Final answer:
The meridians mentioned do not correlate with medically recognized concepts of immunodeficiency disorders within biology. Instead, fat-digesting enzymes are mainly produced by the pancreas, and not by the liver, gallbladder, or small intestine.
Step-by-step explanation:
The question relates to which meridians are most involved in immunodeficiency disorders. However, when reviewing biology and the topics mentioned such as immunodeficiency disorders, HIV AIDS, allergies, autoimmune disease, and cell-mediated response, there is no mention of meridians which are typically associated with traditional Chinese medicine and not scientifically recognized medical concepts.
Instead, I can provide information on the production of most fat-digesting enzymes which are produced by the pancreas. The pancreas secretes digestive enzymes into the duodenum, including lipases that are essential for lipid digestion. The gallbladder stores and concentrates bile from the liver, and this bile is subsequently released into the small intestine to aid in the digestion process, though the enzymes themselves are not produced there.