[Immunogenicity of allogeneic freezing periosteum and bone marrow]

To investigate the immunogenicity of freezing periosteum and bone marrow during allogeneic joint transplantation, and to explore proper pretreatment of allogeneic joint.

The allogeneic periosteum and bone marrow were harvested from knee joints of 5 New Zealand white rabbits (aged, 6 months; weighing, 2.6-3.0 kg). After gradient cooling, the tissue was cryopreserved for 1 month. The freezing periosteum and bone marrow were grinded to pieces after rewarming to prepare the suspension of periosteum and bone marrow. Eighteen Chinchilla rabbits (aged, 6 months; weighing, 2.1-2.8 kg) were divided into 3 groups randomly: normal saline injection group (group A, n = 6), periosteum injection group (group B, n = 6), and bone marrow injection group (group C, n=6). The normal saline, periosteum suspension, and bone marrow suspension were injected into the peritoneal cavity in groups A, B, and C, respectively. The concentrations of interleukin 2 (IL-2), IL-6, and tumor necrosis factor alpha (TNF-alpha) in serum and the ratio of CD4' T cell/CD8+ T cell in venous blood were measured before injection, at 1 week and 2 weeks after injection.

There was no significant difference in the concentration of IL-2 between before and after injection in the same group (P=0.241), and between groups (P = 0.055). The concentration of IL-6 after injection was significantly lower than that before injection in the same group (P = 0.040), but no significant difference was found between groups (P = 0.357). The concentration of TNF-a showed no significant difference between before and after injection in the same group (P = 0.925), but the concentration of TNF-a in group B was significantly higher than that in groups A and C (P < 0.05). The ratio of CD4+ T cell/CD8+ T cell of venous blood had no significant difference between before and after operation in the same group (P = 0.248), and between groups (P=0.646).

The freezing periosteum and bone marrow are lowly immunogenic. In order to decrease the immunogenicity of the joint, preserving the periosteum and removing the marrow cavity are recommended.