TG-01(Targovax)

Abstract.  Ear tags containing 40% organophosphate insecticides (diazinon or diazinon plus chlorpyrifos‐ethyl) were applied to control Haematobia irritans (L.) (Diptera: Muscidae) in treated (TG01 and TG02) and untreated (UG01 and UG02) groups of Holstein heifers born in 2001 and 2002, respectively. Control and treated groups were assessed for the abundance of Stomoxys calcitrans (L.) (Diptera: Muscidae) from August 2001 to April 2002 and again from August 2002 to April 2003. The treatment had a high efficacy for control of horn flies (maximum median number per heifer of TG01 and TG02 = 5) but a low effect on the abundance of stable flies. The total numbers of S. calcitrans were 1251 (42.9% of the total) and 1668 (57.1%) for TG01 and UG01, and 1423 (48.8%) and 1494 (51.2%) in TG02 and UG02, respectively. No significant difference in stable fly burden was found in 55 of the 76 weeks evaluated. A unimodal peak of abundance in the spring was found during the first fly season, and a bimodal abundance, with peaks in the spring and autumn, during the second season. No strong associations between horn fly and stable fly burdens was found in individuals of the CG01 (correlation coefficient = 0.13, P > 0.05) or CG02 (correlation coefficient = 0.538, P < 0.05, determination coefficient = 0.289).

Elliptinium acetate (EA) is a new anti‐cancer compound displaying cytostatic activity against various malignancies including hepatoma. Using 3 hepatoma cell lines, we compared the in vitro activity of doxorubicin (reference drug), of EA and of conjugates made up with this latter drug and monoclonal antibodies (MAbs). The linkage was performed by a direct oxidation method. Specific immunoconjugates were prepared with an anti‐alphafetoprotein (AFP) MAb (AF01) or its Fab fragment (Fab AF01). Non‐specific conjugates were obtained with an anti‐thyroglobulin MAb (TG01) or its Fab (Fab TG01). Direct membrane injury (51Cr‐release), DNA and protein synthesis as well as AFP release were investigated for all compounds. Free EA displayed only weak activity on DNA and protein synthesis, at 10‐fold higher molar concentration than doxorubicin. Conjugation of EA with whole AF01 allowed significant potentiation of protein synthesis inhibition without affecting the 3 other tests. In contrast, Fab AF01 × EA conjugates displayed a marked effect in the 4 tests; in particular, this conjugate was at least 100 times more efficient than any other compound when tested in the 51Cr‐release test. Neither Fab AF01 nor free EA alone or in combination exhibited such an effect. Fab TG01 × EA conjugate was not directly cytotoxic but potentiated inhibition of DNA and protein synthesis between 2‐ and 10‐fold. The mechanism of the direct cytotoxic effect of anti‐AFP Fab × EA conjugate, which has never been described in any other immunodrug model, was investigated.