FIG 2 .

Constitutive expression of bbd18 prevents induction of ospC in feeding nymphs. Immunofluorescence microscopy of spirochetes within replete I. scapularis nymphs. Spirochetes in fed nymphs, infected as larvae with S9 (WT, top) or S9/pBSV2*flaBp-bbd18 (WT+cBBD18, bottom), were assessed at detachment from the host. Crushed ticks were costained with a mouse monoclonal antibody recognizing OspC (left) and polyclonal rabbit serum that detects all B. burgdorferi (middle); merged images are shown in the right panels. Scale bars as shown in the upper right panel apply to all images, and inset boxes represent 2-fold magnification of a comparable area in all 3 panels for each strain.