Study on the Kinetics of Ia Antigen Positive Dendritic Cells in Mouse Lymph Nodes in Contact Hypersensitivity Reaction

Abstract

C3H/He NCrj mice were sensitized with 1-chloro-2, 4-dinitrobenzene (DNCB), challenge reactions were induced, and lymph nodes were sampled at specified time intervals. Using these as materials, the kinetics of Ia antigen positive dentritic cells (Ia-D cells) in lymph nodes were studied histologically and by the immunoperoxidase method. The following findings were obtained. 1) From 24th hours after induction, Ia-D cells increased in number around the marginal sinus. After 48 hours, they also increased around the medullary sinus. 2) On the fourth day after induction, an increase of Ia-D cells was noted in the paracortex. 3) Four hours after challenge, the number of Ia-D cells in the paracortex under 400 power magnification was about ten times that of untreated mice. In the measurement by image analyzer, the former was about six times that of the latter. 4) The number of Ia-D cells in the paracortex reached the peak four hours after the challenge, and thereafter decreased gradually to 48 hours. However, 24 hours after challenge, the Ia-D cells began to appear again around the marginal sinus, and after 96 hours, the number of Ia-D cells in the paracortex again started to increase and then to decrease with time. The following conclusions may be arrived at from the results of the present experiment. 1) In the induction phase, Ia-D cells are supplied into the lymph nodes through afferent lymphatics, and at first increase in number in the marginal sinus. In the next stage, these Ia-D cells gradually move into the paracortex. 2) In the challenge phase, Ia-D cells increase in number first in the paracortex, and then after 24 hours, increase also in the marginal sinus. 3) It is believed that increased Ia-D cells in the lymph nodes play a role in contact hypersensitivity in both induction and challenge phases. 4) It is probable that Ia-D cells are either veiled cells, Langerhans cells, or interdigiting reticulum cells. © 1986, Meeting of Osaka Dermatological Association. All rights reserved.