Figure 4: Comparison of transmigration efficiency of different serotype 7F isolates using the HBMEC-BBB model. In addition to the 7F-liquor isolate1, a further cerebrospinal fluid isolate from meningitis patients (7F-isolate4), a non-invasive isolate from the nasopharyngeal cavity (7F-isolate2) and a blood isolate from a meningitis patient (7F-isolate3) were incubated with the HBMEC-BBB for 6 h using an MOI of 10. Transmigration rate and efficiencies were calculated by determination of transmigrated CFU after plating and overnight culture on blood agar plates. Results indicated higher transmigration efficiency for the cerebrospinal and blood isolates derived from invasive meningitis in contrast to less transmigration determined for the serotype 7F isolated as non-invasive colonizer from a healthy child. Statistical significance calculation determined a p-value of < 0.05 for differences between the non-invasive isolate 2 and the liquor isolate 1 from a meningitis patient.