Neuroimmune characterization of optineurin insufficiency mouse model during ageing.

Optineurin is a multifunctional polyubiquitin-binding protein implicated in inflammatory signalling. Optineurin mutations are associated with amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), neurodegenerative diseases characterised by neuronal loss, neuroinflammation, and peripheral immune disbalance. However, the pathogenic role of optineurin mutations is unclear. We previously observed no phenotype in the unmanipulated young optineurin insufficiency mice (Optn470T), designed to mimic ALS/FTD-linked truncations deficient in polyubiquitin binding. The purpose of this study was to investigate whether ageing would trigger neurodegeneration. We performed a neurological, neuropathological, and immunological characterization of ageing wild-type (WT) and Optn470T mice. No motor or cognitive differences were detected between the genotypes. Neuropathological analyses demonstrated signs of ageing including lipofuscin accumulation and microglial activation in WT mice. However, this was not worsened in Optn470T mice, and they did not exhibit TAR DNA-binding protein 43 (TDP-43) aggregation or neuronal loss. Spleen immunophenotyping uncovered T cell immunosenescence at two years but without notable differences between the WT and Optn470T mice. Conventional dendritic cells (cDC) and macrophages exhibited increased expression of activation markers in two-year-old Optn470T males but not females, although the numbers of innate immune cells were similar between genotypes. Altogether, a combination of optineurin insufficiency and ageing did not induce ALS/FTD-like immune imbalance and neuropathology in mice.

Assessing whether progesterone-matured dendritic cells are responsible for retention of fertilization products in missed abortion.

We hypothesize that progesterone causes tolerogenic maturation of myeloid dendritic cells (DCs) in human decidua of threatened miscarriage or missed abortion characterized by a distinct phenotype and cytokine production, including reduction of the main NK cell proliferation and cytotoxic factor interleukin (IL)-15. During DC/NK cell interaction, progesterone-shaped DCs cannot efficiently multiply or equip NK cells with the cytotoxic mediators peforin and granulysin, which might harm trophoblasts and induce abortion. We propose that the presence, and maturation stage of decidual myeloid DCs be investigated using semi-quantitative immunohistological analyses and/or double-color immuno-fluorescent labeling of DC lineage and activation markers. The spatial arrangement of granulysin+ cells, NKp46+ NK cells, DCs, and trophoblasts might provide information about their mutual interactions in vivo. Multiple flow cytometry analyses of NK-receptors would provide insight into NK cell activation status. NK cell activation status could be also assessed by cytotoxicity assays against trophoblast cell lines, or isolated cognate extra-villous trophoblast cells. A correlation between decidual progesterone concentration or IL-15 expression, and the degree of DC maturation or the frequency of granulysin+ cells, might help to elucidate the mechanism of abortion retention in utero.

Granulysin-mediated apoptosis of trophoblasts in blighted ovum and missed abortion.

PROBLEM: Granulysin (GNLY) is a cytotoxic molecule mostly present in decidual natural killer (NK) cells. Blighted ovum (BO) and missed abortion (MA) represent the early pathological pregnancies with hindered development of the embryoblast or a dead embryo. We investigated the GNLY-mediated apoptotic mechanism potentially responsible for delayed termination of pregnancy. METHOD OF STUDY: We performed immunohistological and immunofluorescence labeling of decidual tissues (GNLY, Apaf-1, NF-κB). NKG2A expression was analyzed by flow cytometry and GNLY mRNA by RT-qPCR. RESULTS: The GNLY labeling intensity (H score) was lower in the nuclei of trophoblast cells in BO and MA. GNLY gene levels were inversely detected in BO and MA. A decreased decidual NK cell percentage was found in MA. NK cells from pathological pregnancies expressed lower NKG2A levels. The highest frequency of Apaf-1 was found in trophoblast cells of MA. NF-kB was highly expressed in decidual cells of BO. CONCLUSION: The reduced activation of GNLY-mediated killing might be implicated in the slower rejection of trophoblast cells in BO and MA. A decreased authentic decidual NK cell number could be responsible for low cytotoxicity against trophoblast cells in MA. In BO, trophoblast cells have a higher survival potential due to increased NF-kB expression.

Potential role of heat-shock protein 70 and interleukin-15 in the pathogenesis of threatened spontaneous abortions.

PROBLEM: The role of HSP70 and both its constitutive (Hsc) and inducible (Hsp) forms in the pathogenesis of threatened spontaneous abortions was investigated. METHOD OF STUDY: Immunohistology and/or immunofluorescence was used to analyze paraffin-embedded tissue sections, and reverse transcriptase-quantitative polymerase chain reaction and flow cytometry were used for analyses of decidual mononuclear cells (DMCs) and confocal microscopy for the detection of perforin, granulysin, and lysosome-associated membrane protein-1 (LAMP-1) in decidual lymphocytes (DLs). RESULTS: The percentage of single Hsp70(+) , Hsc70(+) , and IL-15(+) cells and mRNA levels of HSP70, CD91, and TLR4 were lower in the decidua basalis in cases of threatened miscarriages compared to that in cases of normal pregnancy. In a suspension of normal DMCs, IL-15 significantly decreased the HSP70 members and TLR4 in dendritic cells, T cells, and NK cells while increasing CD91 in NK cells alone. CONCLUSION: Downregulation of Hsc70, Hsp70, and IL-15 expression at gene and/or protein levels might support the retention of fertilization products in cases of missed abortion and blighted ovum.

Colocalization of Granulysin Protein Forms with Perforin and LAMP-1 in Decidual Lymphocytes During Early Pregnancy.

PROBLEM: Granulysin (GNLY) occurs in two forms, which have molecular weights of 9 and 15 kDa. We analyzed the cytotoxic potential of decidual lymphocytes (DLs) and peripheral blood lymphocytes (PBLs) based on the forms of GNLY that colocalizes with perforin (PER) and LAMP-1 following activation. METHODS: The forms of GNLY were detected by using confocal microscopy. We investigated the colocalization with PER and LAMP-1 in freshly isolated and activated DLs and PBLs. RESULTS: Activation of DLs and PBLs by K-562 cells increased the colocalization of 9 kDa GNLY with PER and LAMP-1. K-562 cells transfected with HLA-C decreased 9 kDa GNLY colocalization with PER in DLs only. IL-15 in DLs decreased 9 kDa GNLY and LAMP-1 colocalization, but increased both 15 kDa GNLY and LAMP-1, and PER and LAMP-1 colocalization. CONCLUSION: Activated DLs and PBLs show greater cytotoxic potential based on increased colocalization of 9 kDa GNLY and PER. HLA-C and IL-15 affect DLs, indicating their role in maintaining the pregnancy tolerance.

Possible role of granulysin in pathogenesis of osteoarthritis.

Increased presence of immune mediator and cytotoxic/apoptotic molecule granulysin was noticed in different tissues during pathological processes with the domination of Th1 over Th2 mediated immunity. Beside granulysin expression in T and NKT cells, activated NK cells are thought to be the major source of chemotactic 15 kDa and cytotoxic 9 kDa granulysin in vivo. As NK cells are the principal joint's tissue-infiltrating lymphocyte subset, we hypothesized that granulysin mediated human cell death (apoptosis) could be responsible for the relatively silent damage of the joint's tissue without clinically notable signs of systemic inflammation in the patients with osteoarthritis (OA). The analyzes of the presence and frequency of granulysin expressing lymphocytes at protein and gene levels in peripheral blood and synovial samples and/or the samples of joint's tissue after the joint replacement therapy in patients with OA could give the initial insight to evaluate our hypothesis. It would be of the particular interest to differentiate the expression of 9 kDa and 15 kDa granulysin forms in the effector cells, since only the shorter form exhibits cytotoxic properties. The measurement of granulysin mediated early apoptosis in human NK sensitive K562 cells could be suitable in vitro model for evaluating granulysin activity. Furthermore, disturbed balance of pro-inflammatory and anti-inflammatory cytokines in OA patients, could influence the level of the granulysin expression. Having in mind that the granulysin and its regulation is still unknown in the pathogenesis of OA, it could be worth to explore this important pro-inflammatory, cytotoxic/apoptotic mediator.

Mucins help to avoid alloreactivity at the maternal fetal interface.

During gestation, many different mechanisms act to render the maternal immune system tolerant to semi-allogeneic trophoblast cells of foetal origin, including those mediated via mucins that are expressed during the peri-implantation period in the uterus. Tumour- associated glycoprotein-72 (TAG-72) enhances the already established tolerogenic features of decidual dendritic cells with the inability to progress towards Th1 immune orientation due to lowered interferon (IFN)- γ and interleukin (IL)-15 expression. Mucine 1 (Muc 1) supports alternative activation of decidual macrophages, restricts the proliferation of decidual regulatory CD56(+) bright natural killer (NK) cells, and downregulates their cytotoxic potential, including cytotoxic mediator protein expression. Removing TAG-72 and Muc 1 from the eutopic implantation site likely contributes to better control of trophoblast invasion by T cells and NK cells and appears to have important immunologic advantages for successful implantation, in addition to mechanical advantages. However, these processes may lead to uncontrolled trophoblast growth after implantation, inefficient defence against infection or tumours, and elimination of unwanted immunocompetent cells at the maternal-foetal interface. The use of mucins by tumour cells to affect the local microenvironment in order to avoid the host immune response and to promote local tumour growth, invasion, and metastasis confirms this postulation.

Granulysin expression and the interplay of granulysin and perforin at the maternal-fetal interface.

Granulysin (GNLY) is a cytolytic/apoptotic molecule highly expressed in immune cells, particularly NK cells, at the maternal-fetal interface. The primary function of GNLY is to carry out lysis or apoptosis induction in target cells, tumor cells or cells infected by intracellular pathogens. To exert some of its functions GNLY needs to collaborate with perforin. The purpose of this study was to determine: (a) the expression of GNLY at the gene and protein levels at the maternal-fetal interface, (b) the relationship(s) between GNLY and perforin, and (c) GNLY secretion by NK cells stimulated by the NK-sensitive K562 cell line and its HLA-C and HLA-G transfectants. GNLY and perforin genes were found to be highly activated at the interface. GNLY mRNA was present at significantly higher levels compared with other cytolytic/apoptotic molecules. Confocal microscopy analysis showed that most first trimester pregnancy decidual lymphocytes simultaneously contained both GNLY and perforin protein in their cytoplasm, with a punctuate pattern consistent with granule localization. In contrast to peripheral blood, in unstimulated decidual lymphocytes GNLY and perforin rarely co-localized (10% of GNLY-positive cells and 20% of perforin-positive cells were positive for both proteins). Contact between decidual lymphocytes and K562 cells caused GNLY and perforin to be expressed in the same granules (approximately 50% co-localization), i.e., to attain the pattern seen in peripheral blood lymphocytes. The abundant GNLY secretion by decidual NK cells compared with peripheral blood NK cells after 2h of contact with the NK-sensitive K562 cells and K562 transfectants was striking.

Cell death mechanisms at the maternal-fetal interface: insights into the role of granulysin.

During mammal pregnancy, a sensitive balance between hormones, cytokines, humoral factors, and local cellular interactions must be established. Cytotoxic cells infiltrating the decidua are heavily equipped with cytolytic molecules, in particular perforin and granulysin. Granulysin is especially abundant in NK cells which are able to spontaneously secrete high quantities of granulysin. Besides being a potent bactericidal and tumoricidal molecule, granulysin is also found to be a chemoattractant and a proinflammatory molecule. The precise role(s) of granulysin at the maternal-fetal interface has not been elucidated yet. It is possible that it behaves as a double-edged sword simultaneously acting as an immunomodulatory and a host defense molecule protecting both the mother and the fetus from a wide spectrum of pathogens, and on the other hand, in case of an NK cell activation, acting as an effector molecule causing the apoptosis of semiallograft trophoblast cells and consequently leading to various pregnancy disorders or pregnancy loss.

Comparative study of frequency of different lymphocytes subpopulation in peripheral blood of patients with prostate cancer and benign prostatic hyperplasia.

PURPOSE: Benign prostatic hyperplasia (BPH) and prostate cancer (PC) are the most common urologic diseases among men over fifty and, until recently, they were considered to be caused by the impaired immune response. Despite many studies designed to investigate T-cell-based antitumor immunity, the role of innate immune cells in BPH and PC is still poorly understood. In this study the frequency of different leukocytes subpopulation in peripheral blood of BPH, PC patients and in healthy volunteers was analysed and compared. METHODS: In a cross-sectional study 60 subjects were enrolled (20 patients with BPH or with PC and 20 healthy volunteers). Peripheral blood mononuclear cells (PBMC) were isolated and the percentage of T lymphocytes, natural killer (NK) and NKT cells, as well as subsets of T lymphocytes [CD3(+)CD56(-)CD4(+), T(regs) (CD4(+)CD25(+)FoxP3(+)) and CD3(+)CD56(-)CD8(+)] and NK cells (CD3(-)CD56(+dim) and CD3(-)CD56(+bright)) were analysed by flow cytometry. Intracellular content of interleukin-4 (IL-4) and interferon gamma (IFNγ in T lymphocytes, NK and NKT cells were also detected. RESULTS: The percentage of T lymphocytes and their subsets in peripheral blood lymphocytes did not differ among investigated groups, while the frequency of Tregs was the highest in PC patients. The percentage of NK cell and their subsets did not differ among investigated groups. Negative correlation between PSA value, percentage of T lymphocytes and NK cells was observed only in PC patients. Highly positive correlation between the PSA value and the percentage of Tregs was found in PC patients. CONCLUSION: Different frequencies in distinctly lymphocyte subpopulation in peripheral blood of healthy men, BPH and PC patients could be responsible for occurrence and progression of prostatic hyperplasia or tumour. Due to the ability of tumours to suppress the cognate T cell immune response, the cells of innate immunity (NKT and Tregs) may be playing a key role in the immunopathogenesis of PC and BPH.