Nicotiana tabacum 46-8 cultivar displays an incompatible interaction with race 0 of Phytophthora parasitica var. nicotianae (Ppn), a fungal pathogen of most tobacco cultivars. At the plant level, incompatibility is characterized by the induction of lipoxygenase (LOX, EC ‫؍‬ 1.13.11.12) activity and localized hypersensitive cell death before defense gene activation. To evaluate the involvement of LOX in the onset of plant defense, tobacco 46-8 plants were genetically engineered using full-length or partial-length antisense (AS) tobacco LOX cDNA constructs. AS expression strongly reduced elicitor-and pathogen-induced LOX activity. Eight independent AS-LOX lines were selected and assayed for their response to Ppn. After root or stem inoculation with race 0, all AS-LOX lines but one displayed a compatible phenotype whereas control transformed plants, not containing the AS-LOX cassette, showed the typical incompatible reaction. The presence of the fungus in transgenic lines was demonstrated by PCR amplification of a Ppn-specific genomic sequence. A linear relationship was found between the extent of LOX suppression and the size of the lesion caused by the fungus. The AS-LOX plants also showed enhanced susceptibility toward the compatible fungus Rhizoctonia solani. The results demonstrate the strong involvement of LOX in the establishment of incompatibility in plant-microorganism interactions, consistent with its role in the defense of host plants.

Interleukin-7 (IL-7), the principal cytokine implicated in thymopoiesis and peripheral T-cell homeostasis, is presently under evaluation in human diseases characterized by persistent lymphopenia. Unexpectedly, before the eventual IL-7-driven T-cell expansion, all treated patients showed a profound T-cell depletion 24 hours after injection. The current study uses the rhesus macaque model to investigate the mechanisms involved in this IL-7-induced T-cell depletion. We identify a new critical function of IL-7 that induces massive and rapid T-cell migration from the blood into various organs, including lymph nodes, parts of the intestine, and the skin. This homing process was initiated after the induction of chemokine receptor expression by circulating T cells and the production of corresponding chemokines in target organs. Finally, we demonstrate that the IL-7-induced cell cycling is initiated within these organs before T cells migrate back into the bloodstream, indicating that T-cell homing is required for in vivo IL-7 function. (Blood. 2009;114:816-825)

Regeneration of indica rice varieties remains a limiting factor for researchers undertaking rice Iransformation experiments. As reported for japonica rice and other crops, partial desiccation of indica rice calli dramatically promotes organogenesis and leads to high regeneration ability. We are now able to obtain 66.5%, 61.1% and 73.7% of calli that regenerate plants for the indica varieties TN1, IR72 and IR64 whereas in non desiccated controls only 30.0%, 15.5% and 18.7% of calli regenerated, respectively. Plants obtained were phenotypically normal and 50% were highly fertile. Partial desiccation is a reliable and simple method for improving indica rice regeneration. It also shortens the time of in vitro culture.

Interferon-␣ (IFN-␣)-based therapy ispresently the standard treatment for hepatitis C virus (HCV)-infected patients. Despite good effectiveness, this cytokine is associated with major side effects, including significant lymphopenia, that limits its use for HIV/HCV-coinfected patients. Interleukin-7 (IL-7) has recently shown therapeutic potential and safety in several clinical trials designed to demonstrate T-cell restoration in immunodeficient patients. The purpose of this study was to evaluate, in simian immunodeficiency virus-infected rhesus macaques, the relevance of IL-7 therapy as a means to overcoming IFN-␣-induced lymphopenia. We showed that low-dose IFN-␣ treatment induced strong lymphopenia in chronically infected monkeys. In contrast, high-dose IFN-␣ treatment stimulated IL-7 production, leading to increased circulating T-cell counts. Moreover, IL-7 therapy more than abrogated the lymphopenic effect of low-dose IFN-␣. Indeed, the association of both cytokines resulted in increased circulating T-cell IntroductionCoinfection with HIV and hepatitis C virus (HCV) has become an increasingly common occurrence, with an estimated 25% to 30% of HIV ϩ patients also being HCV ϩ . 1 As a consequence, since the appearance of highly active antiretroviral therapy (HAART), chronic liver disease has become one of the most common causes of morbidity and mortality in HIV patients. 2,3 Although the effectiveness of standard HCV treatment, based on interferon-␣ (IFN-␣) injections, is known to decrease the longer a patient has been infected with the virus, HCV patients are not systematically put under treatment. Rather, initiation of treatment depends on the state of the patient's liver (fibrosis markers, serum aminotransferases, HCV RNA, hepatitis B virus status) and other parameters, which in turn are used to determine whether the potential benefits of therapy outweigh the risks of treatment-related toxicity. 4 For HIV-HCV-coinfected patients, some of these parameters are: the assessment of HIV disease status, such as current and past opportunistic infections, HIV-associated malignancies, CD4 count, HIV viral load, and details of HAART therapy, with CD4 count being one of the main criteria. Unfortunately, coinfected patients are poor responders to standard treatment as a sustained viral response occurs in only 27% to 40% of these patients, approximately half the rate seen in HCV-monoinfected patients. [5][6][7] The main reason for this difference can be attributed to exhaustion of the immune system. In addition, IFN-␣ treatment causes a leukopenia, including a decrease of lymphocyte numbers and thus of CD4 count, often leading to premature treatment interruption. [8][9][10][11][12] Therefore, to enhance the efficiency of anti-HVC therapy in coinfected patients, it is critically important to develop an alternative treatment that limits the lymphopenic effect of IFN-␣ therapy.Interleukin 7 (IL-7), a cytokine that promotes precursor B-and T-cell maturation [13][14][15] and supports peripheral T-cell homeostasis, [16][17][18...

The proximal region of the high-molecular-weight glutenin promoter of the Dx5 gene (PrHMWG-Dx5) carries an atypical bifactorial endosperm box containing two cis-acting elements, namely a G-box like motif followed by a prolamin-box motif (Pb1). Transient expression assays in maize endosperm indicate that a promoter fragment containing at least the G-box like element is necessary and sufficient for maximal expression of the HMWG-Dx5 promoter. In transformed maize, we have shown that a 89 bp sequence bearing the bifactorial endosperm box behaves like a functional cis-acting unit. Its repetition in tandem confers a strong specific additive effect specifically in endosperm tissue. In contrast, the fusion of the activation sequences 1 (as-1) and 2 (as-2) of the cauliflower mosaic virus (CaMV) 35S promoter with HMWG-Dx5 derived promoter sequences deregulates its activity in transformed maize. By gel mobility shift assays we have demonstrated that the G-box like motif may alternatively bind two protein groups which have the same DNA-binding affinities as the transcription factors of either the Opaque2 (O2) family and/or the ASF-1 family.

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The aim of the present work was to develop a simple high-resolution CZE method for glycoform profiling and quality assessment of recombinant human interleukin-7 (rhIL-7) produced in Chinese hamster ovary cells. Classical and isoelectric buffers and several monoamines used as alkaline component of BGE at very low concentration have been investigated in order to optimize the resolution. The best separation was achieved using a fused-silica capillary and a buffer composed of 25 mM citrate/triethanolamine at pH 2.6. Under these acidic conditions, triethanolamine was able to reverse EOF favorably and to limit rhIL-7 adsorption. This method allowed the separation of four groups of peaks ranging from low to high-sialylated glycoforms. An extensive study on inter-run rinsing procedures has been conducted. Rinsing with 50 mM SDS was retained to achieve the optimal repeatability. Excellent intermediate precision was obtained for migration time (RSD < 0.6%), while RSD for intraday studies were only less than 2.9%. Satisfactory inter and intraday repeatabilities were also observed for relative peak area. We finally demonstrated that reliable information could be obtained to address comparability studies and demonstrate batch-to-batch consistency of biomanufactured rhIL-7.

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