The profile of IgG and IgG subclasses of onchocerciasis patients

Abstract
In this study Onchocerca gutturosa was compared with O. volvulus in an ELISA test to detect Onehocerca- spefic IgG and IgG subclasses. The test was developed and standardized to detect Onehocerca-spefic IgG and IgG subclasses in sera of onchocerciasis patients and endemic controls. Onchocerca volvulus and O. gutturosa crude water-soluble antigens showed no significant difference in detecting onchocerca-specific IgG antibody (T = 1·88, P > 0·05). The levels of IgG subclasses varied greatly. IgG4 showed the highest detected mean level (0·84 ± 0·59) and the other three subclasses showed considerably lower mean levels (IgGI =0·27±0·16, IgG2 = 0·24 ± 0·17, IgG3 = 0·28 ± 0·12). The status and score of skin lesions were found to have significant effect on the IgG and IgG subclasses levels (all P < 0·001). lgG4 showed a positive correlation with the microfilarial (Mf) load (r= 0·21, P < 0·03). IgG3 levels have a significant negative correlation with the Mf load (r=-0·23, P <0·02), The biological significance of these IgG and IgG subclasses in onchocerciasis is discussed.