In vitro invasion inhibition assay using antibodies against Plasmodium knowlesi Duffy binding protein alpha and apical membrane antigen protein 1 in human erythrocyte-adapted P. knowlesi A1-H.1 strain

Table 1 IgG responses of knowlesi-infected patients’ serum samples to PkDBPα and PkAMA1 recombinant proteins

Samples	No. of patient samples (n)			Normalized MFI^e	No. of healthy samples (n)			Normalized MFI^e
Samples	Positive^a	Negative^b	Total (%)^c	Normalized MFI^e	Positive^a	Negative^b	Total (%)^d	Normalized MFI^e
PkDBPα	2	13	15 (13.0)	0.76	0	19	19 (100.0)	0.72
PkAMA1	7	8	15 (46.7)	0.92	0	19	19 (100.0)	0.67

^aPositive: the individual who is reactive to its particular antigen
^bNegative: the individual who is not reactive to its particular antigen
^cSensitivity: percentage of positive-malaria patient samples
^dSpecificity: percentage of negative-healthy individual samples
^eNormalized MFI: mean fluorescence intensities were divided by a cut-off value + 2 standard deviations above the mean fluorescence intensity of the malaria-naïve samples

ISSN: 1475-2875