The influence of temperature on phagocytosis
Recent work has shown that the phagocytosis of micro-organisms is a complex phenomenon, involving at least two factors, viz.: (1) the sensitisation of the micro-organism by the opsonin of the blood serum, and (2) the phagocytic act of the polymorphonuclear leucocyte. The latter function has been known for many years to be markedly influenced by temperature. It appeared desirable, however, to ascertain whether, by the modern quantitative methods employed in opsonic work, some definite relationship could be found to subsist between degree of temparature and degree of phagocytosis. In the first set of experiments no attempt was made to separate the respectively functions of sensitisation, and amœboid activity of the leucocyte. Both actions were allowed to proceed simultaneously. Consequently, in Series 1 the leucocytes were put in contact with fresh serum and micro-organisms (staphylococci), and incubated together at different temperatures for the same period of time. Thereafter the number of cocci taken up per leucocyte was calculated on stained films in the usual way. The Staphylococcus aureus employed was an old laboratory strain.