Figure 1.

Susceptibility to Leishmania major infection of amino acid (aa)-fed C57BL6 mice. (a) Casein-fed BALB/c (○), aa-fed C57BL/6 (Δ) or casein-fed C57BL/6 (▪) mice were infected with L. major promastigotas (1 × 10⁶). Lesion size was monitored for 12 weeks and is expressed as the difference in thickness between the infected and the uninfected contralateral footpads. Numbers of lesion parasites at 7 (b) or 12 (c) weeks of infection were determined by limiting dilution assay and are expressed as the negative log₁₀ dilution in casein-fed BALB/c mice (white bars), casein-fed C57BL/6 mice (black bars), and aa-fed C57BL/6 mice (grey bars) infected with L. major. Values are the mean ± standard error of the mean for five mice per group and are representative of results of two separate experiments. Asterisks or different letters show statistical difference between groups of C57BL/6 mice (P < 0·05).