Related Clues:

• Cause of an immune response
• It stimulates the immune system
• Immunity trigger
• A or B in blood typing, e.g.
• Zero ___
• Immunity stimulant
• Allowable variation
• Immune response trigger
• Forbearance
• Indulgence
• Open-mindedness
• This is how permissive one might learn to get in the cote
• One might gain ten from such a toxin
• The permitted variation that's not 15 down
• Forbearing, but that's the limit