How to boost my immune system?

Hello,
I just received my blood work showing that neutrophils are slightly down, the same as lymphocites and platelets, while my creatinine is going up a bit. I was wondering about a good booster.
BTW, I'm juicing lots of veggies. is there any particular combination that may be not beneficial?

I also wanted to share what happened earlier today:

I just discovered mold around all the windows of my apartment. Given that I have liver tumours and lung metatasis, I can not expose myself. Hence, I have to move out asap.
Because I need to justify to the landlord my immediate move due to a medical reason, I called my oncologist asking if he could provide me with a letter saying that given my medical condition, exposure to mold spores is hazardous. He said he couldn't make it and that this exposure is not dangerous. That there is no risk at all. (I couldn't belive his saying that). ... I hold my breath...

Then, when I asked if he - as my oncologist - wouldn't prefer me not to be exposed to this hazard, he replied saying that I would have to prove him that mold is toxic. Just like that. I said ok, I'll call you later.

Honestly, I don't understand his position. What is he losing? Even my landlord knows that stuff is toxic! (it feels like when they said months ago that I didn't need to change my diet at all !!?)