Histological observations of vascular lesions in groups treated with anti-ApoA2
The histology of arteritis in each experimental group is shown (Fig. 1). In the groups that were administered with the solvent, anti-ApoA2 0.05 mg/kg/day, or anti-ApoA2 0.1 mg/kg/day, severe panvasculitis encompassing the aortic roots, including coronary bifurcations, and abdominal and thoracic aortas was observed (Figs. 1A-C). Inflammatory cells, mainly consisting of neutrophils and histiocytes, accompanied by proliferation of fibroblasts and capillaries were observed in all the layers of the vessel walls. On the other hand, panvasculitis in the aortic roots could not be completely suppressed even in the group administered with anti-ApoA2 0.1 mg/kg/day and hIgG, but the extent of vasculitis was smaller than that in the solvent group. However, many segments without even a small degree of inflammation or with just mild inflammation, such as in endoarteritis, were also observed.
Although panvasculitis was observed in the abdominal aortas of the hIgG-administered group, this was not the case in the abdominal and thoracic aortas of the anti-ApoA2 0.1 mg/kg/day group (Fig. 1D-E). However, when panvasculitis developed in any of the treatment groups, the types and numbers of inflammatory cells infiltrating the lesion were similar to those of the solvent group.
Decreased Incidence Of Panvasculitis After Treatment With Anti-apoa2
We determined the incidence of panvasculitis in the coronary artery and aortic roots in each group via histological observation. Panvasculitis incidence in the different groups subjected to different treatments was 71.4% (5/7 mice) for solvent, 87.5% (7/8 mice) for anti-ApoA2 0.05 mg/kg/day, 75% (6/8 mice) for anti-ApoA2 0.1 mg/kg/day, 25% (2/8 mice) for anti-ApoA2 0.05 mg/kg/day, and 28.6% (2/7 mice) for hIgG 0.1 mg/kg/day (Fig. 2a). Groups administered with anti-ApoA2 0.5 mg/kg/day and hIgG 0.1 mg/kg/day showed lower incidence than that in the solvent group. Moreover, the incidence of whole body panvasculitis, based on the histological observations of the lung, spleen, kidney, heart and skin for each group was as follows: 100% (7/7 mice) for solvent; 87.5% (7/8 mice) for anti-ApoA2 0.05 mg/kg/day; 87.5% (7/8 mice) for anti-ApoA2 0.1 mg/kg/day: 25.0% (2/8 mice) for anti-ApoA2 0.5 mg/kg/day; 57.1% (4/7 mice) for native human IgG 0.1 mg/kg/day. Panvasculitis occurred in all the groups, but its incidence in the group treated with anti-ApoA2 0.5 mg/kg/day tended to be particularly lower than that in the solvent group. We specifically observed panvasculitis in some parts of the abdominal and thoracic aortas.
Decreased Inflammation In The 0.5 Mg/kg/day Anti-apoa2 Treatment Group
The degree of inflammation in each group, as indicated by the total score for all the 5 segments in each mouse, was as follows: 10.57 ± 2.52 for solvent; 9.25 ± 1.66 for anti-ApoA2 0.05 mg/kg/day; 8.88 ± 1.89 for anti-ApoA2 0.01 mg/kg/day; 3.13 ± 1.90 for anti-ApoA2 0.5 mg/kg/day; 4.14 ± 2.33 for hIgG 0.1 mg/kg/day (Fig. 3a). The degree of inflammation in groups treated with anti-ApoA2 0.5 mg/kg/day was significantly lower than that in the solvent group (P < 0.05), while that in all the treatment groups tended to be lower than that in the solvent group.
Effect Of Anti-apoa2 Treatment On The Extent Of The Lesion
The extent of the lesion, as indicated by the total number of lesion segments per 5 segments in each mouse, in each group were as follows: 3.71 ± 0.75 for solvent: 3.25 ± 0.53 for anti-ApoA2 0.05 mg/kg/day; 3.13 ± 0.61 for anti-ApoA2 0.01 mg/kg/day; 1.13 ± 0.67 for anti-ApoA2 0.5 mg/kg/day; 1.71 ± 0.75 for hIgG 0.1 mg/kg/day (Fig. 3b). The extent of the lesion in the treatment groups tended to be smaller than that of the solvent group.
Cytokines/chemokines In Serum
We made the comparison between the cytokine/chemokine profiles of healthy controls and KD models. The levels of the 24 cytokines and chemokines, IL-1β, IL-2, IL-3, IL-4, IL-5, IL-6, IL-9, IL-12p40, IL-13, GM-CSF, IFN-γ, KC, MCP-1, MIP-1α, MIP-1β, TNF-α, IL-15, IL-18, FGFbasic, LIF, M-CSF, MIG, MIP-2, and VEGF in the plasma of the KD mouse model induced by CAWS were significantly higher than those in the plasma of the healthy control. We focused on these 24 cytokine/chemokines in the treatment groups. The levels of inflammatory cytokines and chemokines, IL-1β, IL-2, IL-4, IL-5, IL-6, IL-12p40, IL-13, MCP-1, MIP-1α, TNF-α, LIF, M-CSF, MIG, MIP-2, and VEGF, in the anti-ApoA2 treatment groups tended to be lesser than those of the solvent group. However, the levels of the 24 cytokines/chemokines in the anti-ApoA2 0.05 and 0.1 mg/kg/day treatment groups failed to show statistically significant suppression. Nevertheless, the levels of inflammatory cytokines, such as IL-6 (P < 0.01), M-CSF (P < 0.005), and MIP-1α (P < 0.01) in the anti-ApoA2 0.5 mg/kg/day treatment group were significantly suppressed (Fig. 4).