Anti-RPL7 (aa 19-68) polyclonal antibody

BACKGROUND: Intestinal bacteria have long been implicated in colorectal cancer pathology, and many reports point to a close linkage between Streptococcus bovis biotype I (recently renamed Streptococcus gallolyticus) infections and tumors of the human colon. This work aims to investigate the humoral immune response to this bacterium during different stages of colorectal cancer. METHODS: The presence of serum antibodies against S. bovis antigen RpL7/L12, previously assigned as a potential diagnostic antigen, was evaluated in Dutch (n=209) and American (n=112) populations using a newly developed enzyme-linked immunosorbent assay. RESULTS: The analyses consistently showed that an immune response against this bacterial antigen was increased in polyp patients and stage I/II colorectal cancer patients as compared with asymptomatic individuals. This was not paralleled by increased antibody production to endotoxin, an intrinsic cell wall component of the majority of intestinal bacteria, which implies that the humoral immune response against RpL7/L12 is not a general phenomenon induced by the loss of colonic barrier function. Notably, increased anti-RpL7/L12 levels were not or were only mildly detected in late stage colorectal cancer patients having lymph node or distant metastasis. CONCLUSIONS: These findings are indicative of an increased exposure to antigen RpL7/L12 during early stages of colon carcinogenesis and suggest that intestinal bacteria such as S. bovis constitute a risk factor for the progression of premalignant lesions into early stage carcinomas. Clearly, the current findings emphasize the necessity for further studies on the possible etiologic relationship between intestinal bacteria and human colorectal cancer. Cancer 2010;116:4014-22. (C) 2010 American Cancer Society

Potyvirus infection has been reported to cause an increase in the mRNA transcripts of many plant ribosomal proteins (r-proteins). In this Study, increased expression of r-protein mRNA transcripts was determined to occur in Nicotiana benthamiana during infection by potyviruses as well as a tobamovirus demonstrating that this response is not unique to potyviruses. Five r-protein genes, RPS6, RPL19, RPL13, RPL7, and RPS2. were silenced in N. benthamiana to test their roles in viral infection. The accumulation of both Turnip mosaic virus (TuMV), a potyvirus, and Tobacco mosaic virus (TMV), a tobamovirus, was dependent on RPL19, RPL13, RPL7, and RPS2. However, TMV was able to accumulate in RPS6-silenced plants while accumulation of TuMV and Tomato bushy stunt virus (TBSV) was abolished. These results demonstrate that cap-independent TuMV and TBSV require RPS6 for their accumulation, whereas accumulation of TMV is independent of RPS6. (C) 2009 Elsevier Inc. All rights reserved.