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Background: Nerve Growth Factor (NGF) plays an important role in the reproductive system through its receptor's interaction (p75NTR). This paper aims to analyze the impact of NGF p75NTR in epididymal and ejaculated rabbit semen during in vitro sperm storage. Methods: Semen samples from 10 adult rabbit bucks were collected four times (n = 40) and analyzed. NGF was quantified in seminal plasma, and the basal expression of p75NTR in sperm was established (time 0). Moreover, we evaluated p75NTR, the apoptotic rates, and the main sperm parameters, at times 2–4 and 6 h with or without the administration of exogenous NGF. Results: Based on the level of p75NTR, we defined the threshold value (25.6%), and sperm were divided into High (H) and Normal (N). During sperm storage, p75NTR of H samples significantly modulated some relevant sperm parameters. Specifically, comparing H samples with N ones, we observed a reduction in motility and non-capacitated cell number, together with an increased percentage of dead and apoptotic cells. Notably, the N group showed a reduction in dead and apoptotic cells after NGF treatment. Conversely, the NGF administration on H sperm did not change either the percentage of dead cells or the apoptotic rate. Conclusion: The concentration of p75NTR on ejaculated sperm modulates many semen outcomes (motility, apoptosis, viability) through NGF interaction affecting the senescence of sperm. [ABSTRACT FROM AUTHOR]

Despite promising immunotherapy strategies in human melanoma, there are few studies on the immune environment of canine melanocytic tumors. In humans, the activation of immunosuppressive cell subpopulations, such as regulatory T cells (Tregs) that express forkhead box protein P3 (FoxP3), the engagement of immunosuppressive surface receptors like cytotoxic T lymphocyte antigen (CTLA-4), and the secretion of molecules inhibiting lymphocyte activation, such as indoleamine-pyrrole 2,3-dioxygenase (IDO), are recognized as immunoescape mechanisms that allow tumor growth and progression. The aim of our study was to investigate the expression of these immunosuppression markers in canine melanocytic tumors and to postulate their possible role in melanoma biology and progression. Fifty-five formalin-fixed, paraffin-embedded canine melanocytic tumors (25 oral melanomas; 20 cutaneous melanomas; 10 cutaneous melanocytomas) were selected to investigate the expression of FoxP3, CTLA-4, and IDO by immunohistochemistry and RT-qPCR (real-time quantitative polymerase chain reaction). All of the tested markers showed high gene and protein expression in oral melanomas and were differently expressed in cutaneous melanomas when compared to their benign counterpart. IDO expression was associated with an increased hazard of death both in univariable and multivariable analyses (P <.05). FoxP3 protein expression >6.9 cells/HPF (high-power field) was an independent predictor of death (P <.05). CTLA-4 gene and protein expressions were associated with a worse prognosis, but only in the univariable analysis (P <.05). FoxP3, CTLA-4, and IDO likely play a role in canine melanoma immunoescape. Their expression, if supported by future studies, could represent a prognostic tool in canine melanoma and pave the way to future immunotherapeutic approaches in dogs. [ABSTRACT FROM AUTHOR]

The study of the immune response in several types of tumours has been rapidly increasing in recent years with the dual aim of understanding the interactions between neoplastic and immune cells and their importance in cancer pathogenesis and progression, as well as identifying targets for cancer immunotherapy. Despite being considered one of the most immunogenic tumour types, melanoma can progress in the presence of abundant lymphocytic infiltration, therefore suggesting that the immune response is not able to efficiently control tumour growth. The purpose of this study was to investigate whether the density, distribution and grade of tumour‐infiltrating lymphocytes (TILs) in 97 canine melanocytic tumours is associated with histologic indicators of malignancy and can be considered a prognostic factor in the dog. As a further step in the characterization of the immune response in melanocytic tumours, an immunohistochemical investigation was performed to evaluate the two main populations of TILs, T‐lymphocytes (CD3+) and B‐lymphocytes (CD20+). The results of our study show that TILs are present in a large proportion of canine melanocytic tumours, especially in oral melanomas, and that the infiltrate is usually mild. The quantity of CD20+ TILs was significantly associated with some histologic prognostic factors, such as the mitotic count, the cellular pleomorphism and the percentage of pigmented cells. Remarkably, a high infiltration of CD20+ TILs was associated with tumour‐related death, presence of metastasis/recurrence, shorter overall and disease‐free survival, increased hazard of death and of developing recurrence/metastasis, hence representing a potential new negative prognostic factor in canine melanocytic tumours. [ABSTRACT FROM AUTHOR]

Feline Immunodeficiency Virus (FIV) infection represents a viral immunosuppressive condition that predominantly affects the immune system, having no curative therapeutic options. The present research focused on the biological and physical effect of the use of poly-specific avian immunoglobulin Y (IgY) on some immune molecules of FIV infected cats, especially on gamma-globulins and white blood cells, as well as on how this therapy can amend or improve the quality of life of infected cats. The polyspecific avian immunoglobulin Y was used to treat two groups of feline patients: 10 patients infected with FIV and 10 patients free of the disease. The patients were monitored via blood samples collected on days 0, 20 and 40. The samples were used for testing the biochemical profile, CBC, WBC and the plasma concentration of 10 cytokines: Fas, IFNγ, IL-1β, IL-2, IL-4, IL-5, IL-8, IL-10, IL-12p40 and RANTES. The study also attempted to establish the eventual side effects associated with the suppressed immune system of FIV infected cats. [ABSTRACT FROM AUTHOR]

Human melanoma is one of the deadliest forms of cancer, with poor prognosis and high resistance to chemotherapy and radiotherapy. The discovery of immunosuppressive mechanisms in the human melanoma microenvironment led to the use of new prognostic markers and to the development of immunotherapies targeting immune checkpoint molecules. Immunoescape mechanisms in canine melanoma have not yet been investigated, and no such immunotherapy has been tested. The aim of this study was to provide preliminary data on the expression of transcription factor forkhead box protein P3 (FoxP3) and indoleamine 2,3-dioxygenase (IDO) in primary canine melanocytic tumors and to investigate their prognostic role. Formalin-fixed, paraffin-embedded samples from 74 canine melanocytic tumors (26 oral melanomas, 23 cutaneous melanomas, and 25 cutaneous melanocytomas) were retrospectively evaluated by immunohistochemistry to explore the expression of FoxP3 and IDO. An increased risk of death due to melanoma was associated with a higher number of FoxP3+ cells per high-power field (FoxP3+/HPF), a higher percentage of CD3+ cells that were also FoxP3+ infiltrating and surrounding the tumor (%FoxP3), and a higher number of IDO+ cells/HPF (IDO+/HPF). A prognostic value for FoxP3 and IDO is suggested by our study, with optimal cutoffs of 14.7 FoxP3+ cells/HPF, 6.1 IDO+ cells/HPF, and 12.5% FoxP3+ cells. Both markers were also associated with tumor type. Multivariable analysis identified IDO+/HPF (P < .001) as an independent prognostic marker. Even though stratification by diagnosis caused a loss of significance, results from the present study suggest a prognostic role for IDO and FoxP3, possibly related to the establishment of an immunosuppressive microenvironment. [ABSTRACT FROM AUTHOR]

Breslow thickness and Clark level are prognostic factors for human cutaneous melanomas. Breslow thickness is measured with an ocular micrometer from the top of the granular layer of the epidermis to the deepest invasive cell across the broad base of the tumor, while Clark level is based on the anatomical level of invasion through the layers of the dermis. Because of the anatomical differences between humans and dogs, we evaluated the tumor thickness and a modified Clark level in 77 canine primary cutaneous melanocytic tumors. Tumor thickness (using both a traditional and a more convenient system) and modified Clark level were measured and associated with histological diagnosis and clinical outcome. Tumor thickness was a prognostic factor, being greater in animals with shorter overall survival and disease-free time. Cutoffs of 0.95 cm and 0.75 cm defined a higher hazard for an unfavorable outcome and to develop recurrence/metastasis, respectively. Because of an excellent agreement between the 2 methods, it was concluded that tumor thickness could be measured with a ruler when an ocular micrometer is not available. Modified Clark level was not found to be relevant for prognosis. However, we suggest that both tumor thickness and a modified Clark level can be valid additional parameters when histological diagnosis is uncertain. Further studies, including a wider sample population, would be worthwhile to confirm the prognostic significance of these 2 parameters. [ABSTRACT FROM AUTHOR]

Inflammation of the uterus and oviduct is associated with reduced reproductive performance in humans and domestic animals. Toll-like receptors are expressed in various immune and non-immune cells and play a crucial role in innate immunity. Toll-like receptor – 4 (TLR4) can detect lipopolysaccharide (LPS) from Gram-negative bacteria leading to the secretion of pro-inflammatory cytokines, chemokines, antimicrobial peptides and other inflammatory mediators. To investigate the effects of a local inflammation on the expression levels of TLR4 and pro-inflammatory cytokines, 12 female rabbits received an intracervical infusion with either saline solution endotoxin-free (carrier, 2 mL; n = 6) or LPS (500 μg diluted in 2 mL of saline solution; n = 6). Blood samples were performed at 0, 30, 60 and 90 min and 2,4,6 and 24 h after treatment to evaluate interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) plasma concentrations. Animals were sacrificed 24 h post-treatment. The uterus and oviducts were immediately collected. The gene expression and protein levels of TLR4 and pro-inflammatory cytokines were detected by quantitative real-time PCR (qRT-PCR) and immuno-histochemical assay, respectively. Our study showed that the intracervical administration of LPS induced local inflammation given that the animals showed no clinical signs, the histological samples revealed signs of inflammation and plasma levels of pro-inflammatory cytokines were unchanged compared to the control. LPS produced an increase in the TLR4 mRNA expression levels in the uterus with respect to the control (P < 0.05). In LPS-treated rabbits the gene expression of IL-1β was higher in the uterus and oviducts and TNF-α only in the oviduct (P < 0.05) as compared to the control. The immuno-histochemical assay showed that TLR4, IL-1β and TNF-α were expressed in the reproductive tissues of the rabbit. Moreover, after the LPS stimulation the stromal cells of the uterus exhibited a higher staining for TLR4 (P < 0.05) and the epithelial cells of the oviduct for TNF-α and IL-1β (P < 0.05) with respect to the control. These results suggest that (1) TRL4, IL-1β and TNF-α are expressed in uterus and oviducts of the doe, and (2) LPS up-regulates the gene and protein expression of TLR4 and pro-inflammatory cytokines in uterus and oviducts. Therefore, the rabbit could be a useful animal model for studying the local mechanisms involved in reproductive dysfunctions caused by subclinical infections. [ABSTRACT FROM AUTHOR]