Human cytokine-induced killer cells specifically infiltrated and retarded the growth of the inoculated human cholangiocarcinoma cells in SCID mice.

Cytokine-induced killer (CIK) cells were examined for safety and efficacy for cholangiocarcinoma treatment. Several conditions of human CIK cells were examined using ex vivo cytotoxic assay and SCID mice pre-inoculated with cholangiocarcinoma cells. We monitored the ex vivo cytotoxicity, tumor sizes and immunohistochemistry. Optimal tumor suppression was observed when CIK cells were pre-exposed to dendritic cells (DCs). Unexpectedly, pulsing of tumor RNA to DCs rendered the co-culturing CIK cells ineffective and raised the proportion of CD4(+)CD25(+) subset. The use of CD3(+)CD56(+) subset instead of the whole population of CIK cells for the co-culture with RNA-pulsed DCs restored the efficacy. Tumor-infiltrating human CD3(+) cells were observed from day 2 - 14. The CD3(+)CD56(+) cells are logical candidates for clinical trial while the DC-co-cultured CIK cells produced similar efficacy and more feasible for clinical application. The RNA pulsation of DCs up-regulated the regulatory subset of CIK cells and abrogated the anti-tumor efficacy.

Ultrastructural changes of pancreatic islets microcirculation in nonobese diabetic (NOD) mice.

The objective of this study was to investigate the ultrastructural changes of vascular pancreatic islets using a transmission electron microscopic technique. The major ultrastructural changes of microvessel in NOD mice are indicated by the swelling and vacuolization of the endothelial cell. Swollen cells are the first noticeable lesion of the cell response in reversible degeneration that is caused by the failure of homeostatic control. Loss in endothelial cell homeostasis is primarily a marker of endothelial dysfunction that plays a key role in the pathogenesis of diabetic vascular disease by losing the control of vascular tone. Diabetes also associates with an increased generation of oxygen-derived free radicals that may impair vasodilatation through the inactivation of vasodilators. In conclusion, consistent with a hypothesis that loss of the modulatory role of the endothelium may be a critical and initiating factor in the development of diabetic vascular disease, the ultrastructural changes in this study may indicate the first sign of endothelial dysfunction. This dysfunction correlates to the relationship between diabetes and reversible lesions of vessels in NOD mice, making for a better understanding of the pathophysiology of diabetic vascular disease to set the stage for further investigation to restore endothelial dysfunction in diabetes.

Specific immune response and pathological findings in BALB/c mice inoculated with recombinant BCG expressing HIV-1 antigen.

Recombinant BCGs (rBCGs) containing extrachromosomal plasmids with different HIV-1 insert sequences: nef, env (V3J1 and E9Q), gag p17 or whole gag p55 were evaluated for their immunogenicity, safety and persistent infection in BALB/c mice. Animal injected with, rBCG-plJKV3J1, rBCG-pSO gag p17 or rBCG-pSO gag p55 could elicit lymphocyte proliferation as tested by specific HIV-1 peptides or protein antigen. Inoculation with various concentration of rBCG-pSO gag p55 generated satisfactory specific lymphocyte proliferation in dose escalation trials. The rBCG-pSO gag p55 recovered from spleen tissues at different time interval post-inoculation could express the HIV protein as determined by ELISA p24 antigen detection kit. This result indicated that the extrachromosomal plasmid was stable and capable to express Gag protein. It was also demonstrated that rBCGs did not cause serious pathological change in the inoculated animals. The present study suggested the role of BCG as a potential vehicle for using in HIV vaccine development.

Chronic toxicity study of Portulaca grandiflora Hook.

We investigated the toxic effects of Portulaca grandiflora aqueous extract given to male and female Wistar rats for 6 months. The rats were divided into five groups of each sex that were control groups, three experimental groups and recovery groups. The control groups received 5 ml of distilled water/kg per day. The experimental groups were orally given the water extract of Portulaca grandiflora at doses of 10, 100 and 1000 mg/kg per day. The recovery groups received 1000 mg/kg per day for 6 months and were continued husbandry without giving the extract for further 14 days. Changes in the body weights, actual and relative organ weights were not significantly demonstrated in all groups throughout the study. No significant alteration in hematological, biochemical and histopathological parameters was observed in all female groups given the extract. It was found that any significant changes in hematological and biochemical parameters in the male rats at the doses of 100 and 1000 mg/kg per day were not dose-related. In addition, no histopathological lesions were observed in the male animals. Our results suggested that the water extract of Portulaca grandiflora at the doses given in the study did not induce any detrimental effects in the rats.

Effect of vaccination with refined components of the organism on infection of mice with Mycobacterium leprae.

Only native products of Mycobacterium leprae, whether cell wall, cytosol, or membrane derived, can confer protective immunity against challenge in the mouse footpad. Previously, recombinant proteins were shown to be ineffective. The cell wall skeleton-the mycolyl-arabinogalactan-peptidoglycan complex-devoid of proteins is not protective.