Analysis of the molecular diversity of Olea Europaea in the Mediterranean Island of Malta

The island of Malta is a small densely populated land mass located in the middle of the Mediterranean Sea. Genetic material from local olive tree varieties on the island was amplified using RAPD, 36 loci were subsequently generated and a dendrogram based on Jaccard’s similarity coefficient constructed. Analysis of clustering patterns indicated a high degree of genetic diversity (0.18–0.68), an early separation between the majority of the native varieties and more recently introduced varieties, supporting the idea of a history of limited genetic exchange and indicating a separate clustering for the majority of the ‘Malti’ and ‘Bidni’ varieties. Principal Component Analysis of banding patterns confirmed these clustering patterns and analysis of the incidence of bands for primers OPA-17, OPC-19, OPI-18 (vector correlation significance\0.01) as well as for OPAG-13, OPAN-15 (vector correlation between 0.01 and 0.05) showed strong correlation. Native Maltese varieties were characterised by a higher number of bands arising from the former group of primers indicating their use as a possible means to distinguish between local and imported varieties.peer-reviewe

A novel population of activated cytotoxic T cells infiltrate pituitary neuroendocrine tumour subytpes

Non-functional pituitary adenomas (NFPA) are non-hormone secreting pituitary tumours while growth hormone-secreting pituitary adenomas (GHPA) are active pituitary tumours causing acromegaly. Since immunotherapy is becoming the preferred therapeutic strategy in cancers, understanding the diversity of immune cells infiltrating the tumour microenvironment is warranted. However, little is known about the immune landscape of pituitary tumours. We validated an acoustic-assisted hydrodynamic focusing cytometer based method (Attune, Thermofisher) to identify rare immune cell populations in NFPA (n=6) and GHPA (n=3) obtained from patients undergoing transphenoidal surgery. We unravelled key cellular populations of myeloid (macrophages and monocytes) and lymphocytic (CD4 and CD8 T cells) origin using a multi-colour panel of antibodies against cell surface (CD45, CD163, CD64, CD11b, CD3, CD56, CD19, CD4 and CD8) and intracellular (CD68, T-bet, GATA-3 and FOXP3) antigens and assessed the degree of T-cell activation using the CD44 marker. We also checked for the expression of immune checkpoint and exhaustion markers PD1 and TIM-3 respectively. In all samples, lymphocytic infiltrates were detected. In all except 1 NFPA and in all GHPA the CD8:CD4 ratio was greater than 1 ranging from 1.88 - 5.74 in NFPA and 1.35 - 5.21 in GHPA with no statistical difference between NFPA and GHPA. This method also revealed novel populations of activated, cytotoxic T cells in all pituitary adenomas analysed. We are currently characterising the function of these cells in such tumours and how their presence correlates with the patients’ clinical data and tumour characteristics.peer-reviewe

Possible role of circulating bone marrow mesenchymal progenitors in modulating inflammation and promoting wound repair

Circulating bone marrow mesenchymal progenitors (BMMPs) are known to be potent antigen-presenting cells that migrate to damaged tissue to secrete cytokines and growth factors. An altered or dysregulated inflammatory cascade leads to a poor healing outcome. A skin model developed in our previous study was used to observe the immuno-modulatory properties of circulating BMMP cells in inflammatory chronic wounds in a scenario of low skin perfusion. BMMPs were analysed exclusively and in conjunction with recombinant tumour necrosis factor alpha (TNF) and recombinant hepatocyte growth factor (HGF) supplementation. We analysed the expression levels of interleukin-8 (IL-8) and ecto-50-nucleotidase (CD73), together with protein levels for IL-8, stem cell factor (SCF), and fibroblast growth factor 1 (FGF-1). The successfully isolated BMMPs were positive for both hemopoietic and mesenchymal markers and showed the ability to differentiate into adipocytes, chondrocytes, and osteocytes. Significant differences were found in IL-8 and CD73 expressions and IL-8 and SCF concentrations, for all conditions studied over the three time points taken into consideration. Our data suggests that BMMPs may modulate the inflammatory response by regulating IL-8 and CD73 and influencing IL-8 and SCF protein secretions. In conclusion, we suggest that BMMPs play a role in wound repair and that their induced application might be suitable for scenarios with a low skin perfusion.peer-reviewe