3.7 Infiltration of ILC2s and neutrophils at the site of
attachment of ticks
Infiltrations of macrophages and basophils had been detected at the site
of attachment of ticks (6,14). However, ILC2s are abundant in skin and
are responsible to provide innate immunity against parasitic infections
(15,16). Therefore, we planned to detect responsiveness of ILC2s at the
tick bitten areas. For this, we collected skin samples from the sites
tick attachment or non-infested wt or RAGE-/-mice and subjected to immune-histochemical analysis using anti-CD44. Our
study revealed massive infiltration of CD44+ cells at
the tick bitten lesion. Infiltration of the cells increased in the
subsequent infestations and the highest infiltrations were detected
during the tertiary infestations. However, accumulation of
CD44+ cells was minimum during the feeding process of
ticks on RAGE-/- mice, indicating the important
role of RAGE on the trafficking of ILC2s at the attachment sites (Figure
4). Furthermore, infiltrations of neutrophils were detected by
immune-histochemistry using anti-MPO. Very few anti-MPO-positive cells
were found both in wt and RAGE-/- mice skin
(Figure 5), indicating that neutrophils has no significant roles in the
tick-inflicted injuries in skin.