This is a feasibility study to determine whether pulsed ultrasound stimulation targeting the splenic nerve or the cervical vagus nerve can elicit an anti-inflammatory immune response in healthy volunteers.

Recent advances have shown that neural pathways are able to regulate immunity and inflammation. The cholinergic anti-inflammatory pathway is a well-characterized neural circuit that consists of the vagus nerve to spleen circuit, which has been stimulated with implantable devices to improve autoimmune conditions such as rheumatoid arthritis.

Recently, the use of pulsed ultrasonic waves to modulate the neuroimmune pathway has gained interest due to its potential in treating inflammatory disorders non-invasively. This study is designed to test the hypothesis that pulsed ultrasound stimulation can be used effectively in human subjects to control pathogenic inflammatory responses. The overall goal of this project is to determine which, if any, ultrasound stimulation protocols are able to restrict the inflammatory response of immune cells collected from healthy subjects post-ultrasound stimulation.

Four different levels of ultrasound intensity ("doses") will be tested in this study to determine the dose(s) capable of producing an anti-inflammatory effect. The doses will be defined in terms of mechanical index and each subject will receive two different doses of ultrasound. In addition, the study will investigate the efficacy of cervical vagus (neck)-targeted ultrasound, given that it may have an effect similar to spleen-targeted ultrasound through upstream vagus nerve modulation.

Inclusion Criteria:

• Male or female, aged 25-50 years
• Provision of signed and dated informed consent form
• Able to comprehend the study goals and procedures, stated willingness to comply with all study procedures, and availability for the duration of the study
• Considered English proficient so that the subject can follow verbal commands during the ultrasound procedure
• In good general health, as evidenced by medical history
• Laboratory results indicating normal blood count and adequate organ function
• Agreement to adhere to Lifestyle Considerations throughout study duration.

Exclusion Criteria:

• Chronic medical conditions, including cancer (in remission or active cancer), cerebrovascular disease, chronic kidney disease, heart conditions (such as heart failure, coronary artery disease, cardiomyopathies), lung disease, liver disease, hypertension, diabetes mellitus type 1 and 2, human immunodeficiency virus infection, primary immunodeficiencies, solid organ or hematopoietic cell transplantation, tuberculosis, and cystic fibrosis, autoimmune disorders (e.g., rheumatoid arthritis, inflammatory bowel disease), sickle cell anemia or other anemia syndromes
• Mean systolic and diastolic blood pressure values during screening of ≥160 and ≥100 mm Hg, respectively, hypertension on non-selective beta-blockers and/or alpha-methyl dopa, or hypertension requiring more than two anti-hypertension medications
• Obesity (body mass index ≥30 kg/m2)
• Use of anti-inflammatory or immunomodulatory medication, such as non- steroidal anti-inflammatory drugs (NSAIDs), corticosteroids, or other immunosuppressants, within one week of receiving ultrasound delivery
• Use of anticoagulant drugs (e.g., coumadin, direct oral anticoagulants) or antiplatelet drugs (e.g., aspirin, clopidogrel) within one week of receiving ultrasound delivery
• Pregnancy, breastfeeding, or planning to become pregnant during the study
• Active bacterial or viral infection; febrile illness within 2 weeks of receiving ultrasound delivery
• Known allergic reactions to ultrasound gel
• Treatment with another investigational drug or other intervention within 1 month of receiving ultrasound delivery
• Any vaccination received within 1 month of receiving ultrasound delivery
• Current smoker or nicotine use within 2 weeks of receiving ultrasound delivery
• Use of recreational drugs within 2 weeks of receiving ultrasound delivery
• History of arrythmia (e.g., clinically significant bradycardia, atrial flutter, atrial fibrillation, ventricular arrythmias)
• History of deep vein thrombosis or pulmonary embolism
• History of bleeding disorder
• History of seizure
• History of unilateral or bilateral vagotomy
• Participants with an implantable medical device, such as pacemaker, hearing aid implant, or any implanted electronic device
• Surgery or traumatic injury (e.g., visceral injury, cerebral injury) in the past 3 months
• Prior surgery on thyroid or parathyroid glands, esophagus, stomach, or spleen
• Participant is considered by the Investigator, after reviewing medical and psychiatric history, physical examination, and laboratory evaluations, to be unsuitable for any other reason that may either place the patient at increased risk during participation or interfere with the interpretation of the study. outcomes.

Currently, there are no plans to make individual participant data available.