Biomedical Engineering Reference
In-Depth Information
antibodies, the composite was recognised by the antibodies equally well as
the free peptide. Therefore, the experiments revealed that the epitope was
appropriately presented after conjugation with mono- (compound
4
) and
bis-derivatised (compound
6
) CNTs as measured by BIAcore technology. As
concerns this last aspect, surface plasmon resonance (SPR) on a BIAcore
instrument enabled the analysis of antigen-antibody interactions in real
time and with high sensitivity. Interestingly, CNTs functionalised but not
conjugated to the peptide moiety were not recognised. This important inding
indicated that no anti-CNT antibodies were detected, suggesting the absence
of cross-reactivity with the CNTs.
Moreover, since the peptide under investigation lacked the ability of
eliciting an immune response (immunogenicity) in BALB/c mice, additional
carrier proteins or T-cell epitope (provided by ovalbumin [OVA] in a Freund's
emulsion) were employed. After two co-injections, strong anti-peptide
antibody responses were induced, showing higher virus-neutralising capacity
than the antibodies elicited after co-immunising the free peptide with OVA
(Fig. 4.3).
7
This inding highlights the potential of functionalised CNTs to act
as a delivery system capable of presenting critical epitopes at an appropriate
conformation to elicit antibodies with the right speciicity.
Free peptide
Free
Compound
4
Compound
6
Free peptide+
Acetylated
Compound
4
f-
CNT
4
f-
CNT
6
Free peptide
peptide
+ Ac-CNT
4
Figure 4.3
Anti-peptide antibody responses following immunisation with peptide
and peptide-CNT conjugates. Serum samples were screened by ELISA for the presence
of antibodies using FMDV 141-159 peptide conjugated to BSA (cyan bar), control
peptide conjugated to BSA (magenta bar) or CNTs 1 functionalised with a maleimido
group without peptide (white bar) as solid-phase antigens. Reproduced from Davide
Pantarotto
et al.
7
with permission. See also Colour Insert.
A similar approach was adopted for the incorporation of another peptide
to be used against
Plasmodium vivax
in the treatment of malaria.
8
Plasmodium
is a parasite that contains a very highly conserved trans-membrane protein
called AMA-1, which consists of 562 amino acids,
9
with an extracellular N-
terminal domain, an ectodomain, a trans-membrane region and a C-terminal
Search WWH ::
Custom Search