Do immunoglobulin G and immunoglobulin E anti-l-asparaginase antibodies have distinct implications in children with acute lymphoblastic leukemia? A cross-sectional study

A Review of L-Asparaginase Hypersensitivity in Paediatric Acute Lymphoblastic Leukaemia Patients with Regard to the Measurement of Anti-Asparaginase Antibodies and Their Genetic Predisposition

L-asparaginase is effective as part of the first line childhood acute lymphoblastic leukaemia (ALL) treatment regimen but suffers the risk of antibody production causing immune-mediated sequelae. This article aimed to describe the clinical implication of L-asparaginase hypersensitivity and review the types of antibodies and genetic polymorphisms contributing to it. Clinical or subclinical L-asparaginase hypersensitivity may lead to suboptimum therapeutic effect and jeopardise the clinical outcome in ALL children. Anti-asparaginase antibodies immunoglobulin (Ig)G, IgM and IgE were identified in the L-asparaginase hypersensitivities. Enzyme-linked immunosorbent assay (ELISA) is commonly used to quantify the IgG and IgM levels. The role of IgE in mediating L-asparaginase hypersensitivity is contradictory. Moreover, the presence of antibodies may not necessarily correlate inversely with the L-asparaginase efficacies in some studies. Patients with specific genetic variants have been shown to be more susceptible to clinical hypersensitivity of L-asparaginase. With the advance of technology, gene polymorphisms have been identified among Caucasians using whole-genome or exon sequencing, but the evidence is scanty among Asians. There is lack of pre-clinical study models that could help in understanding the pathophysiological pathway co-relating the gene expression and anti-asparaginase antibody formation. In conclusion, future research studies are required to fill the current gap in understanding the immune mediated reactions towards L-asparaginase upon its administration and its potential impact to the disease outcome.

Allergic Reactions to E. coli Asparaginase are Associated with Decreased Asparaginase Activity in an Indonesian Pediatric Population with ALL

PURPOSE

The asparaginase's (ASP) utility for ALL treatment is limited by neutralizing antibodies, which is problematic in countries whose access limited to alternative preparations. ASP antibody levels and activity was measured during remission induction and associated with allergy manifestations.

METHODS

E. coli ASP was dosed at 7500 IU/m2. ASP IgG antibody levels were quantified at the beginning and end of induction. ASP activity was measured 24 hours after 1st and 5th dose (standard-risk) or 7th dose (high-risk patients) administration, and within 24 hours in case of allergic reactions. Allergy was monitored by CTCAE version 3. Parametric and non-parametric was performed for data analysis.

RESULTS

ASP antibody and activity levels were available in 41/63 consecutive patients. Allergic manifestations occurred in 13/41, with urticaria being the most frequent. There were no significant differences in subject characteristics based on allergic reactions. The 5th dose was the most frequent time of onset. Antibody levels in allergy group at the end of induction did not differ from those at baseline (p<0.05). Using a 24-hour level of 100 mU/mL as a threshold for adequate ASP activity, 6/13 patients with allergy had adequate levels compared to 26/28 patients without (p<0.05). The ASP activity level at the end of induction phase in both groups did not show a significant decrement.

CONCLUSION

The E. coli ASP activity with adequate levels were significantly higher in non-allergy group. Its activity level was not accompanied by increment of IgG in allergic group indicates other factors might affect activity levels in allergy group.

Current state of molecular and metabolic strategies for the improvement of L-asparaginase expression in heterologous systems

Heterologous expression of L-asparaginase (L-ASNase) has become an important area of research due to its clinical and food industry applications. This review provides a comprehensive overview of the molecular and metabolic strategies that can be used to optimize the expression of L-ASNase in heterologous systems. This article describes various approaches that have been employed to increase enzyme production, including the use of molecular tools, strain engineering, and in silico optimization. The review article highlights the critical role that rational design plays in achieving successful heterologous expression and underscores the challenges of large-scale production of L-ASNase, such as inadequate protein folding and the metabolic burden on host cells. Improved gene expression is shown to be achievable through the optimization of codon usage, synthetic promoters, transcription and translation regulation, and host strain improvement, among others. Additionally, this review provides a deep understanding of the enzymatic properties of L-ASNase and how this knowledge has been employed to enhance its properties and production. Finally, future trends in L-ASNase production, including the integration of CRISPR and machine learning tools are discussed. This work serves as a valuable resource for researchers looking to design effective heterologous expression systems for L-ASNase production as well as for enzymes production in general.

Hypersensitivity reactions to asparaginase therapy in acute lymphoblastic leukemia: immunology and clinical consequences

Asparaginase is commonly used in combination therapy of acute lymphoblastic leukemia. However, as an immunogenic protein, hypersensitivity reactions (HSRs) during asparaginase therapy are frequent, indicating the development of anti-asparaginase antibodies. These can be associated with diminished clinical effectiveness, including poorer survival. Therapeutic drug monitoring of serum asparaginase activity to confirm complete asparagine depletion is therefore crucial during asparaginase therapy. Switching to alternative types of asparaginase is recommended for patients experiencing HSRs or silent inactivation; those with HSRs or silent inactivation on Escherichia coli-derived asparaginases should switch to another preparation. However, prior global shortages of Erwinia asparaginase highlight the importance of alternative non-E. coli-derived asparaginase, including recombinant Erwinia asparaginase.

Hypersensitivity reactions to chemotherapy: an EAACI Position Paper

Chemotherapeutic drugs have been widely used in the treatment of cancer disease for about 70 years. The development of new treatments has not hindered their use, and oncologists still prescribe them routinely, alone or in combination with other antineoplastic agents. However, all chemotherapeutic agents can induce hypersensitivity reactions (HSRs), with different incidences depending on the culprit drug. These reactions are the third leading cause of fatal drug-induced anaphylaxis in the United States. In Europe, deaths related to chemotherapy have also been reported. In particular, most reactions are caused by platinum compounds, taxanes, epipodophyllotoxins and asparaginase. Despite their prevalence and relevance, the ideal pathways for diagnosis, treatment and prevention of these reactions are still unclear, and practice remains considerably heterogeneous with vast differences from center to center. Thus, the European Network on Drug Allergy and Drug Allergy Interest Group of the European Academy of Allergy and Clinical Immunology organized a task force to provide data and recommendations regarding the allergological work-up in this field of drug hypersensitivity reactions. This position paper aims to provide consensus on the investigation of HSRs to chemotherapeutic drugs and give practical recommendations for clinicians that treat these patients, such as oncologists, allergologists and internists. Key sections cover risk factors, pathogenesis, symptoms, the role of skin tests, in vitro tests, indications and contraindications of drug provocation tests and desensitization of neoplastic patients with allergic reactions to chemotherapeutic drugs. Statements, recommendations and unmet needs were discussed and proposed at the end of each section.

Identification of L-asparaginases from Streptomyces strains with competitive activity and immunogenic profiles: a bioinformatic approach

The enzyme L-asparaginase from Escherichia coli is a therapeutic enzyme that has been a cornerstone in the clinical treatment of acute lymphoblastic leukemia for the last decades. However, treatment effectiveness is limited by the highly immunogenic nature of the protein and its cross-reactivity towards L-glutamine. In this work, a bioinformatic approach was used to identify, select and computationally characterize L-asparaginases from Streptomyces through sequence-based screening analyses, immunoinformatics, homology modeling, and molecular docking studies. Based on its predicted low immunogenicity and excellent enzymatic activity, we selected a previously uncharacterized L-asparaginase from Streptomyces scabrisporus. Furthermore, two putative asparaginase binding sites were identified and a 3D model is proposed. These promising features allow us to propose L-asparaginase from S. scabrisporus as an alternative for the treatment of acute lymphocytic leukemia.

Hypersensitivity reactions to asparaginase in mice are mediated by anti-asparaginase IgE and IgG and the immunoglobulin receptors FcεRI and FcγRIII

Asparaginase is an important drug for the treatment of leukemias. However, anti-asparaginase antibodies often develop, which can decrease asparaginase drug levels and increase the risk of relapse. The aim of this study is to identify the immunoglobulin isotypes and receptors responsible for asparaginase hypersensitivities. Mice immunized with asparaginase developed anti-asparaginase IgG1 and IgE antibodies, and challenging the sensitized mice with asparaginase induced severe hypersensitivity reactions. Flow cytometry analysis indicated that macrophages/monocytes, neutrophils, and basophils bind asparaginase ex vivo through FcγRIII. In contrast, asparaginase binding to basophils was dependent on FcγRIII and IgE. Consistent with the asparaginase binding data, basophil activation by asparaginase occurred via both IgG/FcγRIII and IgE/FcεRI. Depleting >95% of B cells suppressed IgG but not IgE-dependent hypersensitivity, while depleting CD4⁺ T cells provided complete protection. Combined treatment with either anti-IgE mAb plus a platelet-activating factor receptor antagonist or anti-FcγRIII mAb plus a H1 receptor antagonist suppressed asparaginase hypersensitivity. The observations indicate that asparaginase hypersensitivity is mediated by antigen-specific IgG and/or IgE through the immunoglobulin receptors FcγRIII and FcεRI, respectively. Provided that these results apply to humans, they emphasize the importance of monitoring both IgE- and IgG-mediated asparaginase hypersensitivities in patients receiving this agent.

Marine microbial L-asparaginase: Biochemistry, molecular approaches and applications in tumor therapy and in food industry

The marine environment is a rich source of biological and chemical diversity. It covers more than 70% of the Earth's surface and features a wide diversity of habitats, often displaying extreme conditions, where marine organisms thrive, offering a vast pool for microorganisms and enzymes. Given the dissimilarity between marine and terrestrial habitats, enzymes and microorganisms, either novel or with different and appealing features as compared to terrestrial counterparts, may be identified and isolated. L-asparaginase (E.C. 3.5.1.1), is among the relevant enzymes that can be obtained from marine sources. This amidohydrolase acts on L-asparagine and produce L-aspartate and ammonia, accordingly it has an acknowledged chemotherapeutic application, namely in acute lymphoblastic leukemia. Moreover, L-asparaginase is also of interest in the food industry as it prevents acrylamide formation. Terrestrial organisms have been largely tapped for L-asparaginases, but most failed to comply with criteria for practical applications, whereas marine sources have only been marginally screened. This work provides an overview on the relevant features of this enzyme and the framework for its application, with a clear emphasis on the use of L-asparaginase from marine sources. The review envisages to highlight the unique properties of marine L-asparaginases that could make them good candidates for medical applications and industries, especially in food safety.