HLA-A and neoplasm: Since ‘exosomes’ have been shown to exhibit HLA antigens and tumour-associated antigens, the presence of specific antigens was confirmed on ascites-derived ‘exosomes.’ These ‘exosome’ isolates expressed HLA-A antigens at similar levels (Figure 3A), as well as expressing two tumour-associated antigens (PLAP and B23) (Taylor et al, 1984; Gerçel-Taylor et al, 2001) that have previously been demonstrated to be present on membrane vesicles isolated from both peripheral blood and ascites (Taylor et al, 1980, 2002, 2003) and to generate humoral responses in autologous patients (Figure 3C and D).