OxyFile #158

Specific immunization using keyhole limpet hemocyanin-ganglioside 
conjugates.

Author:   Jennemann R; Gnewuch C; Bosslet S; Bauer BL; Wiegandt H 

Address:  Institut fźr Physiologische Chemie, 
          Philipps-UniversitŠt, Marburg, Germany. 

Source:  J Biochem (Tokyo), 1994 Jun, 115:6, 1047-52 

Abstract:

In a search for adjuvants of non-bacterial origin for immunization 
with ganglioside, we investigated whether chemical coupling to 
immune stimulatory protein could increase the immunogenicity of 
sialoglycosphingolipid. A novel method for the linkage of 
glycosphingolipids, including gangliosides, to protein was 
established. The procedure includes lysis of the sphingoid double 
bond by ozone, reduction of the ozonolysis product to the 
aldehyde, and coupling to amino groups, either directly by 
reductamination, or by conjugation via a long aliphatic chain 
dicarboxylic acid linker. Using this method, gangliosides Gfpt1 
(IV2-Fuc-, II3NeuAc-Gg4Cer), Glac2 [II3(NeuAc)2-LacCer], and Gtet1 
(II3NeuAc-Gg4Cer) were coupled to keyhole limpet hemocyanin (KLH), 
and the immunogenicity of the conjugates was tested. Immunization 
of mice with the KLH-ganglioside conjugates led in each case to 
the formation of IgG- and IgM antibodies that recognized the 
underivatized gangliosides, respectively. In contrast to this, 
mixtures of KLH and ganglioside proved ineffective for 
immunization. KLH-tumor-associated ganglioside conjugates may, 
therefore, be considered as possible vaccines in immune therapy of 
cancer.