Inhibition of <i>A</i>. <i>phagocytophilum</i> infection by antibodies against over-represented proteins.

<p>The antibodies against surface-exposed proteins, GroEL, HSP70 and MSP4, were used to characterize the inhibition of pathogen infection in ISE6 tick cells. Tick cells were treated with different rabbit antibodies and then infected with <i>A</i>. <i>phagocytophilum</i> (NY18). Treatments included rabbit pre-immune serum, anti-<i>A</i>. <i>phagocytophilum</i> GroEL, HSP70 and MSP4 protein antibodies and anti-tick Porin antibodies. Untreated cells were left uninfected or infected with <i>A</i>. <i>phagocytophilum</i> (NY18). <i>A</i>. <i>phagocytophilum</i> infection levels were determined by <i>16S rDNA</i> and <i>msp4</i> PCR and normalized against tick <i>16S</i> mitochondrial <i>rDNA</i> with similar results. Normalized <i>msp4</i> levels are shown in arbitrary units as Ave+S.D and were compared between infected and uninfected untreated cells and between infected cells treated with the pre-immune serum and antigen-specific antibodies by Student’s t-test with unequal variance (P<0.05; N = 4 replicates per treatment).