[Research of immunogenity of allogenic keratinocytes]

To observe the change of the immunogenity of keratinocytes when cultured in vitro.

Health children foreskins were digested by dispase and trypase. The human keratinocytes were cultured in vitro and passaged in succession until the fifth passage. Different passage keratinobytes signed by SP method to show the percentage of langerhans cells and melanocytes. Every passage keratinocytes were respectively mixed with allogenic lymphocytes which isolated from peripheral blood, and then the proliferation degree of allogenic lymphocytes was tested.

Keratinocytes were cultured well in K-SFM medium. When keratinocytes conjugated, every passage cells grew like paving stone. After cryopreservation and then rewarming, the survival exceeded 80%. The percentages of langerhans cells and melanocytes in the primary passage were 5.8% and 8.1% respectively. In the 1st passage they were 2.1% and 2.8% respectively. They were not detected in the second passage. The values of cpm were respectively 482.13 +/- 46.61 (primary passage), 362.50 +/- 35.12 (1st passage), 228.38 +/- 51.46 (2nd passage), 171.86 +/- 34.63 (3rd passage), 143.63 +/- 15.95 (4th passage), and 123.25 +/- 14.39 (5th passage), showing statistically significant differences when compared with control (53.67 +/- 8.61) (P < 0.05). There were statistically significant differences between the primary passage, the 1st passage respectively and the other passages (P < 0.05). There were statistically significant differences between the 4th passage, the 5th passage respectively and the 2nd passage (P < 0.05). There was no statistically significant difference between the 2nd passage and the 3rd passages (P > 0.05). There was not statistically significant difference among the 3rd, the 4th and the 5th passages (P > 0.05).

Allogenic keratinocytes were cultured in vitro and passaged, and their immunogenity gradually decreased.