Table 1

Choice of Purification Method for high yields is dependent on the species.

Sample
Purification
method
Average Conc.
(mg/mL)1
Mean ELISA Titer2
Recovery of Ag-
specific Igs (%)3
Purity of Ig
preparation (%)4
Stability at
4°C5


Pre-purification
1.3 × 106 (1.9 × 105)



Immune Rabbit
CA-AS
12.3
1.4 × 106 (3.6 × 105)
100
> 95%
NT

SEP-EASE (PEG)
10.9
1.1 × 106 (9.6 × 104)
85
> 95%
NT

Protein A/G
8.9
1.1 × 106 (6.3 × 104)
84
> 95%
NT

Protein G
14.3
1.8 × 106 (2.0 × 104)
100
> 95%
NT

Malaria-Exposed Human
Pre-purification
1.1 × 104 (962)




CA-AS
12.3
1.2 × 103 (176)
11*
> 95%
Yes

SEP-EASE (PEG)
14.5
1.6 × 104 (4 × 103)
100
> 95%
Yes

Protein A/G
14.4
4.8 × 103 (95)
44*
>95%
No

Protein G
19.8
6.6 × 103 (2.1 × 103)
60
> 95%
No

Data expressed as mean (± SEM) of three independent purification experiments.

1Protein concentration was determined by the absorbance of the solution at 280 nm with an extinction coefficient of 13.5 (standard for IgG) for a 1% IgG solution (10 mg/mL)

2Mean ELISA titer for an OD405 = 1, for rabbits tested against MSP1-p42(FVO) plate antigen, for humans tested against MSP1-p42(3D7) plate antigen

3Recovery of Ag-specific Igs is based on Mean ELISA titer.

4Determined by scanning densitometry on Coomassie Blue stained gels

5Samples were stored for 24 weeks at 4°C and then tested by SDS-gelelectrophoresis, NT = not tested

*A statistically significant difference between the methods in the recovery of Ag-specific Ab by ANOVA. The individual groups were isolated with a Tukey's post test (p < 0.025).

Bergmann-Leitner et al. Malaria Journal 2008 7:129   doi:10.1186/1475-2875-7-129