| Research Abstract |
The purpose of this study is to utilize hematopoietic stem cells as a vehicle of the anti-inflammatory cytokines in the arthritic model mice. T cells derived from these hematopoietic stem cells must go preferentially to the inflammed joints in order to take better effect. Two putative genes were chosen : chemokine receptor (CCR4) and IL-10. The former is to direct T cells to the inflammed joints and the latter is for anti-inflammatory effect. These genes need to be transfected simultaneously in a single hematopoietic stem cell.
As a preliminary experiment, peripheral T cells were used instead of hematopoietic stem cells from bone marrow, because transfection efficacy is much better for peripheral T cells than for hematopoietic stem cells. Gene for green fluorescent protein (GFP) was incorporated into retrovirus and was transfected to peripheral T cells as a reporter gene along with chemokine receptor or IL-10. Transfection efficacy was increased to "30% from 10% by repeating transfection processes on the fibronectin-coated plate including anti-CD3 and anti-CD28 antibodies.
Arthritic model mice were made by subcutaneous injections into DBA/1 mice of bovine type II collagen emulsified with Freund's complete adjuvant, booted with the same antigen in incomplete adjuvant 3 weeks afer the first immunization. By the biginning of the fourth week, many joints from immunized mice began to swell and arthritis became evident. However, the severity and the frequency of the artificial arthritis made by this method were quite diverse and, therefore, evaluation of the effectiveness of the treatment is quite difficult. Experimentation to overcome this issue is now undergoing.
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