OBJECTIVETo study the effect of blister fluid obtained from burn patient on human MSCs in vitro and its phenotypic modulation in culture.

METHODSBlister fluid from burn patients was collected at 12, 24, 48 post burn hour (PBH). The human MSCs were isolated, cultured, amplified and identified in vitro, then were divided into A (culture with 20% blister fluid collected at 12 PBH) , B (culture with 20% blister fluid collected at 24 PBH), C (culture with 20% blister fluid collected at 48 PBH), N (with ordinary culture medium) groups. The growth of MSCs and micro-organisms in blister fluid were observed. Positive expression rates of CD44 and CK7 were detected by flow cytometry after culture for 8 days.

RESULTSBacterial and fungal growths were absent in 15 blister fluid samples. There was no obvious change in MSC morphology in each group. Compared with that of N group, the number of MSCs in A, B, C groups was decreased, especially in C group. CD44 positive expression rate in A, B, C groups was (83.0 +/- 3.1)%, (77.2 +/- 2.9)% and (65.1 +/- 2.3)%, respectively,which was obviously lower than that in N group [(89.5 +/- 3.2)%, P < 0.01]. CK7 positive expression rate in A, B, C groups was (24.06 +/- 0.11)%, (16.41 +/- 0.09)% and (4.48 +/- 0.07)%, respectively, which was obviously higher than that in N group [(3.87 +/- 0.04)%, P < 0.01].

CONCLUSIONSBurn blister fluid can obviously inhibit the growth of human MSC cultured in vitro, and may promote modulation of its phenotype to certain extent.