Lectins from Allomyrina dichotoma (ADL) and Bombyx mori (BML) were partially purified by physiological saline extraction, ammonium sulfate fractionation, anion exchange column chromatography on DEAE Sephadex A-50 and gel filtration column chromatography on Sephadex G-200. An assay for cytokine expression was carried out by using reverse transcription polymerase chain reaction(RT-PCR). mRNA isolated from PBMC(human peripheral blood mononuclear cells) were stimulated with ADL(O.D.=0.2) and BML(O.D.=0.1) for various times(1,4,8,24,48 and 72 h) and various cytokine mRNA assessed by RT-PCR were shown as follows: The patterns of bands for IL-1 mRNA of BML were very similar with those from ADL and these bands were decreased along the increasing reaction times after showing a strong band at 1 h. However mRNA expressions for IL-2, IL-6, $IFN{gamma}$ and $TNF{alpha}$ showed different patterns between ADL and BML. With the effect of ADL, the expression of IL-2 and IL-6 mRNA were continuously detected until 72 h with the strongest band of IL-2 mRNA at 24 h. The strong bands of $IFN{gamma}$ mRNA were observed from 4 to 8 h but the strongest one of $TNF{alpha}$ was just observed at 1 h. Meanwhile with BML, the bands for IL-2 and $IFN{gamma}$ were increased along the increasing reaction times until 72 h. The strongest bands were showed from 4 to 8 h with IL-6 and at 8 h with $TNF[alpha}$. To verify quantitatively ELISA was used for assay of protein secretions of the cytokine gene with IL-2 and $IFN{gamma}$ expressed markedly different in RT-PCR. The highest cytokine secretion for IL-2 was demonstrated at 48 h. The production of $IFN{gamma}$ was markedly increased at 24 h and secreted highest at 72 h. These result suggest that ADL and BML, as inducers of cytokines, can elicit detectable cytokine mRNA from PBMC within the first few hours of stimulation and maintain the production of cytokines for a few days by the methods of RT-PCR and ELISA.