Remarks on Passive Transfer

In conclusion, although it is often difficult to distinguish macroscopically between the reactions due to the different eczematogens, this distinction becomes easier under microscopic examination when one considers the differences in the epidermal lesions (spongiosis, acanthosis, necrosis), the quality of the infiltrate, and the magnitude of this infiltration. 

The histological examination is relatively objective. The slides are retained and permit a repetition of the examination, a comparison, and a discussion of the results. This is why we attach such a great significance to the histological examination. 

In blood smears we can observe differences similar to those seen in the infiltrate. 

In guinea pigs exhibiting an infiltrate which is rich in eosinophils, after a patch test with CA and also often with PA, we can also observe, a blood eosinophilia. This is not seen in guinea pigs sensitized to DNCB. 

there is a correlation between the quantity of tissue eosinophils after the test and that of blood eosinophils. This relationship is significant. 

---