Humoral

HUMORAL (from Latin humor—fluid), connected in one way or another with the body fluids (blood, lymph), in contrast to the concept of "cellular," which indicates a connection with the body cells (of cellular origin). Thus, the humoral direction in the doctrine of anaphylaxis tends to connect the mechanism of anaphylactic shock with processes occurring in the blood of sensitized animals upon repeated administration of the antigen (obstruction of vessels on the basis of the formation of more or less coarse or, conversely, fine flocculates depending on the labilization of blood colloids, etc.), whereas cellular theories postulate the development of the corresponding reaction mainly in cellular territories. Similarly, immunity determined by the presence of protective antibodies in body fluids is humoral immunity, while immunity determined by the activity of phagocytes or corresponding changes in tissue colloids (cells) is cellular immunity. The harmonious consistency in the work of various systems of the organism, maintained in the norm by endocrine organs, is also largely carried out by humoral pathways, because the hormones produced by the aforementioned organs in the overwhelming majority of cases pass directly from the site of production into the blood or lymph and thereby reach the various parts of the organism upon which they act. The significance of humoral factors in the processes taking place in the organism, on the one hand, should not be overestimated, but on the other hand, should not be underestimated either. Since the isolation of various kinds of phenomena is usually more conceived in theory than it actually takes place in reality, in particular, purely humoral factors in fact most often merge or are somehow connected with cellular ones. Supporters of the aforementioned cellular theories of anaphylaxis, for example, do not deny that blood colloids also play a certain role in the mechanism of anaphylactic shock (as a kind of "buffer" in relation to cellular colloids). Antibodies circulating in body fluids appear in them during active immunity as a result of the corresponding activity of cellular mechanisms; the same must be said about hormones, etc. The latter, moreover, in a number of cases act not directly on the working organs, but through the vegetative centers of the diencephalon. On the other hand, reducing everything in pathology to the cell, as numerous followers of Virchow were inclined to do, in view of the above would undoubtedly also be one-sided. (For more details on the humoral direction in pathology, see Pathology.)—Humoral theories of immunity—see Immunity.