(10 billion (1e9) / 3e11 ~= 3%, for those like me who don't have powers of 10 memorized.) Does that imply that there's a good chance someone's immune system wi

(10 billion (1e9) / 3e11 ~= 3%, for those like me who don't have powers of 10 memorized.) Does that imply that there's a good chance someone's immune system will just fail to generate any appropriate antibodies against a novel intruder? Or does the "fuzzy matching" aspect mean that exploring a small percentage of the space mean you're very likely to get at least some degree of success?