Table 2. Intracellular Cytokine Expression to Antigen Stimulation.
| Malaria Antigen Poola | Schistosoma Antigen Poola | |||||||||
| Season | Cohort | Age (yrs) | IL-2 (%) | Pb | IFN-γ (%) | Pb | IL-2 (%) | Pb | IFN-γ (%) | Pb |
| Wet | SP | 4–8 | 0/6 (0) | ns | 1/6 (17) | ns | 2/6 (33) | ns | 2/6 (33) | ns |
| SNc | 1/5 (20) | 1/5 (20) | 1/5 (20)d | 1/5 (20)d | ||||||
| SP | 9–14 | 7/9 (78) | 0.02 | 4/9 (44) | ns | 7/9 (78) | 0.007 | 6/9 (67) | 0.003 | |
| SN | 2/10 (20) | 3/10 (30) | 0/10 (0) | 0/10 (0) | ||||||
| SP | 4–14 | 7/15 (47) | ns | 5/15 (33) | ns | 9/15 (60) | 0.002 | 8/15 (53) | 0.005 | |
| SN | 3/15 (20) | 4/15 (27) | 1/15 (7) | 1/15 (7) | ||||||
| Dry | SP | 4–8 | 2/6 (33) | ns | 1/6 (17) | ns | 4/6 (67) | 0.06 | 2/6 (33) | ns |
| SN | 4/5 (80) | 2/5 (40) | 0/5 (0) | 0/5 (0) | ||||||
| SP | 9–14 | 6/11 (55) | 0.06 | 7/11 (64) | 0.02 | 9/11 (82) | <0.001 | 7/11 (64) | 0.001 | |
| SN | 2/12 (17) | 2/12 (17) | 0/12 (0) | 0/12 (0) | ||||||
| SP | 4–14 | 8/17 (47) | ns | 8/17 (47) | 0.16 | 13/17 (76) | <0.001 | 9/17 (53) | 0.0009 | |
| SN | 6/17 (35) | 4/17 (23) | 0/17 (0) | 0/17 (0) | ||||||
Results of intracellular cytokine expression after antigenic stimulation of PBMC acquired from age-matched children with (SP Mal) or without S. haematobium (SN Mal) during the malaria transmission (wet) season at the time of a malaria episode and again during a dry season follow-up visit. The numerator results represent those individuals with statistically significant increases in the percentage of cytokine expressed compared to media controls after PBMC stimulation and the denomenator represents the total number of individual PBMC samples analyzed.
PBMC were stimulated with a malaria antigen pool (Apical Membrane antigen 1 and Merozoite Surface Protein 1) or with a S. haematobium pool (soluble egg antigen and soluble worm antigen protein). SP no Mal children were not included in this analysis.
χ2 analysis, using Mantel-Haenszel or Fisher Exact (two-tailed) as appropriate, was performed between S. haematobium positive (SP Mal) vs. S. haematobium negative (SN Mal) children in each age category. P value significance set at <0.05. Not significant = ns.
Three experiments were excluded due to insufficient or poor viability cell quantities to allow proper interpretation of data.
IL-2 and IFN-g production was noted in one SN individual. Urine was negative for eggs both at enrollment and at dry season follow-up suggesting a false positive result.