No abstract

SUMMARYTwo methods are described for the extraction of enterotoxin from foods incriminated in incidents of staphylococcal food poisoning. Enterotoxin was detected serologically in 12 of 24 food samples from 20 separate incidents: eight samples contained enterotoxin A, three contained D and one both A and B. The amount of enterotoxin in nine foods, based on 100 % recovery, varied from 0-02 to 0 09 ,tg./g.

Group-specific complement-fixing antigen (GS antigen) was studied by the complement-fixation test in various avian and mammalian tumours, induced with the following strains of avian tumour virus ( A T V ) : Schmidt-Ruppin strain of Rous sarcoma virus ( S R -R S V ) , Prague strain of R S V ( P R -R S V ) , Fujinami sarcoma virus ( F S V ) and Bratislava 77 virus (B77V). All primary tumours induced in chicks by S R -R S V , FSV and B77V, as well as all duck tumours induced with B77V, contained high titres of GS antigen when studied with high-titre rabbit antiserum against purified GS antigen of avian myeloblastosis virus ( A M V ) . In three out of six B77V-induced rat tumours (two virus-producing and one non-virogenic) high titres of GS antigen were detected when examined with rabbit antiserum and with some rat sera obtained from tumour-bearing animals. In three remaining B77V-induced virogenic rat tumours (C21, C22 and C23), GS antigen was not detected with rabbit antiserum; however, sera obtained from these three tumourbearing rats contained high titres of GS antibodies when tested with different GS antigens. Positive results were obtained also with PR-RSV-induced virogenic rat tumour X C . However, all attempts to detect GS antigen in one S R -R S V induced virogenic rat tumour ( M R I ) gave negative results. Possible heterogeneity of A TV-induced GSantigen in mammalian tumours is discussed.