Fig 1.
Representative photographs of hamsters following percutaneous infection, Experiment 1.
Left panel shows the application of larvae to the abdominal area using an adhesive bandage as described in the Materials and Methods. Remaining panels show animals two days after infection with the indicated number of hookworm larvae. Dotted lines indicate extent of skin reaction to larval penetration.
Fig 2.
Pathology, worm burden and fecal egg output following percutaneous infection (Experiment 1).
Hamsters (n = 3 each group) were infected with the indicated number of A. ceylanicum L3 by oral or percutaneous (PERC) route. Mean blood hemoglobin levels +/- Standard Deviation (SD) are presented in [A], intestinal worm burdens at day 22 PI are shown in [B] as absolute numbers (left) or yield expressed as percent of inoculum (right), and mean fecal egg output in [C] as calculated per gram of feces (EPG) recovered from the large intestines of individual animals (left) or EPG per recovered worm (right). Symbols in [A] indicate level of statistical significance by Fisher’s Least Significant Difference post-test following a two-way ANOVA: for the comparison to uninfected (0 L3) animals * indicates P< 0.05. For the comparison of 1000 L3 percutaneous and 5000 L3 percutaneous groups, △ indicates P< 0.05. In [B] and [C] brackets indicate statistically significant comparisons by one-way ANOVA, with P values given above the brackets.
Fig 3.
Intestinal worm burden and worm lengths following percutaneous infection (Experiment 2).
Hamsters (n = 9 each group) were infected with 100 L3 by the oral route or 2000 L3 by the percutaneous (PERC) route. At days indicated, three animals from each group were sacrificed and intestinal worms recovered, counted and measured. Mean +/- SD intestinal worm burdens at each time point are shown in [A], worm length at each time point in [B] and representative photographs of worms recovered at each time point in [C]. In [A] and [B] brackets indicate statistically significant comparisons by Welch t test, with P values given above the brackets.
Fig 4.
Organ weight and cellular data following percutaneous infection (Experiment 2).
Hamsters (n = 9 each group) were infected with 100 L3 by the oral route or 2000 L3 by the percutaneous route. At days indicated, 3 animals from each group were sacrificed and organs recovered, weighed, and lymphocytes analyzed by flow cytometry. For the spleen, mean organ weights are shown in [A], percentage of blasting lymphocytes in [B], percentage of CD4-positive lymphocytes in [C] and percentage of IgG-positive lymphocytes in [D]; the corresponding data for mesenteric lymph nodes is shown in [E-H]. In all panels brackets indicate statistically significant comparisons by Welch t test, with P values given above the brackets. Bars represent Mean values +/- SD.
Fig 5.
Pathology and fecal egg output following percutaneous infection (Experiment 3).
Hamsters (n = 6 each group) were infected with the indicated number of L3 by oral or percutaneous route. Mean blood hemoglobin levels over time are presented in [A], weight change over time in [B] and pooled fecal egg output in [C]. Data points represent Mean +/- SD. Symbols in [A] and [B] indicate level of statistical significance by Fisher’s Least Significant Difference post-test following a two-way ANOVA: for the comparison to 0 L3 * indicates P< 0.05. For the comparison of 50 L3 oral and 1000 L3 percutaneous groups, △ indicates P< 0.05.
Fig 6.
Hookworm-specific antibody responses following percutaneous infection (Experiment 3).
Hamsters (n = 6 each group) were infected with the indicated number of L3 by oral or percutaneous route. Specific IgG titers against soluble larval extract (LEX) in pooled hamster sera are presented in [A], titers against adult worm excretory-secretory (ES) antigens are presented in [B], and rAceES-2-specific titers in [C]. Data points represent Mean +/- SD.