My main point was that jinku is defined as " x1 is a vaccine/immune-system stimulant protecting x2 against disease x3 introduced by method x4," while "[v]itamin C increases the proliferative responses of T lymphocytes and the production of interferon, and prevents defects in neutrophils (
http://www.nature.com/ejcn/journal/v60/n1/full/1602261a.html#bib12 )" I think that effect qualifies as an immune-system stimulant, and we certainly know that it protects against scurvy. (And if we open the door to Vitamin C, it probably should also apply to anything else whose lack would cause a "disease" whether or not they specifically stimulate the immune system and/or is a vaccine). And yeah, tatygre jinku sounds fine to me for diathelic immunity. Perhaps an antibody can even be called a sevzi se jinku. If I wanted to distinguish between a disease-warding supplement and vaccine? That's an interesting question because vaccines can portect against bacterial diseases, viral diseases, and even non-microorganism toxins. And what of the elusive cancer vaccine(s) still being sought? So, like many interlingual things, the dividing lines between English and lojban aren't the same, so it would be hard (and, I submit, undesirable) to define a single term that encompasses all that the English word encompasses, while at the same time excluding all that the English term excludes. But I would certainly say that terms like virjinku, jumjinku, and vidjinku would exclude supplements while specifying the agents. And more importantly, why would we NEED to exclude supplements, since j3 specifically addresses which disease we are fighting?