New approach to generating of human monoclonal antibodies specific to the proteolytic domain of botulinum neurotoxin A.

Introduction: Botulinum neurotoxins (BoNTs) cause botulism and are the most potent natural toxins known. Immunotherapy with neutralizing monoclonal antibodies (MAbs) is considered to be the most effective immediate response to BoNT exposure. Hybridoma technology remains the preferred method for producing MAbs with naturally paired immunoglobulin genes and with preserved innate functions of immune cells. The affinity-matured human antibody repertoire may be ideal as a source for antibody therapeutics against BoNTs. In an effort to develop novel BoNT type A (BoNT/A) immunotherapeutics, sorted by flow cytometry plasmablasts and activated memory B cells from a donor repeatedly injected with BoNT/A for aesthetic botulinum therapy could be used due to obtain hybridomas producing native antibodies. Methods: Plasmablasts and activated memory B-cells were isolated from whole blood collected 7 days after BoNT/A injection and sorted by flow cytometry. The sorted cells were then electrofused with the K6H6/B5 cell line, resulting in a producer of native human monoclonal antibodies (huMAbs). The 3 antibodies obtained were then purified by affinity chromatography, analyzed for binding by Western blot assay and neutralization by FRET assay. Results: We have succeeded in creating 3 hybridomas that secrete huMAbs specific to native BoNT/A and the proteolytic domain (LC) of BoNT/A. The 1B9 antibody also directly inhibited BoNT/A catalytic activity in vitro. Conclusion: The use activated plasmablasts and memory B-cells isolated at the peak of the immune response (at day 7 of immunogenesis) that have not yet completed the terminal stage of differentiation but have undergone somatic hypermutation for hybridization allows us to obtain specific huMAbs even when the immune response of the donor is weak (with low levels of specific antibodies and specific B-cells in blood). A BoNT/A LC-specific antibody is capable of effectively inhibiting BoNT/A by mechanisms not previously associated with antibodies that neutralize BoNT. Antibodies specific to BoNT LC can be valuable components of a mixture of antibodies against BoNT exposure.

The analgesic effects of botulinum neurotoxin by modulating pain-related receptors; A literature review.

Botulinum neurotoxins (BoNTs), produced by Clostridium botulinum, have been used for the treatment of various central and peripheral neurological conditions. Recent studies have suggested that BoNTs may also have a beneficial effect on pain conditions. It has been hypothesized that one of the mechanisms underlying BoNTs' analgesic effects is the inhibition of pain-related receptors' transmission to the neuronal cell membrane. BoNT application disrupts the integration of synaptic vesicles with the cellular membrane, which is responsible for transporting various receptors, including pain receptors such as TRP channels, calcium channels, sodium channels, purinergic receptors, neurokinin-1 receptors, and glutamate receptors. BoNT also modulates the opioidergic system and the GABAergic system, both of which are involved in the pain process. Understanding the cellular and molecular mechanisms underlying these effects can provide valuable insights for the development of novel therapeutic approaches for pain management. This review aims to summarize the experimental evidence of the analgesic functions of BoNTs and discuss the cellular and molecular mechanisms by which they can act on pain conditions by inhibiting the transmission of pain-related receptors.

Tirbanibulin (KX2-391) analog KX2-361 inhibits botulinum neurotoxin serotype A mediated SNAP-25 cleavage in pre- and post-intoxication models in cells.

Botulinum neurotoxins (BoNT) inhibit neuroexocytosis, leading to the potentially lethal disease botulism. BoNT serotype A is responsible for most human botulism cases, and there are no approved therapeutics to treat already intoxicated patients. A growing body of research has demonstrated that BoNT/A can escape into the central nervous system, and therefore, identification of BoNT/A inhibitors that can penetrate BBB and neutralize the toxin within intoxicated neurons would be important. We previously identified an FDA-approved, orally bioavailable compound, KX2-391 (Tirbanibulin) that inhibits BoNT/A in motor neuron assays. Recently, a structural analog of KX2-391, KX2-361, has been shown to exhibit good oral bioavailability and cross BBB with high efficiency in mouse experiments. Therefore, in this work, we evaluated the inhibitory effects of KX2-361 against BoNT/A. Toward this goal, we first evaluated the compound for its effects on cell viability in PC12 cells, via MTT assay, and in mouse embryonic stem cell (mESC)-derived motor neurons, with imaging-based assays. Following, we tested KX2-361 in mESC-derived motor neurons intoxicated with BoNT/A holotoxin, and the compound exhibited activity against the toxin in both pre- and post-intoxication conditions. Excitingly, KX2-361 also inhibited BoNT/A enzymatic component (light chain; LC) in PC12 cells transfected with BoNT/A LC. Furthermore, our molecular docking analyses suggested that KX2-361 can directly bind to BoNT/A LC. Medicinal chemistry approaches to develop structural analogs of KX2-361 to increase its efficacy against BoNT/A may provide a critical lead compound with BBB penetration capacity for drug development efforts against BoNT/A intoxication.

Anatomical considerations of medial eye wrinkles: Guidelines for botulinum neurotoxin injections.

Crow's feet lines in the lateral canthal region are a common concern among aging patients, initially appearing as dynamic wrinkles during facial expressions and becoming more pronounced with age. Botulinum neurotoxin temporarily paralyzes muscles by inhibiting acetylcholine release, smoothing wrinkles and enhancing skin's youthful appearance. Effective treatment requires tailored approaches considering individual anatomy and muscle activity. Recent cadaveric studies identified the tear trough muscle, emphasizing its role in infraorbital support and aging. Clinically, patients often present medial eye wrinkles after BoNT treatment for crow's feet, prompting exploration of underlying mechanisms and management strategies. Three cases demonstrated that medial BoNT injections in the orbicularis oculi muscle significantly improve medial eye wrinkles and tear trough appearance. The study underscores the importance of understanding muscle hyperactivity and anatomical variations for precise treatment. Enhanced injection techniques targeting specific areas can achieve better outcomes and minimize complications, particularly in culturally sensitive regions where facial expressions are valued. This research highlights the necessity for comprehensive anatomical knowledge and patient-specific treatment strategies to address medial eye wrinkles effectively.

Foodborne Botulism Type F: A Rare Presentation of Neurologic Manifestation and Successful Management.

Botulism is a neuroparalytic syndrome resulting from the systemic effects of an exoneurotoxin produced by gram-positive, rod-shaped, spore-forming, obligate anaerobic bacterium Clostridium botulinum. Here, we present the case of a 40-year-old male, presenting with a sudden onset of abdominal pain associated with vomiting. He was admitted for conservative management once the CT of the abdomen and pelvis revealed partial small bowel obstruction with no signs of bowel perforation or ischemia. However, the next day, the patient had a cardiac arrest thought to be secondary to respiratory arrest. The return of spontaneous circulation was achieved after two cycles of cardiopulmonary resuscitation. The patient developed quadriplegia, areflexia, and bilateral ophthalmoplegia. He was empirically treated with pyridostigmine, intravenous immunoglobulin (IVIG), and botulinum antitoxin. Stool polymerase chain reaction (PCR) testing resulted positive for C. botulinum toxin type F. The patient ultimately recovered with botulinum antitoxin and a month of physical and speech therapy. Our case highlights that clinicians should consider botulism as a differential and emphasize the importance of early diagnosis for effective management and prognosis.

Therapy with botulinum neurotoxin for Parkinson's disease.

Botulinum neurotoxin (BoNT) has been in use since the 1970's. Its effect is reached mainly by inhibiting the release of acetylcholine in the synaptic gap of motor neurons or at the motor end plate and the parasympathetic ganglia. In the case of Parkinson's disease, it is used to treat several motor and non-motor symptoms. Within recent years increasingly numerous possible fields of application of BoNT have been found for the treatment of Parkinson's disease, and for some specific symptoms it has in fact become the therapy of choice, while for others it is but one of the therapeutic options that come into consideration when others are not sufficiently effective. In the following, we intend to outline the indications, the possible side effects and also the approvals for therapies with botulinum toxin in the primary and secondary symptoms of Parkinson's disease.

Long-Term Adherence to Onabotulinum Toxin-A Intradetrusor Injections for Neurogenic Dysfunction in Children-A Retrospective Single-Center Evaluation.

Onabotulinum Toxin-A (BTX-A) is a second-line treatment for neurogenic bladder (NB). It requires repeated injections over time, which is a possible limit for long-term adherence, especially in children, as general anesthesia is required. Almost 50% of adults discontinue therapy; few data on pediatric patients are present. The aim of this study is to share our long-term experience of BTX-A adherence in children. This study is a retrospective review of 230 refractory NB patients treated with BTX-A. The inclusion criteria were ≥3 treatments and the first injection performed ≥10 years before the study endpoint. Fifty-four patients were included. Mean follow-up was 10.2 years; mean treatment number was 6.4 for each patient. During follow-up, 7% did not need BTX-A anymore; 76% discontinued therapy, with a prevalence of acquired NB (64% acquired vs. 34% congenital; p = 0.03); sex-based and urodynamic findings did not influence the discontinuation rate (p = 0.6, p = 0.2, respectively). Considering those who withdrew from the therapy, 43% were lost to follow-up/died after a mean of 7.5 years (although 33% still experienced clinical efficacy); 33% changed therapy after a mean of 5.8 years (with reduced efficacy in 22%, persistent efficacy in 11%). BTX-A is a safe and effective therapy for pediatric patients. The treatment abandonment rate is higher for children than for adults; no specific reasons were highlighted. It is necessary to evaluate any age-specific factors to explain these data.

A consensus recombinant elapid long-chain α-neurotoxin and how protein folding matters for antibody recognition and neutralization of elapid venoms.

Antivenoms are essential in the treatment of the neurotoxicity caused by elapid snakebites. However, there are elapid neurotoxins, e.g., long-chain α-neurotoxins (also known as long-chain three-finger toxins) that are barely neutralized by commercial elapid antivenoms; so, recombinant elapid neurotoxins could be an alternative or complements for improving antibody production against the lethal long-chain α-neurotoxins from elapid venoms. This work communicates the expression of a recombinant long-chain α-neurotoxin, named HisrLcNTx or rLcNTx, which based on the most lethal long-chain α-neurotoxins reported, was constructed de novo. The gene of rLcNTx was synthesized and introduced into the expression vector pQE30, which contains a proteolytic cleavage region for exscinding the mature protein, and His residues in tandem for affinity purification. The cloned pQE30/rLcNTx was transfected into Escherichia coli Origami cells to express rLcNTx. After expression, it was found in inclusion bodies, and folded in multiple Cys-Cys structural isoforms. To observe the capability of those isoforms to generate antibodies against native long-chain α-neurotoxins, groups of rabbits were immunized with different cocktails of Cys-Cys rLcNTx isoforms. In vitro, and in vivo analyses revealed that rabbit antibodies raised against different rLcNTx Cys-Cys isoforms were able to recognize pure native long-chain α-neurotoxins and their elapid venoms, but they were unable to neutralize bungarotoxin, a classical long-chain α-neurotoxin, and other elapid venoms. The rLcNTx Cys-Cys isoform 2 was the immunogen that produced the best neutralizing antibodies in rabbits. Yet to neutralize the elapid venoms from the black mamba Dendroaspis polylepis, and the coral shield cobra Aspidelaps lubricus, it was required to use two types of antibodies, the ones produced using rLcNTx Cys-Cys isoform 2 and antibodies produced using short-chain α-neurotoxins. Expression of recombinant elapid neurotoxins as immunogens could be an alternative to improve elapid antivenoms; nevertheless, recombinant elapid neurotoxins must be well-folded to be used as immunogens for obtaining neutralizing antibodies.

A sensitive cell-based assay for testing potency of Botulinum neurotoxin type A.

Botulinum neurotoxin type A (BoNT/A) is a widely used biopharmaceutic for the treatment of neurological diseases and aesthetic medicine, allowing months-long paralysis of target muscles and glands. Large numbers of mice are used for multiple botulinum applications including batch release potency testing, antitoxin testing, countermeasure development and basic research. The mouse bioassay (MBA) has historically been the industry gold-standard in the botulinum field and is still heavily used for commercial product testing. BoNT/A intoxication causes severe suffering and application-specific, non-animal alternatives are urgently needed. It is widely accepted, that a cell-based assay (CBA) is the only way to faithfully replicate all the physiological steps of botulinum intoxication; comprising neuronal binding, internalization, endosomal escape, and cleavage of synaptosomal-associated protein of 25 kDa (SNAP25). However, it has not been straightforward to develop these assays and there are only a limited number of CBA currently in use. This is in part, due to the fact that very few cell lines have the appropriate levels of sensitivity to BoNT/A. In this study we have identified that LAN5 cells, a human neuroblastoma derived cell line, are sensitive to BoNT/A and can be engineered to express a recombinant NanoLuc luciferase tagged SNAP25 reporter molecule. On intoxication, the reporter molecule is cleaved and releases a NanoLuc-SNAP25 fragment which can be specifically captured on a 96-well plate for quantitative luminometry. Importantly, we demonstrate this new cell-based assay exhibits sensitivity comparable to the MBA.

Botulinum neurotoxin type A (BoNT/A) is extensively used in the treatment of neurological disorders and aesthetics. When the toxin enters cells, it targets a protein called SNAP25 and inhibits neurotransmitter release. Traditionally, the potency and safety of BoNT/A has been tested using the mouse bioassay, which causes significant distress to the animals being used. Our study introduces a new method for detecting BoNT/A activity based on LAN5 cells, which are a self-replicating, neuroblastoma-derived human cell line. We have engineered the cells to express a version of SNAP25 that allows the potency of BoNT/A to be measured using a luminescence assay. This new cell-based assay is as sensitive as the mouse bioassay and can be used for commercial product testing. This development could lead to fewer animals being used in research and commercial testing of BoNT/A, benefiting both scientific progress and animal welfare.

Clinical findings and outcome in feline tetanus: a multicentric retrospective study of 27 cases and review of the literature.

Tetanus is a toxigenic illness caused by the action of Clostridium tetani neurotoxin (TeNT), which results in partial or generalized muscle stiffness in infected mammals and birds. The disease is rarely reported in cats due to their innate resistance to the toxin. This multicentric retrospective study aimed to describe a significant population of cats with a diagnosis of tetanus and report their signalment, clinical and neurological signs, diagnostic findings, treatment, and outcome. A retrospective search through medical records from 11 referral centers in Europe resulted in the identification of 27 cases of feline tetanus from July 2005 to April 2023. These cases were further compared with previously reported cases in the veterinary literature. Young cats were more commonly represented than older cats, with a median age of 4 years. Clinical signs were initially characterized by a lame and/or stiff limb, near the primary injury site, in 17/26 (65%) cats. Signs were focal or multifocal in 21/27 (78%) cats of this study and one typical sign was the inability to flex the most severely affected limbs. Electrodiagnostic studies revealed characteristic changes, such as continuous spontaneous motor unit discharges in both agonist and antagonist muscles. Such studies are particularly useful in focal and multifocal cases and should be performed to further support the diagnosis. The toxin was successfully identified in one case using the mouse bioassay. Treatment included antibiotherapy (metronidazole) in most cases, muscle relaxants, appropriate nursing cares and handling of potential complications. Overall, the outcome appeared to be positive, with only 1/27 (3.7%) cats being euthanized due to financial restrains. 23/25 (92%) cats returned to an independent ambulatory capacity on all limbs within a median delay of 25 days. Mild to moderate long-term sequelae were reported in eight (30%) cats. This multicentric study is the first to bring together such a large number of cats affected with tetanus. Presentation of the disease in cats differs from that observed in humans and dogs, with most cats being locally affected. Compared to previous reports of tetanus, this series of cats had a better outcome overall, especially for cats affected with generalized tetanus.

Advances in animal models of Parkinson's disease.

Parkinson's disease is a complex neurodegenerative disease characterized by progressive movement impairments. Predominant symptoms encompass resting tremor, bradykinesia, limb rigidity, and postural instability. In addition, it also includes a series of non-motor symptoms such as sleep disorders, hyposmia, gastrointestinal dysfunction, autonomic dysfunction and cognitive impairment. Pathologically, the disease manifests through dopaminergic neuronal loss and the presence of Lewy bodies. At present, no significant breakthrough has been achieved in clinical Parkinson's disease treatment. Exploring treatment modalities necessitate the establishment of scientifically sound animal models. In recent years, researchers have focused on replicating the symptoms of human Parkinson's disease, resulting in the establishment of various experimental animal models primarily through drugs and transgenic methods to mimic relevant pathologies and identify more effective treatments. This review examines traditional neurotoxin and transgenic animal models as well as α-synuclein pre-formed fibrils models, non-human primate models and non-mammalian specie models. Additionally, it introduces emerging models, including models based on optogenetics, induced pluripotent stem cells, and gene editing, aiming to provide a reference for the utilization of experimental animal models and clinical research for researchers in this field.

Model-based interspecies interpretation of botulinum neurotoxin type A on muscle-contraction inhibition.

Botulinum neurotoxins (BoNTs) are commonly used in therapeutic and cosmetic applications. One such neurotoxin, BoNT type A (BoNT/A), has been studied widely for its effects on muscle function and contraction. Despite the importance of BoNT/A products, determining the blood concentrations of these toxins can be challenging. To address this, researchers have focused on pharmacodynamic (PD) markers, including compound muscle action potential (CMAP) and digit abduction scoring (DAS). In this study, we aimed to develop a probabilistic kinetic-pharmacodynamic (K-PD) model to interpret CMAP and DAS data obtained from mice and rats during the development of BoNT/A products. The researchers also wanted to gain a better understanding of how the estimated parameters from the model relate to the bridging of animal models to human responses. We used female Institute of Cancer Research mice and Sprague-Dawley (SD) rats to measure CMAP and DAS levels over 32 weeks after administering BoNT/A. We developed a muscle-contraction inhibition model using a virtual pharmacokinetic (PK) compartment combined with an indirect response model and performed model diagnostics using goodness-of-fit analysis, visual predictive checks (VPC), and bootstrap analysis. The CMAP and DAS profiles were dose-dependent, with recovery times varying depending on the administered dose. The final K-PD model effectively characterized the data and provided insights into species-specific differences in the PK and PD parameters. Overall, this study demonstrated the utility of PK-PD modeling in understanding the effects of BoNT/A and provides a foundation for future research on other BoNT/A products.

Surgical management of chronic sixth cranial nerve palsy: case report and literature review.

Background: Esotropia resulting from sixth cranial nerve palsy can substantially impact an individual's visual acuity and overall quality of life. If the condition does not resolve in 6-10 months, surgical intervention may be necessary. Various muscle surgeries may be considered, with vertical rectus muscle transposition emerging as the primary option for treatment of complete palsy. However, this technique carries the risk of anterior segment ischemia and post-surgery deviations. Herein, we present a successful treatment of chronic complete sixth nerve palsy using a modified Nishida procedure, without splitting or tenotomy, and an adjunct botulinum toxin A (BTA) injection in the ipsilateral medial rectus muscle. Case Presentation: A 59-year-old woman with a history of traumatic sixth nerve palsy had previously undergone horizontal muscle strabismus surgeries. Following multiple left medial rectus recessions, lateral rectus resection, and BTA injections, esotropia persisted. The worsening of her condition led to emotional distress and impaired social interaction. Initial examination revealed marked esotropia and limited left eye abduction. Magnetic resonance imaging (SIGNA MR750w, GE Healthcare, Waukesha, WI, USA) of the left eye revealed a contracted medial rectus muscle and substantial atrophy of the left lateral rectus muscle. A modified Nishida procedure was performed with an injection of 3 units of BTA into the ipsilateral medial rectus muscle, resulting in improved ocular alignment and stable findings after nine postoperative months. Furthermore, we supported our successful outcome with a summary of similar reported cases of sixth nerve palsy managed using the modified Nishida procedure with or without adjunctive procedures. Conclusions: Following the modified Nishida procedure, the patient experienced a reduction in diplopia, improved ocular alignment and stability, and an increased binocular diplopia-free field. This case underscores the importance of an individualized approach to complex strabismus cases and highlights the modified Nishida procedure as a valuable tool in such circumstances. In the future, strabismus management will focus on refining personalized treatment and exploring innovative techniques for complex cases. Our success in using a combination of Nishida procedure and BTA injection should be further investigated in large-scale studies.

Clinical implications of genetic polymorphisms in blepharospasm.

The possible genetic variants associated with blepharospasm (BSP) and facial dystonia have been investigated. Although genetic variants associated with BSP have been extensively studied, the contribution of single-nucleotide polymorphisms towards this condition remains poorly understood. In addition, the etiology of BSP remains to be fully elucidated. Therefore, the present study aimed to assess the role of polymorphisms in the torsin 1A (TOR1A), dopamine receptor D (DRD)2 and DRD5 genes in South Korean patients with BSP. Furthermore, the role of genetic variants of these three aforementioned genes was investigated. A prospective case-control study was established, where 56 patients with BSP and 115 healthy controls were recruited at the Department of Ophthalmology of CHA Bundang Medical Center (Seongnam, South Korea) using single nucleotide polymorphisms analysis by real-time PCR. The TOR1A rs1182CC/DRD5 rs6283TC genotype combination was found to be associated with decreased BSP risk [adjusted odds ratio (AOR), 0.288; P=0.013]. DRD5 rs6283 was observed to be associated with the periocular type of BSP in the co-dominant (for the TC genotype; AOR, 0.370; P=0.029) and dominant models (AOR, 0.406; P=0.029). The recessive model of TOR1A rs1801968 (AOR, 0.245; P=0.030), and the recessive (AOR, 0.245; P=0.029) and over-dominant models (AOR, 2.437; P=0.019) of DRD2 rs1800497 were found to be associated with superior responses to botulinum neurotoxin A (BoNT) treatment. By contrast, dominant (AOR, 0.205; P=0.034) and additive (AOR, 0.227; P=0.030) models of DRD5 rs6283 were associated with poor responses to BoNT treatment. To conclude, these results suggested that DRD2 rs1800497 can confer genetic susceptibility to BSP responses to BoNT treatment, whereas the TOR1A rs1182CC/DRD5 rs6283TC genotype combination appeared to contribute to the association with BoNT efficacy in BSP.

The efficacy of various interventions as good strategies to reduce pain in botulinum neurotoxin A for wrinkles. A systematic review of the randomized controlled trials (RCTs).

Various topical interventions have been described to minimize botulinum neurotoxin-A (BoNT)-induced pain. The purpose of this study is to conduct a systematic review of relevant randomized controlled trials (RCTs) to compare the efficacy of pain relief methods during BoNT injection. PubMed, Scopus, and Web of Science were searched using "Botox," "Botulinum," or "BTX." We identified RCTs in which BoNT were injected to eliminate wrinkles. The pain score was the study outcome, and pain reduction method was compared with routine one. The meta-analysis was reported using the PRISMA checklist. The Higgins I(I2) statistical model assessed results heterogeneity. Two thousand one hundred and twenty-three articles were identified, thirteen articles eligible. Two hundred and sixty-two healthy volunteers were performed on these RCTs. Meta-analysis evaluated different methods to ease BoNT injection pain, and these methods significantly improved outcomes by 0.23% (95%CI, 0.11-0.46, p = .000). Subgroup analysis based on injection area showed no significant heterogeneity, but heterogeneity decreased when subgroup analysis based on other methods was done (Cochran's Q test = 115.52, p = .0001, I2 = 87.9%). This meta-analysis confirms the effectiveness of pain relief methods during BoNT injection. Evaluation of different methods showed their effectiveness, but finding the best method requires comparative studies, although the role of pH and EMLA has been proven.

Ascorbyl palmitate (ASC16) as a potential inhibitor of toxicity induced by Crotalus durissus terrificus venom.

It is well known that C. d. terrificus venom causes pathophysiological effects such as neuropathies, coagulopathies, and even death. Previous studies have reported that ASC16 can interact with monomeric phospholipases A2 from the venom of various snake species (e.g., Vipera russelli and Echis carinatus). As a result, ASC16 has been proposed as an inhibitor of the toxic effects induced by the heterodimeric complex (crotoxin) and other components of the venom of C. d. terrificus. To investigate this further, in silico studies were designed using the crotoxin (CTX) protein complex as a model, and experimental assays were conducted to evaluate the inhibitory effect of ASC16 on CTX, as well as on other venom enzymes such as thrombin-like enzyme (TLE), phosphodiesterase (PDE) and l-aminoxidase (LAAO). For in vitro assays, specific substrates were used, and lethal activity was measured over 48 h using an in vivo murine experimental model (CF01). In silico studies have indicated that the hydrophilic portion of ASC16 adopts a stable conformation while interacting with the catalytic site of crotoxin. At the highest concentrations, ASC16 significantly inhibited the activities of PLA2 (40.89 ± 0.09 %), TLE (11.03 ± 0.69 %), PDE (51.33 ± 2.83 %), and LAAO (56.79 ± 2.91 %). Furthermore, ASC16 neutralized the 2 LD50 lethality of crotalic venom. These findings lay the groundwork for designing promising adjuvants that can facilitate the incorporation of a larger quantity of proteins in immunization schemes. Consequently, this approach aims to achieve higher antibody titers, reduce the number of required immunizations, and minimize local damage in the producer animal.

Navigating the spectrum of pediatric sialorrhea management: A narrative review.

OBJECTIVE: This review summarizes the approaches to pediatric sialorrhea management from least-to-most invasive: non-pharmacological management, anticholinergic medications, botulinum neurotoxin, non-invasive surgery, and invasive surgical intervention. REVIEW METHODS: An electronic literature review identified English-language articles on sialorrhea management in pediatric patients. Publications between 1982 and 2022 were used, with a focus on articles published from 2012 to 2022. Additional augmentation of pharmacologic information was obtained from the latest editions of medical textbooks supplemented with official package inserts of investigated medications. CONCLUSIONS: Sialorrhea is abnormal in patients greater than four years of age. Severe cases warrant intervention to improve patient quality of life and reduce caregiver burden. Management starts with conservative approaches. Viable candidates begin with non-pharmacological management options. Anticholinergic medications can decrease saliva production, but adverse side effects may outweigh benefits. Botulinum neurotoxin injection of the salivary glands decreases salivary flow rate; however, relief is transient and thus multiple treatments are required. Non-invasive sclerotherapy is an emerging treatment option showing promising results for sialorrhea. In contrast, surgical intervention is reserved as a last-resort treatment for patients with severe symptoms, due to its higher risk for adverse consequences. IMPLICATIONS FOR PRACTICE: Physicians should be familiar with the different pediatric sialorrhea management options, including advantages and disadvantages, to adequately facilitate shared decision making with caretakers of pediatric patients who require treatment.

Current use of neurotoxins for alleviating symptoms of cervical dystonia.

INTRODUCTION: Cervical dystonia (CD) causes involuntary movements and postures of the head, neck, and shoulders, as well as nonmotor symptoms including pain, mood, and sleep dysfunction, and impacts quality of life. The first-line treatment for CD is botulinum neurotoxin (BoNT) injections. AREAS COVERED: The clinical presentation and diagnosis of CD, as well as where BoNT resides in the treatment landscape, is reviewed first. Next, the mechanism of action and the pharmacological differences in the available preparations of BoNT products are explained. The evidence base for motor and nonmotor efficacy and safety of the available BoNT formulations is reviewed, with attention to duration of benefit as a driver of patient satisfaction. Practical determinants of BoNT efficacy are reviewed including muscle selection, accurate muscle injection, factors related to poor or deteriorating response, and immunogenicity. EXPERT OPINION: BoNT represents a significant advancement in the treatment of CD. More accurate diagnosis, muscle selection and targeting, and dosing can improve outcomes with existing BoNT formulations. Further refinement of BoNT potency, duration of action, safety, and immunogenicity will help reduce unmet needs in the magnitude and duration of benefit. Additional validation of DBS and MRI-guided focused ultrasound may expand options for patients with toxin nonresponse.

Montelukast treatment response according to eosinophil-derived neurotoxin level in children with allergic rhinitis.

BACKGROUND: Eosinophil-derived neurotoxin (EDN) is an important biomarker of eosinophilic inflammation. METHODS: This study evaluated Montelukast treatment response according to EDN concentration in children with perennial allergic rhinitis (PAR). Fifty-two children with PAR were recruited and took a combination of Montelukast (5mg) and Levocetirizine (5mg) "Mont/Levo Group" or only Montelukast (5mg) "Mont Group" for 4 weeks. All caregivers were instructed to record rhinitis symptoms for 4 weeks. EDN was measured before and after treatment. RESULTS: Daytime nasal symptom scores (DNSS) significantly decreased in both the Mont/Levo (p = 0.0001; n = 20) and Mont Group (p < 0.0001; n = 20), but there were no significant differences between the two groups. EDN concentration also significantly decreased after treatment in both groups (p < 0.0001 and p < 0.001, respectively). For secondary analysis, children with a high initial EDN concentration (EDN ≥ 53 ng/mL) were placed in the "High EDN Group", while those with a lower initial EDN concentration (EDN < 53 ng/mL) were put in the "Low EDN Group". Both groups experienced significant reductions in DNSS after either treatment regimen (p < 0.0001 and p = 0.0027, respectively) but the High EDN Group had greater reductions. EDN concentrations in the High EDN Group decreased significantly from either treatment (p < 0.0001). CONCLUSION: We found that children with AR and a high serum EDN concentration may respond well to Montelukast treatment. A therapeutic strategy using EDN concentrations in patients with AR to evaluate therapeutic response may help improve quality of care.