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October 2003

In Norther Ireland, at the beginning of the year, first clinical trial of effectivenes of polysulphate pentosan have started. The patient was Johnatan Simms, 18, from Belfast, who for several years suffers from vCJD. The pentosan was applied directly into the brain, and few days ago, scientist urged that it could effectively reduce progression of vCJD. For now, no deteiled information is available on this experiment, but it publishing is expected. Although pentosan has never been used to treat vCJD, there were some experiments in Japan conducted on rats infected with scrapie, which have shoved that pentosan effectively reduces accumulation of prions. Considering that vCJD is human variant of disease known as bovine spongioformn encephalopathy, possible pathway of pentosan activity in brain could be seen on the level of prion polymerization and accumulation. It would be interesting to conduct investigations which could show does pentosan have any influence on expression of PRNP gene in humans, and also, does it have any influence on prion accumulation in patients with fatal familial insomnia, syndrome Gerstmann-Straussler-Scheinker, Kuru or Alzheimer's disease.

September 2003

The investigation on SARS in Taiwan is conducted during epidemic, where many health workers were infected. The main goal of investigation was, on the human leukocyte antigen system, to establish a screening program for high risk personal. Two classes of HLA antigen, I and II, in case and control groups were used to examine the association to a genetic susceptibility or resistance to SARS coronavirus infection. On 37 patients of probable SARS cases was implemented HLA-class I and II allele typing by PCR-SSOP of which 28 patients were excluded later as probable SARS patients. There were also 101 non-infected healthcare workers who were exposed to SARS coronavirus infection. A control group was established with 190 healthy Taiwanese who were not exposed to SARS infection. The two types of HLA-class were isolated, type HLA-B*1301 and type HLA-B*4601. Results have shown that HLA-B*4601 antigen is associated to higher risk of getting severe form of SARS that is specific for Asian population.

New approach for AIDS treatment was suggested in early September by researchers from UCLA. They have discovered a novel mechanism which could be used to reveal latent T cells which are hosts for HIV. In such a cells HIV could be hidden for many years and protected from immune response. The chemical prostratin and human cytokine IL-7 could induce proliferation of T cells without any significant effect on their phenotype. Both, the prostratin and IL-7 are agents which cannot induce cancer, but they are usable as inducers of T cell proliferation. They convert G0 phase in G1a phase, which is enough to reveal HIV infected T cells. In their work, Brooks et al., suggest that a novel form of AIDS therapy could be induced in HIV patients, which could be more effective than present combined HAART therapy. They suggest two-sided approach in their work. First is to reveal T cells which hide HIV, and second is to destroy it. They will try to destroy T cells by diphteria toxin associated with an antibody that can recognize just T cells infected with HIV. The proposed idea will be examined through experiments on mice and monkeys, which would reveal some new answers.
However, researchers will find some obstacles in their experiment, regarding IL-7. First of all, activity of IL-7 on cell cycle regulation is a reflection of sinergy with signalization mechanism between human SDF-1 (stromal cell derived factor 1/CXCL12) and CXCR4 receptor (Hernandez-Lopez et al., 2002). Furthermore, although IL-7 has no significant influence on T cell phenotype it has influence on up regulation of CXCR4 expression on bone marrow stem cells (CD34+). Receptor CXCR4 is known as a HIV coreceptor, and if expressed on CD34+ cells it could induce migration of HIV-X4 strain under that cell line. In such a condition, CD34+ will become new hosts for HIV, and as HIV has dual tropism, novel viral particles would have to attack more on the cells of monocyte-macrophage line in lack of T cells. As SDF-1 is natural ligand for CXCR4, its administration with IL-7 should be considered. If such experiment shows significant success as novel therapeutic pathway for HIV infection, it would be used just to reduce AIDS pathogenesis, but there should be no expectations that it could serve as complete cure for HIV infection.