Abstract
Through this series of experiments (Intradermal reactions, HA test, Immunoglobulin test, and Okabe's urine precipitin test), the last one (Okabe's method of the urine precipitin test) has been found to be the most excellent and the most practicable in many respects for the immunological diagnosis of parasitologic diseases such as filariasis. Concerning the experimental materials, most of them are easily obtained in a short period of time except for the anti-D. immitis rabbit serum, and it has been found that the experimental results of these reactions can be kept to some extent for a rather long time without using any preservatives. The details of the chemical and biochemical nature of the antigenic substance are yet unknown, so further investigation of it is surely needed.
