Quantitative Iodination of Human Blood Polymorphonuclear Leukocytes

Abstract. It was shown by Pincus and Klebanoff that a correlation existed between leukocytic iodination measured in vivo and microbicidal leukocytic activity. We have analysed the results of this test in relation to time and in the presence of variable quantities of polymorphonuclear leukocytes (PMN). The values observed per time and PMN unit proved to be equivalent in the presence of 2. 5 × 105 PMN or 5. 0 × 105 PMN per 0.5 ml of incubation medium, measured after 10, 20 and 30 minutes or in the presence of 1. 0 × 106 PMN, measured after 10 minutes. That is to say iodination is proportional to leukocyte concentration and incubation time. Increase of either the quantity of cells or the incubation time, beyond the area we defined, reduce iodination per cell and per unit of time. Concerning the patients with an insufficient iodination, we have studied 2 parameters in the presence of 5. 0 × 105 PMN:1) initial iodination measured after 10 and 20 minutes and 2) stability of iodination measured after 60 minutes. These two parameters were equally affected in two cases with myelofibrosis, 3 patients with acquired refractory anaemia, one with chronic lymphoid leukaemia, one with erythroleukaemia, one with hairy cell leukaemia, one with systemic mastocytosis and almost complete myeloperoxidase deficiency, one with sickle cell disease, two with liver diseases and two with chronic myeloid leukaemia. The iodination at the 60th minute was more affected than at the 10th minute with a patient with myelofibrosis and 4 other patients with acquired refractory anaemias. The significance of these differences is not well understood; however the meaning of the decrease in the iodination of whatever type is that a PMN anomaly exists directly related to the myeloperoxidase H2O2 halogenation system, or to one of the stages of engulfment and/or metabolic events preceeding it and leading to the production of H2O2. This test, with the alterations we introduced, is suggested as a test for detection of functional PMN abnormalities.