Nicola Ferrari

Genetic variability of Haemonchus contortus (Nematoda: Trichostrongyloidea) in alpine ruminant host species

Genetic variability of the ovine parasite Haemonchus contortus from the Alpine area was investigated using mitochondrial DNA (nd4 gene), internal transcribed spacers 1 and 2 and microsatellites, in order to assess whether cross-transmission between domestic and wild ruminants occurs. The dataset was composed of 78 individual adult male H. contortus collected from chamois (Rupicapra r. rupicapra), roe deer (Capreolus capreolus), alpine ibex (Capra ibex ibex), domestic goat (Capra hircus) and sheep (Ovis aries) from different alpine areas. The data obtained show low host specificity and high genetic variation within H. contortus populations. The analyses indicate the presence of two mitochondrial haplotype clusters among host species and the absence of cryptic parasite species, confirming H. contortus as a generalist nematode and suggesting that parasite transmission between populations of domestic and wild ruminants normally occurs.

RUNX2 correlates with subtype-specific breast cancer in a human tissue microarray, and ectopic expression of Runx2 perturbs differentiation in the mouse mammary gland

RUNX2, a master regulator of osteogenesis, is oncogenic in the lymphoid lineage; however, little is known about its role in epithelial cancers. Upregulation of RUNX2 in cell lines correlates with increased invasiveness and the capacity to form osteolytic disease in models of breast and prostate cancer. However, most studies have analysed the effects of this gene in a limited number of cell lines and its role in primary breast cancer has not been resolved. Using a human tumour tissue microarray, we show that high RUNX2 expression is significantly associated with oestrogen receptor (ER)/progesterone receptor (PR)/HER2-negative breast cancers and that patients with high RUNX2 expression have a poorer survival rate than those with negative or low expression. We confirm RUNX2 as a gene that has a potentially important functional role in triple-negative breast cancer. To investigate the role of this gene in breast cancer, we made a transgenic model in which Runx2 is specifically expressed in murine mammary epithelium under the control of the mouse mammary tumour virus (MMTV) promoter. We show that ectopic Runx2 perturbs normal development in pubertal and lactating animals, delaying ductal elongation and inhibiting lobular alveolar differentiation. We also show that the Runx2 transgene elicits age-related, pre-neoplastic changes in the mammary epithelium of older transgenic animals, suggesting that elevated RUNX2 expression renders such tissue more susceptible to oncogenic changes and providing further evidence that this gene might have an important, context-dependent role in breast cancer.

Sarcoptic mange in wild carnivores and its co-occurrence with parasitic helminths in the Western Italian Alps

Between 2001 and 2004, 229 foxes, 36 stone martens and 48 badgers from the western Italian Alps were examined for sarcoptic mange and for gastrointestinal helminths to investigate their prevalence and geographical distribution and to point out the existence of potential interactions among them. Sarcoptic mange was observed in 25.3±2.8% SE of foxes and in 5.6±3.8% SE of stone martens, while no badger was found infected. Helminths belonged to Cestoidea Cyclophillidea (3.0±1.1% SE), Nematoda Trichurida (Capillaria aerophila and Trichuris vulpis: 6.5±1.6% SE; Trichinella britovi: 3.0±1.1% SE), Ascaridida (12.2±2.2% SE) and Strongylida (6.9±1.7% SE). Sarcoptic mange infection and the presence of helminths proved to be associated, with mangy foxes showing significantly higher prevalence of both cestode and nematode (particularly Ascaridida) worms. Moreover, considering three clusters of parasites (S. scabiei, nematodes and cestodes), more foxes than expected hosted simultaneously 2 and 3 taxa. These evidences suggest the existence of some kind of interaction, whose modalities and implications are discussed in this paper.

RUNX2 in mammary gland development and breast cancer

Runx2 is best known as an essential factor in osteoblast differentiation and bone development but, like many other transcription factors involved in development, is known to operate over a much wider tissue range. Our understanding of these other aspects of Runx2 function is still at a relatively early stage and the importance of its role in cell fate decisions and lineage maintenance in non‐osseous tissues is only beginning to emerge. One such tissue is the mammary gland, where Runx2 is known to be expressed and participate in the regulation of mammary specific genes. Furthermore, differential and temporal expression of this gene is observed during mammary epithelial differentiation in vivo, strongly indicative of an important functional role. Although the precise nature of that role remains elusive, preliminary evidence hints at possible involvement in the regulation of mammary stem and/or progenitor cells. As with many genes important in regulating cell fate, RUNX2 has also been linked to metastatic cancer where in some established breast cell lines, retention of expression is associated with a more invasive phenotype. More recently, expression analysis has been extended to primary breast cancers where high levels of RUNX2 align with a specific subtype of the disease. That RUNX2 expression correlates with the so called “Triple Negative” subtype is particularly interesting given the known cross talk between Runx2 and estrogen receptor signaling pathways. This review summaries our current understanding of Runx2 in mammary gland development and cancer, and postulates a role that may link both these processes. J. Cell. Physiol. 228: 1137–1142, 2013.

Expression of RUNX1 correlates with poor patient prognosis in triple negative breast cancer.

Abstract The RUNX1 transcription factor is widely recognised for its tumour suppressor effects in leukaemia. Recently a putative link to breast cancer has started to emerge, however the function of RUNX1 in breast cancer is still unknown. To investigate if RUNX1 expression was important to clinical outcome in primary breast tumours a tissue microarray (TMA) containing biopsies from 483 patients with primary operable invasive ductal breast cancer was stained by immunohistochemistry. RUNX1 was associated with progesterone receptor (PR)-positive tumours (P<0.05), more tumour CD4+(P<0.05) and CD8+(P<0.01) T-lymphocytic infiltrate, increased tumour CD138+plasma cell (P<0.01) and more CD68+macrophage infiltrate (P<0.001). RUNX1 expression did not influence outcome of oestrogen receptor (ER)-positive or HER2-positive disease, however on univariate analysis a high RUNX1 protein was significantly associated with poorer cancer-specific survival in patients with ER-negative (P<0.05) and with triple negative (TN) invasive breast cancer (P<0.05). Furthermore, multivariate Cox regression analysis of cancer-specific survival showed a trend towards significance in ER-negative patients (P<0.1) and was significant in triple negative patients (P<0.05). Of relevance, triple negative breast cancer currently lacks good biomarkers and patients with this subtype do not benefit from the option of targeted therapy unlike patients with ER-positive or HER2-positive disease. Using multivariate analysis RUNX1 was identified as an independent prognostic marker in the triple negative subgroup. Overall, our study identifies RUNX1 as a new prognostic indicator correlating with poor prognosis specifically in the triple negative subtype of human breast cancer.

Heligmosomoides polygyrus reduces infestation of Ixodes ricinus in free-living yellow-necked mice, Apodemus flavicollis.

Free-living animals are usually inhabited by a community of parasitic species that can interact with each other and alter both host susceptibility and parasite transmission. In this study we tested the prediction that an increase in the gastrointestinal nematode Heligmosomoides polygyrus would increase the infestation of the tick Ixodes ricinus, in free-living yellow-necked mice, Apodemus flavicollis. An extensive cross-sectional trapping survey identified a negative relationship between H. polygyrus and I. ricinus counter to the prediction. An experimental reduction of the nematode infection through anthelmintic treatment resulted in an increase in tick infestation, suggesting that this negative association was one of cause and effect. Host characteristics (breeding condition and age) and habitat variables also contributed to affect tick infestation. While these results were counter to the prediction, they still support the hypothesis that interactions between parasite species can shape parasite community dynamics in natural systems. Laboratory models may act differently from natural populations and the mechanism generating the negative association is discussed.

Toltrazuril and sulphonamide treatment against naturally Isospora suis infected suckling piglets: Is there an actual profit?

A study was carried out to assess the efficacy and the economic profit of prophylactic treatment against Isopsora suis with toltrazuril or with a sulfamethazine/trimethoprim combination in piglets from an intensive pig farm. Thirty-one litters were included in study. Eight litters were treated once with toltrazuril (20 mg/kg b.w.) at 3 days of age (Toltra group); 8 litters were treated with 2 ml/animal of a [corrected] sulphonamide combination (sodium sulfamethazine 250 [DOSAGE ERROR CORRECTED] mg and trimethoprim 50 [DOSAGE ERROR CORRECTED] mg/kg b.w.) for 3 consecutive days starting at 3 days of age (Sulfa group), and 15 litters were untreated (control group). Counts of oocyst per gram on pooled feces sampled from each litter were carried out on Days 7, 14, 21 and 28 and diarrhea was registered daily from pooled samples. Piglets were weighed on Days 1, 7 and 28 and mean weight gain (WG) and daily weight gain (DWG) were evaluated. The economic profit of treatment was evaluated comparing the WG of piglets of each treatment group from the day of birth to Day 28. On Days 14, 21 and 28, toltrazuril showed a better efficacy in controlling fecal oocyst output, diarrhea and weight gain compared with sulphamidic treatment (P<0.001). The budgeting analysis showed a return of economic benefit of euro 0.915 per toltrazuril-treated piglets and an additional cost of euro 1.155 per sulphonamide-treated piglets.

Effect of sexual segregation on host–parasite interaction: Model simulation for abomasal parasite dynamics in alpine ibex (Capra ibex)

We investigated whether sexual segregation might affect parasite transmission and host dynamics, hypothesising that if males are the more heavily infected sex and more responsible for the transmission of parasite infections, female avoidance of males and the space they occupy could reduce infection rates. A mathematical model, simulating the interaction between abomasal parasites and a hypothetical alpine ibex (Capraibex) host population composed of its two sexes, was developed to predict the effect of different degrees of sexual segregation on parasite intensity and on host abundance. The results showed that when females tended to be segregated from males, and males were distributed randomly across space, the impact of parasites was the lowest, resulting in the highest host abundance, with each sex having the lowest parasite intensity. The predicted condition that minimises the impact of parasites in our model was the one closest to that observed in nature where females actively seek out the more segregated sites while males are less selective in their ranging behaviour. The overlapping of field observation with the predicted optimal strategy lends support to our idea that there might be a connection between parasite transmission and sexual segregation. Our simulations provide the biological boundaries of host-parasite interaction needed to determine a parasite-mediated effect on sexual segregation and a formalised null hypothesis against which to test future field experiments.

Ljungan Virus and an Adenovirus in Italian Squirrel Populations

Abstract We report Ljungan virus infection in Eurasian red squirrels (Sciurus vulgaris) for the first time, and extend the known distribution of adenoviruses in both native red squirrels and alien gray squirrels (Sciurus carolinensis) to southern Europe.

Intestinal helminth communities of the red fox (Vulpes vulpes L.) in the Italian Alps

The study analyses the intestinal helminth communities found in 645 red foxes of alpine populations from five areas of Northern Italy. In particular, the aim was to evaluate the contribution of both environmental variability and the structure of fox population (extrinsic and intrinsic factors, respectively) in shaping the structure and composition of the intestinal helminth communities. To identify the influence of the characteristics of the host (i.e. age and sex) together with extrinsic factors (year, site, season, and altitude of collection) on number of species, total load per fox, prevalence and abundance of each parasite species, general linear models were performed. Fifteen helminth species have been detected in the intestine of 545 infected animals (84.5%) with a total of 17,144 parasites collected. The analysis of factors influencing both prevalence and abundance of infection of the parasite species revealed the preponderance of extrinsic factors on intrinsic ones. In particular, geographical areas influenced prevalence and abundance of every parasite species, showing high spatial variability. The lower influence of host factors may suggest that, in this case, host dynamics play a trivial role with respect to spatial variability in determining parasite abundance. These results pointed out high prevalence of intestinal helminth infections in the Italian Alpine fox, confirmed the typical composition of parasite fauna within fox populations, underlined local differences in the structure and composition of the helminth communities. Moreover, this study highlights the major role of extrinsic factors vs intrinsic ones.