Methods for treating a patient using therapeutic immune system neuromodulation and associated devices, systems, and methods are disclosed herein. One aspect of the present technology is directed to methods including modulating nerves proximate a vessel or duct of an immune system organ using an intravascularly or intraluminally positioned therapeutic element. One or more measurable physiological parameters corresponding to an immune system disorder, a condition associated with sympathetic activity in an immune system organ, or a condition associated with central sympathetic activity in the patient can thereby be reduced.
