SOJ Immunology

1

Authors: Malyshkin AP

Organ transplantation entails numerous problems. It is hardly possible to find an absolutely compatible donor, and graft protection through immunosuppression decreases the recipient’s resistance to infections. New views on immunity summarized in the concept of linked functions offer a different approach to preventing graft rejection. According to it, genes of the donor’s MHC antigens are integrated into the genome of the recipient’s hematopoietic stem cells. It is expected that, in this case, the recipient’s immune system will recognize the transplant as self and will not reject it.

4

Authors: Gregory Lee, Cheng-Yuan Huang, Suefay Liu and Hao Zhang

RP215 is a monoclonal antibody discovered in 1987 which was later found to react specifically with a carbohydrate-associated epitope detected mainly among immunoglobulin heavy chains from cultured cancer cells. With RP215 as the unique probe for cancerous immunoglobulins, the experimental evidences seem to suggest that the immunology of cancer cells plays dramatic roles in the growth/ proliferation and immune protection of cancer cells. RP215-specific cancerous immunoglobulins serve in part to capture or neutralize circulating antibodies or antigen hostile to cancer cells in human body. In the conventional immune system, B and T lymphocytes and their associated antigen receptors play key roles in the adaptive immune response against pathogens and/or cancer cells through established mechanisms. In contrast, cancer cells co-express both B and T lymphocyte-associated antigen receptors and immune protection is exercised by completely different mechanisms. For example, these cancer cell-expressed antigen receptors demonstrate a lack of class switching, or limited hyper mutation. Furthermore, toll-like receptors involved in the innate immune system in cancer cells are strongly affected by these cancer cell-expressed antigen receptors. Therefore, both normal and cancerous immune systems can co-exist and can be operated simultaneously within the human body. A potential therapeutic strategy may be developed by using RP215 as a drug candidate to target cancer cells based on these observations.

4

Authors: Elodie Begue, Laurence Michel, Francette Jean-Louis, Martine Bagot and Armand Bensussan

Previous studies about the mechanism responsible for the regulation of PLS3 gene expression in cutaneous T cell lymphoma suggested a possible role of DNA methylation in the control of tissuespecific expression of PLS3. Using methylation-specific polymerase chain reaction adapted for quantitative real-time PCR, the present study investigated the methylation status in two human lymphocyte cell lines derived from tumor lymphocytes of patients with Sezary syndrome, HuT-78 cells which express PLS3 mRNA and SeAx cells that do not, and used well-established inhibitor of DNA methylation, the nucleoside analog 5-aza-2-deoxycytidine (5-aza-dC), to further determine its effect on PLS3 gene expression in both cell lines. Our results clearly revealed a quantitative relationship between the methylation status of the PLS3 CpG region and PLS3 expression in HuT-78 and SeAx Sezary cell lines.