TABLE 2.

Effect of homologous and heterologous antisera on YbST- and YST I-induced fluid accumulation in infant mice

Treated preparationsa	Fluid accumulation ratio after treatment withb:
	TSB/YE	Anti-YST I antiserumc	Anti-YbST antiserumd	Normal rabbit serum	Normal mouse serum
YbST	0.130 ± 0.01	0.129 ± 0.01	0.048 ± 0.02	NDe	0.110 ± 0.01
YST I	0.087 ± 0.02	0.049 ± 0.02	0.087 ± 0.02	0.082 ± 0.01	ND
TSB/YE	0.047 ± 0.01	0.047 ± 0.02	0.048 ± 0.01	ND	0.048 ± 0.01

^aAliquots (600 μl) of YbST- and YST I-containing CSF were incubated (1 h; 37°C) with an equal volume of undiluted homologous and heterologous antisera, TSB/YE, and normal sera prior to assaying in infant mice. 

^bAll fluid accumulation ratios are means (minimum of six animals) ± standard deviations. 

^cA gift from Donald Robertson, University of Idaho. 

^dAntiserum against YbST was raised in 10 female, adult (25- to 30-g), CD-1 albino mice (Charles River Laboratories, Inc., Wilmington, Mass.) by subcutaneous administration of a water-in-oil emulsion (0.2 ml) composed of equal parts of boiled Y. bercovieri 6519 CSF (concentrated ca. 100-fold by ultrafiltration with a 3-kDa cut-off membrane) and Freund incomplete adjuvant. The mice received injections on day 0 and at weeks 5, 9, and 11 and were exsanguinated 1 week after the last injection. The sera were pooled, heat treated (56°C; 30 min), and stored at 4°C. 

^eND, not done.