Neurology and immunology: a tale of two systems
While the respective histories of both neurology and immunology are quite well studied, hardly any attention has hitherto been given to the historical and epistemological relations between the immune system (IS) and the central nervous system (CNS). Both immunology and neurology were established as independent experimental sciences in the same time period, namely ca. 1900. This period, it will be argued, was characterized by an intensive attempt to make sense of seemingly idiosyncratic physiological phenomena in terms of experimentally demonstrable agents and their effects. The definition of synapses and the newly conceived notion of a reflex (notably as employed by Sherrington) enabled the experimentalisation of neurophysiology and the construction of the notion of a "nervous system". At the same time, Emil von Behring, Ilya Metchnikoff and Paul Ehrlich instituted a science of immunity--itself a highly idiosyncratic phenomenon--conceived in terms of specific reactions between the antigen and its corresponding antibodies (and, possibly also specific cells).
The paper will argue that throughout the twentieth century, attempts to reconcile the IS with the CNS stumbled over the inability to reconcile the notion of the reflex with that of a specific immune reaction. Charles Richet's work towards the discovery of anaphylaxis between 1890-1902 will be the first to be discussed. His discovery of this averse immune reaction, for which he was awarded the Nobel prize, is a well known fact. Yet historians have hardly realised that Richet actually arrived at anaphylaxis while attempting to establish a new notion of a "reflex", which he had conceived as a bodily defense mechanism with a neurological underpinning. Some thirty years later, Serge Metalnikov, a disciple of Ilya Metchnikoff, has attempted to reverse this logic, and to make sense of a well established cellular immune response (phagocytosis) in terms of Pavlovian reflexes. Finally, the paper will discuss the recent revival of "neuroimmunology" as exemplified by the work of Robert Ader and Nicholas Cohen in the 1980s, who attempted to integrate conditioning experiments with newly discovered facts about similar binding sites (e.g., for ACTH or TSH) in cells of both the IS and CNS. Characterising all these historical episodes was the failure to translate the notion of a reflex (and its related conceptions, e.g., CS.UCS), into the language of immunological specificity, and vice versa.
Session II -- 19th/20th Century Approaches to the Nervous System
Sixth Annual Meeting of the International Society for the History of the Neurosciences (ISHN) and