The immunculus is considered as the system (general network) of constitutively expressed natural autoantibodies against different extracellular, membrane, cytoplasmic, and nuclear self-antigens (ubiquitous and organ-specific). It is specially noted that the repertoires of natural autoantibodies are surprisingly constant in healthy persons, independent of gender and age, and characterized by only minimal individual peculiarities (individual immune fingerprints). On the other hand, abnormal metabolic changes which precede the clinical manifestation of different diseases showed easily detected changes, rather quantitative than qualitative, in the systems of natural autoantibodies in patients' sera (immunculus distortions). This phenomena could supposedly be used for “mapping” the state of physiological norm in terms of the millions of natural autoantibody repertoires, and for elaboration of the methods for early (preclinical) detection of potentially pathogenic metabolic changes. Could the individual features of the general network of constitutively expressed natural autoantibodies reflect the functional state of the body and be used for “mapping” of normal and pathological functional state? Could the changes in production of some biologically active natural autoantibodies not only reflect the state of the body, but be used for partial compensation of functional deficiency of certain molecular systems? These and related questions are discussed in this article. The research project “immunculus” is proposed for international cooperative investigations.