Table 1. The addition of rIL-5 increased parasite fecundity independently of IL-4.

	BSA	rIL-5
BALB/c	28.5±6.6	66.7±14.1
BALB/c IL-4−/−	254.8±83.4	425.6±189.2

BALB/c mice, n = 16 per group pooled from three experiments (no significant variation between experiments), and BALB/c il-4 ^−/− mice, n = 6 per group, were infected subcutaneously with L. sigmodontis larvae that were allowed to develop and reproduce for 150 d. Numbers represent mean cumulative microfilarial loads ± s.e.m. Effects of rIL-5 treatment and of mouse strain were both significant (p = 0.009 and p<0.0001, respectively), and there was no interaction between treatment and strain (negative binomial glm).