Bovine ocular squamous cell carcinoma (OSCC) is the second most common cause of rejection due to neoplasia in slaughterhouses on Sao Miguel Island, Azores, and accounts for significant economic losses. To obtain a better insight into the genesis and neoplastic transformation process of bovine OSCC, abnormal protein expression and proliferation index were assessed by the immunohistochemical evaluation of p53 and Ki67, respectively. OSCC samples were collected from 15 bovines and were classified histologically according to the degree of differentiation into three categories: poorly, moderately, and well differentiated. Immunohis-tochemistry using polyclonal anti-human p53 antibody and polyclonal anti-human Ki67 antibody was performed. Ten of 15 tumors tested were immunoreactive for p53. Twelve tumors demonstrated Ki67 expression. As in human squamous cell carcinoma, p53 overexpression is frequent in bovine OSCC, providing support for a possible role of the protein in the pathogenesis of this neoplasia. No correlation between the percentage of p53 stained nuclei and the degree of differentiation was observed, although different patterns of staining were seen according to the degree of keratinization of the tumor cells. With the exception of the moderately differentiated OSCC group, Ki67 index showed significant correlation with the histologic pattern, increased proliferation being found in poorly differentiated OSCC ( P = 0.013).

In order to investigate the effect of a dietary amino acid mixture supplementation in lipopolysaccharide (LPS)-challenged weaned piglets, twenty-seven 28-day-old (8.2 ± 1.0 kg) newly weaned piglets were randomly allocated to one of three experimental treatments for five weeks. Diet 1: a CTRL treatment. Diet 2: an LPS treatment, where piglets were intraperitoneally administered LPS (25 μg/kg) on day 7. Diet 3: an LPS+MIX treatment, where piglets were intraperitoneally administered LPS on day 7 and fed a diet supplemented with a mixture of 0.3% of arginine, branched-chain amino acids (leucine, valine, and isoleucine), and cystine (MIX). Blood samples were drawn on day 10 and day 35, and serum was analysed for selected chemical parameters and proteomics. The LPS and LPS+MIX groups exhibited an increase in haptoglobin concentrations on day 10. The LPS group showed an increased cortisol concentration, while this concentration was reduced in the LPS+MIX group compared to the control group. Similarly, the LPS+MIX group showed a decreased haptoglobin concentration on day 35 compared to the two other groups. Immunoglobulin concentrations were affected by treatments. Indeed, on day 10, the concentrations of IgG and IgM were decreased by the LPS challenge, as illustrated by the lower concentrations of these two immunoglobulins in the LPS group compared to the control group. In addition, the supplementation with the amino acid mixture in the LPS+MIX further decreased IgG and increased IgM concentrations compared to the LPS group. Although a proteomics approach did not reveal important alterations in the protein profile in response to treatments, LPS-challenged piglets had an increase in proteins linked to the immune response, when compared to piglets supplemented with the amino acid mixture. Overall, data indicate that LPS-challenged piglets supplemented with this amino acid mixture are more protected against the detrimental effects of LPS.

In invasive malignancies, Dll4/Notch signaling inhibition enhances non-functional vessel proliferation and limits tumor growth by reducing its blood perfusion. To assess the effects of targeted Dll4 allelic deletion in the incipient stages of tumor pathogenesis, we chemically induced skin papillomas in wild-type and Dll4+/− littermates, and compared tumor growth, their histological features, vascularization and the expression of angiogenesis-related molecules. We observed that Dll4 down-regulation promotes productive angiogenesis, although with less mature vessels, in chemically-induced pre-cancerous skin papillomas stimulating their growth. The increase in endothelial activation was associated with an increase in the VEGFR2 to VEGFR1 ratio, which neutralized the tumor-suppressive effect of VEGFR-targeting sorafenib. Thus, in early papillomas, lower levels of Dll4 increase vascularization through raised VEGFR2 levels, enhancing sensitivity to endogenous levels of VEGF, promoting functional angiogenesis and tumor growth. Tumor promoting effect of low-dosage inhibition needs to be considered when implementing Dll4 targeting therapies.

Cryptosporidium parvum is an intracellular parasite causing enteritis which can become life-threatening in immunocompromised host. Immunoregulatory T cells play a central role in the regulatory network of the host. Here, we proposed to characterize the populations of immune cells during infection and reinfection with C. parvum. Four-week-old BALB/C mice were inoculated with oocysts of C. parvum at days 0 and 22. Fecal and blood samples, spleens, and small intestines were collected for analysis. Peripheral blood and spleen cell populations were characterized by flow cytometry. After infection (days 0 to 21), mice presented higher values of neutrophils, eosinophils, NK cells and CD4+CD25high T cells in peripheral blood. After reinfection, this upward trend continued in the following days for all four populations in infected mice. At day 35, infected mice presented similar values to the control group, except for CD4+CD25high T cells, which remained higher in infected mice. A possible correlation between alterations in blood and spleen cell populations was also studied, but no consistent association could be established. Small intestine sections were screened for intracellular stages of the parasite but no evidence of pathology was observed. Here, we report information which may be important for the understanding of the specific cell-mediated response in immunocompetent mice to C. parvum infection. Although some questions remain unanswered and complementary studies are needed, our results are expected to contribute to a better understanding of innate and Treg cells role in the clearance process of this parasite.