Initial results of QuantiFERON-TB Gold testing in patients with uveitis.

PURPOSE: To describe the use of the second-generation QuantiFERON-TB Gold (QFT-G) test in a series of patients in an ophthalmic practice. METHODS: The charts of all patients who had QFT-G tests ordered by Mayo Clinic ophthalmologists in the past 3 years were reviewed. RESULTS: A total of 27 QFT-G tests were ordered. Thirteen (48%) tests were negative, six (22%) were indeterminate, two (7%) tests were re-ordered after a lab accident or an improper cancellation, four (15%) were positive and represented infection, and two (7%) were positive but negative when re-tested. Of the four truly positive cases, three were treated for tuberculosis (TB): one had tuberculous iritis, one had retinal vasculitis and haemorrhage, and one had asymptomatic TB but was on immunosuppressive therapy. The fourth patient had previously been treated for latent infection. CONCLUSIONS: In a series of selected patients with uveitis, the QFT-G test was able to detect TB infection in 15% of the patients, though it does not differentiate between active and latent TB infection. QFT-G should be considered in place of purified protein derivative testing in those with uveitis that have had prior BCG vaccination and in immunocompromised patients. Patients with a positive QFT-G, but who have little risk for TB infection and a negative systemic work-up, should be re-tested.

Stable transformation and direct regeneration in Coffea canephora P ex. Fr. by Agrobacterium rhizogenes mediated transformation without hairy-root phenotype.

A system for genetic transformation of Coffea canephora by co-cultivation with Agrobacterium rhizogenes harbouring a binary vector has been developed. The objective of the present study was the genetic transformation and direct regeneration of transformants through secondary embryos bypassing an intervening hairy root stage. Transformants were obtained with a transformation efficiency up to 3% depending on the medium adjuvant used. A. rhizogenes strain A4 harbouring plasmid pCAMBIA 1301 with an intron uidA reporter and hygromycin phosphotransferase (hptII) marker gene was used for sonication-assisted transformation of Coffea canephora. The use of hygromycin in the secondary embryo induction medium allowed the selection of transgenic secondary embryos having Ri T-DNA along with the T-DNA from the pCAMBIA 1301 binary vector. In addition transgenic secondary embryos devoid of Ri-T-DNA but with stable integration of the T-DNA from the binary vector were obtained. The putative transformants were positive for the expression of the uidA gene. PCR and Southern blot analysis confirmed the independent, transgenic nature of the analysed plants and indicated single and multiple locus integrations. The study clearly demonstrates that A. rhizogenes can be used for delivering transgenes into tree species like Coffea using binary vectors with Agrobacterium tumefaciens T-DNA borders.