them reacted distinctly with sera from mature 

 females of all teleost species tested. Figure 1 

 illustrates the reactions of sera from mature 



Figure 1. — Reactions of sera from mature females of 

 six teleost species with rabbit anti-RM serum. Peri- 

 pheral wells contain sera from 1, copper rockfish; 

 2, sand sole; 3, bigeye tuna; 4, Pacific cod; 5, carp; 

 6, sockeye salmon. 



female teleosts of six different families when 

 tested with the anti-RM reagent. The strongest 

 reaction was with the female rockfish serum. 

 The degree of cross-reactivity regularly de- 

 creased through the somewhat distantly related 

 salmonoids and cyprinoids. Even in these 

 groups, however, the reaction was clear. 



ponents. The SM vitellin cross-reacts com- 

 pletely with the antibodies directed against one 

 of these components. Two components are 

 visible in figure 2b that react with the anti- 

 SM antiserum. The RM vitellin cross-reacts 

 partially and very weakly with the antibodies 

 directed against one of these components. 



Table 3. — Results of ahsorption^ of rahhil anlirochfish riieUin 

 (RM) serum with sera of mature female teleosts 



Comparisons similar to those presented in 

 figure 2 were made between the broadly cross- 

 reactive antisera (anti-RM and anti-HM), the 

 less cross-reactive antisera (anti-CLM, anti- 

 SM, anti-CM, and anti-GM), and the cor- 

 responding vitellins. All results were similar. 

 The weak or negative reactions of the RM and 

 HM vitellins with the less cross-reactive or 

 group-specific antisera contrasted with the 

 strong reactions of the anti-RM and anti-HM 

 antisera with the vitellins which elicited the 

 less cross-reactive antisera present an interest- 

 ing serological phenomenon. The cross-reactive 

 antibodies of the anti-RM and anti-HM anti- 

 sera apjear to have a considerably greater 

 avidity for the vitellins which elicit group- 

 specific antisera than the group-specific anti- 

 bodies have for the RM and HM vitellins. 



Table 3 gives the results of absorptions of 

 the anti-RM reagent with the fish sera of figure 

 1. It is evident from both figure 1 and table 3 

 that the anti-RM reagent contains antibodies of 

 numerous specificities. 



Figure 2 presents a more detailed examina- 

 tion of the relationship between SM and RM 

 vitellins. It is evident from figure 2a that the 

 RM vitellin has at least three distinct com- 



Both the homologous and cross-reaching 

 heterologous antisera gave uniform results 

 where tested with a larger number of individ- 

 uals. Randomly selected sera from 48 sockeye 

 salmon were tested with anto-SM, anti-RM, and 

 anti-HM reagents; 48 halibut sera were tested 

 with the anti-RM and anti-HM reagents. Re- 

 sults were identical regardless of the antiserum 

 used, including two weak but positively react- 

 ing halibut sera. 



CROSS-REACTIVE PROPERTIES OF ANTISERA 



205 



