[Migration of polynuclear neutrophils in vivo. Standardization of the technic]. / Contribution à l'étude de la migration des polynucléaires neutrophiles in vivo. Standardisation de la technique.

The migration of neutrophils across a skin barrier is a commonly employed method for the study of the inflammatory response. This report aims at comparing the leukocyte migration in the presence of two different chemoattractants : autologous serum and pool of serum. The reproducibility of this method has proved to be increasing by using duplicate skin chambers in 30 healty volunteers. The neutrophil migration with the pool of serum appears more homogeneous than with autologous serum. These results permit to obtain a standard curve of the neutrophil migration using a pool of serum.

A method using [3H]leucine-labeled granulocytes or macrophages for migration inhibition assay.

The migration inhibitory activity of supernatants of Con A-Sepharose stimulated MNC cultures was tested by measuring the migration of [3H]leucine-labeled granulocytes or macrophages from agarose-containing capillary tube fragments. The migrated cells were harvested with an automated cell harvester on glass fiber filters and counted in a beta counter. Suspension of the target cells in agarose improves the accuracy of the method since migration from packed capillary tube fragments is sometimes not significantly different as between control and assay preparations. The concentration of agarose may inversely influence results, lower concentrations correlating with higher migration inhibition in the presence of assay supernatants. Different migration inhibition results are obtained when allogeneic granulocytes are used in parallel. For this reason a 10 times concentrated supernatant from a Con A-Sepharose-stimulated MNC culture, exhibiting the highest LIF activity at any mitogen concentration, was used as standard considered arbitrarily to contain 100 U. On the parallel regression lines of the dilution curves of the standard and assay preparations, reference with the standard is made at 25% migration inhibition as the comparison point.

Experimental investigations in guinea pigs on the recognition of the allergic eczematous reaction: A comparison of the macrophage migration inhibition test with the patch test.

1. The patch test as an in vivo test has disadvantages. It is our impression that biologically false reactions occur in approximately 5%. 2. The MIT as an in vitro test is very time consuming, but safe for the patient. It is supposed to give up to 20% false reactions. 3. In 76 and 72% of 156 guinea pigs sensitized with potassium bichromate and sulfasol respectively, both the test methods gave results in agreement. 4. Sensitization by potassium bichromate estimated by patch test only was 30%, and by MIT only also 30%, but the two test methods disagreed in 24%. 5. Sensitization by sulfasol evaluated in the patch test only was 36%, and in the MIT only 48% but the two test methods disagreed in 28%. 6. The differences between the results of the two test methods are not satistically significant and their failure rate does not provide absolutely sure results, but we believe that the patch test is preferrable in recognition of contact allergy because it is in vivo and probably has a lower failure rate in comparison with the MIT in the human.