Abstract The chopped-lung technique with the use of human and monkey tissues for passive sensitization with human sera of subjects allergic to ragweed has been elaborated. The passive sensitization of the lung tissue could be demonstrated by means of histamine release. The chopped-lung technique was compared with two other techniques of tissue passive sensitization: the Schultz-Dale (S-D) test with monkey ileum and the Prausnitz-Küstner (P-K) test with human skin. It was demonstrated that most probably the same antibody participated in the passive sensitization of chopped monkey or human lungs, monkey ileum, and human skin. This antibody was heat labile. An evaluation was made of the tissue passive-sensitization techniques for the detection of reaginic antibodies. The S-D test is the most sensitive among the discussed techniques. The chopped-lung technique has a good reproducibility but is less sensitive. The classical P-K test is still the simplest method for measuring reagin but, theoretically, may be potentially harmful to the recipient.