Multiple cytotoxic factors involved in IL-21 enhanced antitumor function of CIK cells signaled through STAT-3 and STAT5b pathways.

BACKGROUND/OBJECTIVES: Maintenance of cellular function in culture is vital for transfer and development following adoptive immunotherapy. Dual properties of IL-21 in activating T cells and reducing activation induced cell death led us to explore the mechanism of action of IL-21 enhanced proliferation and cytotoxic potential of CIK cells. METHOD: CIK cells cultured from PBMCs of healthy subjects were stimulated with IL-21 and cellular viability and cytotoxicity to K562 cells were measured. To elucidate the mechanism of action of IL-21, mRNA expression of cytotoxic factors was assessed by RT-PCR and protein expression of significantly important cytotoxic factors and cytokine secretion were determined through flow cytometry and ELISA. Western blotting was performed to check the involvement of the JAK/STAT pathway following stimulation. RESULTS: We found that IL-21 did not enhance in vitro proliferation of CIK cells, but did increase the number of cells expressing the CD3+/ CD56+ phenotype. Cytotoxic potential was increased with corresponding increase in perforin (0.9831±0.1265 to 0.7592±0.1457), granzyme B (0.4084±0.1589 to 0.7319±0.1639) and FasL (0.4015±0.2842 to 0.7381±0.2568). Interferon gamma and TNF-alpha were noted to increase (25.8±6.1 ng/L to 56.0±2.3 ng/L; and 5.64±0.61 µg/L to 15.14±0.93 µg/L, respectively) while no significant differences were observed in the expression of granzyme A, TNF-alpha and NKG2D, and NKG2D. We further affirmed that IL-21 signals through the STAT-3 and STAT- 5b signaling pathway in the CIK cell pool. CONCLUSION: IL-21 enhances cytotoxic potential of CIK cells through increasing expression of perforin, granzyme B, IFN-gamma and TNF-alpha. The effect is brought about by the activation of STAT-3 and STAT-5b proteins.

A non-coding plastid DNA phylogeny of Asian Begonia (Begoniaceae): evidence for morphological homoplasy and sectional polyphyly.

Maximum likelihood and Bayesian analyses of non-coding plastid DNA sequence data based on a broad sampling of all major Asian Begonia sections (ndhA intron, ndhF-rpl32 spacer, rpl32-trnL spacer, 3977 aligned characters, 84 species) were used to reconstruct the phylogeny of Asian Begonia and to test the monophyly of major Asian Begonia sections. Ovary and fruit characters which are crucial in current sectional circumscriptions were mapped on the phylogeny to assess their utility in infrageneric classifications. The results indicate that the strong systematic emphasis placed on single, homoplasious characters such as undivided placenta lamellae (section Reichenheimia) and fleshy pericarps (section Sphenanthera), and the recognition of sections primarily based on a suite of plesiomorphic characters including three-locular ovaries with axillary, bilamellate placentae and dry, dehiscent pericarps (section Diploclinium), has resulted in the circumscription of several polyphyletic sections. Moreover, sections Platycentrum and Petermannia were recovered as paraphyletic. Because of the homoplasy of systematically important characters, current classifications have a certain diagnostic, but only poor predictive value. The presented phylogeny provides for the first time a reasonably resolved and supported phylogenetic framework for Asian Begonia which has the power to inform future taxonomic, biogeographic and evolutionary studies.

Costs of patients hospitalized for multidrug-resistant tuberculosis.

SETTING: From 1993 through 1998, 1846 cases of multidrug-resistant tuberculosis (MDR-TB) were reported in the United States. Costs associated with MDR-TB are likely to be much higher than for drug-susceptible tuberculosis due to longer hospitalization, longer treatment with more expensive and toxic medications, greater productivity losses, and higher mortality. OBJECTIVE: To measure the societal costs of patients hospitalized for MDR-TB. DESIGN: We detailed in-patient costs for 13 multidrug-resistant patients enrolled in a national study. We estimated costs for physician care, out-patient treatment, and productivity losses for survivors and for deceased patients. RESULTS: In-patient costs averaged US$25,853 per person and $1036 per person-day of hospitalization. Outpatient costs per person ranged from $5744 to $41,821 (average $19028, or $44 a day). Direct medical costs averaged $44,881; indirect costs for those who survived averaged $32,964, and indirect costs for those who died averaged $686,381 per person. Total costs per person ranged from $28,217 to $181492 (average $89,594) for those who survived, and from $509490 to $1278066 (average $717555) for those who died. CONCLUSION: The societal costs of MDR-TB varied, mostly because of length of therapy (including in-patient), and deaths during treatment.