Figure 1
From: Defining immune correlates during latent and active chlamydial infection in sheep
Experimental overview of cellular assays in relation to experimental inoculations withChlamydia abortusand subsequent pregnancy. The experimental timeline of 36 weeks represented in the diagram with the timing of the cellular assays carefully selected to monitor responses pre-inoculation to post-parturition. Five time points were chosen for this, to correspond to pre-inoculation (week 0), pre-synchronisation and mating (week 6), pre-positive sub-cutaneous (s/c) control (group 5) challenge to coincide with early pregnancy of the intranasal inoculation (i/n) groups (week 17), pre-expected abortion period (week 22) and finally post-abortion/lambing (week 36) where these are represented by grey arrows. The week of the study is anchored by the i/n at week 0. For clarity, the pre-inoculation bleed is referred to as occurring at week 0 and not week −2, consistent with the paper describing the experimental model [8]. The five cellular bleeds for the s/c positive control Group 5 are simultaneously referred to the following week numbers: −21, −11, 0, 5 and 19. The orange arrow represents the timing of i/n with Chlamydia abortus (C. abortus) of the sheep: Group 1, 5 × 103 infection forming units (IFU)/mL, low dose; Group 2, 5 × 105 IFU/mL, medium dose; Group 3, 5 × 107 IFU/mL, high dose group and group 4, sham inoculation group (no C. abortus). The blue arrow represents the subcutaneous inoculation at day 70 of gestation of group 5 with 2 × 106 IFU/mL over the left pre-femoral lymph node. Red line represents the duration of pregnancy from week 12 to week 33. The orange line represents when the abortions took place and the brown line the period of time when the lambing occurred in all groups.