Severe erosive gingivostomatitis in a patient treated by vedolizumab.

Vedolizumab is a humanized monoclonal antibody that binds to the human a4ß7 integrin and is approved for use in inflammatory bowel diseases. We describe a patient with severe, refractory erosive gingivostomatitis, which appeared a few days after the first dose of vedolizumab and resolved after discontinuation of the drug. We believe the gingivostomatitis to be a direct side effect of vedolizumab, rather than an extraintestinal manifestation of the underlying inflammatory bowel diseases. The clinicians need to be aware of this adverse event, which could be mistakenly considered as an extraintestinal manifestation of inflammatory bowel diseases.

Resistance to tospoviruses in Nicotiana benthamiana transformed with the N gene of tomato spotted wilt virus: correlation between transgene expression and protection in primary transformants.

Nicotiana benthamiana was transformed with the nucleoprotein (N) gene of an Italian isolate of tomato spotted wilt virus (TSWV). Forty-five T1 primary transformant lines were analyzed for the expression of N protein and for resistance to TSWV and three other tospoviruses: impatiens necrotic spot virus (INSV), groundnut bud necrosis virus (GBNV), and groundnut ringspot virus (GRSV). Thirteen of these lines were further characterized. Resistance to all TSWV isolates tested was found in two lines. The expression of the transgene (N mRNA) was lower in these resistant lines than in any of the susceptible lines, and the transgene N protein was either absent or present below detectable levels. These lines were susceptible to the other tospoviruses tested, but they developed symptoms milder than controls when inoculated with GRSV. Some of the lines producing high levels of N protein showed delays (of 2-3 weeks) in symptom expression with at least one of the TSWV isolates tested and symptom delay or attenuation with INSV or GRSV (or both). From our results it appears that high expression of TSWV N protein retards, in some cases, disease development by TSWV and INSV. In contrast, the lack of detectable expression of the transgenic N protein, accompanied by limited production of N transcripts, conferred TSWV-specific resistance.