CD86 is a well-known costimulatory molecule related to the stimulatory activity of DCs. Thus, we next examined the expression of CD86 on the DCs from the cervical lymph nodes (draining lymph node), and compared it with that on the DCs from the inguinal lymph node by flow cytometry. As shown in
Figure 5D (histogram), there was a higher expression of CD86 on the DCs prepared from the cervical lymph nodes of scopolamine-injected mice, but not on DCs from the cervical lymph nodes in PBS-injected mice, or on the DCs from the inguinal lymph node in the PBS-injected mice and in the DCs from the inguinal lymph node in the scopolamine-injected mice (
Figs. 5C,
5E,
5F). This was the case when the MFI shifts were examined; MFI shifts of the DCs from the inguinal lymph nodes were not significant, that is, 0.97 on day 2, 1.01 on day 4, and 1.1 on day 7, after the scopolamine injections (closed circles in
Fig. 6). These findings suggest that the DCs of the inguinal lymph nodes were not activated (
Fig. 6). Thus, the increase in the expression of CD86 was not observed in DCs from the inguinal lymph nodes indicating that DC are not activated in the nondraining lymph nodes. On the other hand, the shifts in the MFI of the DCs from the cervical lymph nodes were increased to 2.12 on day 2, to 2.25 on day 4, and to 1.54 on day 7 after the scopolamine injections (closed diamonds in
Fig. 6). There were significant differences between cervical lymph nodes and inguinal lymph nodes on day 2 (
P < 0.01) and 7 (
P < 0.05), clearly indicating that the DCs in the cervical lymph nodes were activated by the scopolamine injections. The MFI shift decreased to 1.21 at 14 days in the DCs from the cervical lymph nodes obtained from the mice that were treated with scopolamine for 7 days and no injections for 7 days (closed diamond in
Fig. 6). There was a significant difference of MFI shift between day 4 and day 14 (injection for 7 days and followed by no injection for 7 days) (
P < 0.05).