etiology of Hypothyroidism and New-Onset Insulin-Dependent Diabetes: A Rare Side Effect of Nivolumab

Nivolumab, a monoclonal antibody targeting programmed cell death 1 receptor, is prescribed for many advanced cancers like malignant melanoma, non-small cell lung cancer, renal cell cancer, etc. With the increase in the use of nivolumab like immunotherapy, the incidences of immune-related side effects are also on the rise. Immune-related endocrinopathies like hypothyroidism and new-onset type 2 diabetes mellitus associated with nivolumab use, although rare, are already documented in the literature. Here we present a case of hypothyroidism and new-onset type 2 diabetes mellitus in a renal cell cancer patient receiving nivolumab for the past six months. The patient was managed successfully with discontinuation of nivolumab, intravenous insulin, and thyroid hormone replacement therapy. These types of endocrinopathies can be fatal; hence, prompt diagnosis and management are required. Thus, not only physicians' awareness of such endocrinopathies among nivolumab-treated patients but also patients' awareness regarding warning signs and symptoms are essential.

Hyperosmolar Hyperglycaemic State and Diabetic Ketoacidosis in Nivolumab-Induced Insulin-Dependent Diabetes Mellitus

Nivolumab is a monoclonal antibody directed against programmed cell death-1 receptor. It has an increasing application in the treatment of various advanced metastatic cancers. The incidence of autoimmune side effects associated with such agents is expected to increase. New-onset autoimmune diabetes mellitus associated with immune checkpoint inhibitor treatment is rare, occurring in less than 1% of patients. Nivolumab-induced diabetes often presents as diabetic ketoacidosis, which could be life-threatening if not recognized and treated promptly. We present the case of a patient who developed severe diabetic ketoacidosis concomitant with hyperosmolar hyperglycaemic state (HHS) after receiving nivolumab for metastatic testicular lymphoma. Pre-nivolumab blood glucose levels were normal, apart from transient hyperglycaemia related to steroids as part of the chemotherapy protocol. The diagnosis was confirmed with extremely low C-peptide in the clinic.

LEARNING POINTS

Checkpoint inhibitor-associated diabetes can present abruptly with life-threatening complications.Most patients require multiple daily injections of insulin upon discharge.Cessation of checkpoint inhibitor therapy does not revert diabetes.

The influence of monoclonal antibodies for cancer treatment on the endocrine system

Cancer is one of the main causes of mortality worldwide. Thanks to scientific research, new methods of cancer treatment, including molecularly targeted therapy, are being developed. Monoclonal antibodies are used to treat many diseases, including some types of cancer, and affect various systems of the human body. The presented article aims to present the adverse effects of molecularly targeted cancer therapy on the endocrine system based on the current literature data. Immune checkpoint inhibitors, such as anti-CTLA-4 and anti-PD-1 or its ligand PD-L1, can cause a variety of autoimmune adverse effects, among others, thyroid dysfunction, hypophysitis, and diabetes mellitus. The authors also paid attention to monitoring selected diagnostic parameters to prevent endocrine adverse effects during a therapy with monoclonal antibodies. The development of adverse effects may sometimes progress atypically and rapidly, and may be a life-threatening condition. Clinicians should choose individual schemes of treatment for particular patients. The patient’s condition should also be monitored before, during and after the therapy. The decision about the continuation of treatment with monoclonal antibodies should be based especially on a risk connected with the cessation of treatment. Clinical trials should be continued to improve knowledge about the side effects of monoclonal antibodies.

Metabolic and Nutritional Disorders Following the Administration of Immune Checkpoint Inhibitors: A Pharmacovigilance Study

BACKGROUND

Although several metabolic and nutritional disorders (MNDs) have been reported in the recipients of immune checkpoint inhibitors (ICIs), these events have not been fully captured and comprehensively characterized in real-world population.

OBJECTIVES

To provide complete metabolic and nutritional toxicity profiles after ICIs (single and combined) initiation through an integrated big database.

METHODS

Reporting odds ratios (ROR) and information component (IC) based on statistical shrinkage transformation were utilized to perform disproportionality analysis using the US Food and Drug Administration Adverse Events Reporting System. Both ROR and IC were used to calculate disproportionality when compared with the whole database, but only ROR was used when comparison was made for different ICI strategies. Only when both the lower limits of 95% confidence intervals (CIs) for ROR (ROR₀₂₅) and IC (IC₀₂₅) exceeded specified threshold values (1 and 0, respectively) was regarded as a signal.

RESULTS

A total of 29,294,335 records were involved and 8,662 records were for MNDs in patients exposed to ICIs. Statistically significant association was detected between ICIs use and total MNDs (IC₀₂₅/ROR₀₂₅ = 1.06/2.19). For monotherapy, three ICI monotherapies (anti-PD-1, anti-PDL-1, and anti-CTLA-4) were all disproportionately associated with MNDs. Statistically significant differences in reporting frequencies also emerged when comparing anti-PD-1 with anti-PD-L1/anti-CTLA-4 monotherapy, with RORs of 1.11 (95%CI 1.01-1.21), and 1.35 (95%CI 1.23-1.48), respectively. Notably, combination therapy was associated with a higher reporting frequency of theses toxicities compared to monotherapy with a ROR of 1.56 (95%CI 1.48-1.64). Additionally, disproportionality analysis at High-level Group Term level highlighted eight broad entities of MNDs. Further disproportionality analysis at Preferred Term level indicated a wide range and varied strength of signals. For ICI monotherapy, nivolumab and pembrolizumab showed the broadest spectrum of MNDs. For combination therapy, a variety of signals were detected for nivolumab + ipilimumab therapy even comparable to two PD-1 monotherapies.

CONCLUSION

Metabolic and nutritional complications could be provoked by ICI monotherapy (especially anti-PD-1) and further reinforced by combination therapy. Clinicians and patients should be informed about these potential risks that might be encountered in real-world practice. Aforehand education and regular monitoring of related biochemical parameters (calcium, sodium, potassium, protein) are recommended to ensure better cancer survivorship.

Caring for Hospitalized Patients with Diabetes Mellitus, Hyperglycemia, and COVID-19: Bridging the Remaining Knowledge Gaps

PURPOSE OF REVIEW

This review discusses the interplay between coronavirus disease 2019 (COVID-19, caused by SARS-CoV-2 infection), diabetes mellitus, and hyperglycemia in the hospital setting. There are data emerging about diabetes and hyperglycemia, their prevalence, and potential risks in the setting of SARS-CoV-2 infection and COVID-19.

RECENT FINDINGS

It is known that viral infections exert effects on beta cell function and insulin resistance. Therefore, much can be learned about SARS-CoV-2/COVID-19 from examining these known relationships. Such pathophysiological underpinnings may unlock greater understanding as we navigate atypical cases of hyperglycemia, severe insulin resistance, and diabetic ketoacidosis amidst COVID-19. Glycemic outcomes likely have beneficial effects on morbidity and mortality, but this needs to be studied. Changes in diabetes-related protocols and new technology can be deployed in the inpatient setting to potentially improve healthcare worker and patient safety; however, one must weigh the risks and benefits of implementation during a pandemic. Ultimately, knowledge and research must be shared at record speed to combat this global crisis.

The Confounders of Cancer Immunotherapy: Roles of Lifestyle, Metabolic Disorders and Sociological Factors

Checkpoint blockade immunotherapy (CPI) is an effective treatment option for many types of cancers. Irrespective of its wide clinical implications, the overall efficacy remains unpredictable and even poor in certain pathologies such as breast cancer. Thus, it is imperative to understand the role of factors affecting its responsiveness. In this review, we provide an overview on the involvement of sociological factors, lifestyles and metabolic disorders in modulating the CPI response in patients from multiple malignancies. Lifestyle habits including exercise, and diet promoted therapeutic responsiveness while alcohol consumption mitigated the CPI effect by decreasing mutational burden and hampering antigen presentation by dendritic cells. Metabolic disorder such as obesity was recognized to enhance the PD-1 expression while diabetes and hypertension were consequences of CPI therapy rather than causes. Among the sociologic factors, sex and race positively influenced the CPI effectiveness on account of increased effector T cell activity and increased PD-1 expression while ageing impaired CPI responsiveness by decreasing functional T cell and increased toxicity. The combined effect of these factors was observed for obesity and gender, in which obese males had the most significant effect of CPI. Therefore these variables should be carefully considered before treating patients with CPI for optimal treatment outcome.

Interleukin-15 in autoimmunity

Interleukin-15 (IL-15) is a member of the IL-2 family of cytokines, which use receptor complexes containing the common gamma (γ_c) chain for signaling. IL-15 plays important roles in innate and adaptative immune responses and is implicated in the pathogenesis of several immune diseases. The IL-15 receptor consists of 3 subunits namely, the ligand-binding IL-15Rα chain, the β chain (also used by IL-2) and the γ_c chain. IL-15 uses a unique signaling pathway whereby IL-15 associates with IL-15Rα during biosynthesis, and this complex is 'trans-presented' to responder cells that expresses the IL-2/15Rβγ_c receptor complex. IL-15 is subject to post-transcriptional and post-translational regulation, and evidence also suggests that IL-15 cis-signaling can occur under certain conditions. IL-15 has been implicated in the pathology of various autoimmune diseases such as rheumatoid arthritis, autoimmune diabetes, inflammatory bowel disease, coeliac disease and psoriasis. Studies with pre-clinical models have shown the beneficial effects of targeting IL-15 signaling in autoimmunity. Unlike therapies targeting other cytokines, anti-IL-15 therapies have not yet been successful in humans. We discuss the complexities of IL-15 signaling in autoimmunity and explore potential immunotherapeutic approaches to target the IL-15 signaling pathway.

Role of the PD-1/PD-L1 Dyad in the Maintenance of Pancreatic Immune Tolerance for Prevention of Type 1 Diabetes

The human pancreas, like almost all organs in the human body, is immunologically tolerated despite the presence of innate and adaptive immune cells that promptly mediate protective immune responses against pathogens in situ. The PD-1/PD-L1 inhibitory pathway seems to play a key role in the maintenance of immune tolerance systemically and within the pancreatic tissue. Tissue resident memory T cells (TRM), T regulatory cells (Treg), macrophages and even β cells exhibit PD-1 or PD-L1 expression that contributes in controlling pancreatic immune homeostasis and tolerance. Dysregulation of the PD-1/PD-L1 axis as shown by animal studies and our recent experience with checkpoint inhibitory blockade in humans can lead to immune dysfunctions leading to chronic inflammatory disease and to type 1 diabetes (T1D) in genetically susceptible individuals. In this review, we discuss the role of the PD-1/PD-L1 axis in pancreatic tissue homeostasis and tolerance, speculate how genetic and environmental factors can regulate the PD-1/PD-L1 pathway, and discuss PD-1/PD-L1-based therapeutic approaches for pancreatic islet transplantation and T1D treatment.

Combined Application of Nivolumab and Intravesical Bacillus Calmette-Guérin Led to Acute-Onset Type 1 Diabetes

We report a case of acute-onset type 1 diabetes due to combined application of nivolumab and intravesical Bacillus Calmette-Guérin (BCG). An 84-year-old woman underwent lung resection for pulmonary squamous cell carcinoma. She had been treated for type 2 diabetes and later experienced lung cancer recurrence. She was started on nivolumab treatment, and complete response was achieved for one year. However, during this time, she was diagnosed with superficial bladder cancer and underwent surgery but experienced recurrence. After one month of intravesical BCG instillation, the patient developed acute-onset type 1 diabetes. Thus, we recommend that combined application of nivolumab and intravesical BCG be avoided.

B cell depletion or absence does not impede anti-tumor activity of PD-1 inhibitors

Background

PD-1 inhibitors are approved for multiple malignancies and function by stimulating T cells. However, the role of B cells in the anti-tumor activity of these drugs is unknown, as is their activity in patients who have received B cell depleting drugs or with immunoglobulin deficiencies.

Methods

We studied B cell content in 40 melanomas from patients treated with pembrolizumab or nivolumab and assessed the association with response to therapy. Murine MC38 colon cancer and YUMMER1.7 melanoma models were used to determine whether concomitant anti-CD20 antibody injections diminish the anti-tumor effects of anti-PD-1. Results were validated in muMT mice, which lack B cells.

Results

B cells were sparse in most melanomas and B cell content was not associated with response to anti-PD-1 or overall survival. Employing MC38 and YUMMER1.7 models, we demonstrated that anti-CD20 antibodies reduce tumor-infiltrating B cells yet had no effect on tumor growth, response to PD-1 inhibition, or survival. In muMT mice, T-cell dependent tumor rejection and anti-PD-1 responses were no different than in wildtype C57BL/6 J mice.

Conclusions

The degree of tumor infiltrating B cell content is not associated with response to anti-PD-1 inhibitors in melanoma. PD-1 inhibitors cause tumor shrinkage in murine cancer models even when B cells are absent or are depleted. PD-1 inhibitors are likely to be active in patients with impaired B cell function, such as patients undergoing B cell depletion with drugs including rituximab for conditions such as B cell malignancies or autoimmune disorders.

Electronic supplementary material

The online version of this article (10.1186/s40425-019-0613-1) contains supplementary material, which is available to authorized users.