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Biomedical subjects

D Rukavina

Publications and source records attributed to D Rukavina.

At least 19 recordsLinked to original sources
PubMed2006

Human decidual NK cells: unique phenotype and functional properties -- a review.

Human decidual NK cells are massively recruited at the site of embryonic implantation (decidua basalis). They differ in many ways from their peripheral blood NK cell counterparts in terms of gene expression, phenotype and functionality. The major subpopulation of decidual NK cells is CD56(bright) whereas the minor subset is CD56(dim), contrasting with the peripheral blood NK cells whose major subpopulation is CD56(dim). Decidual NK cell cytolytic function is much reduced despite the presence of several activating receptors and the essential machinery required for lysis. Decidual NK cells produce a number of cytokines that are not normally secreted by peripheral blood NK cells. Human decidual NK cell potential functions at the maternal-fetal interface are not yet clearly established but several hypotheses are being evaluated, including control of extravillous invasion, control of uterine vascular remodeling, and local anti-viral activity.

Cell Movement↗
PubMed2005

The presence of functional mannose receptor on macrophages at the maternal-fetal interface.

BACKGROUND: The mannose receptor (MR) is involved in the initiation of the immune response and regulation of homeostasis during inflammation and tissue remodeling. METHODS: Distribution, endocytosis and possible natural ligand tumor associated glycoprotein-72 (TAG-72) for the MR have been examined by immunohistology, immunocytochemistry and flow cytometry at the maternal-fetal interface, characterized by extensive tissue remodeling. RESULTS: Contrary to disseminated distribution of the MR positive (MR+) cells in term placenta, the MR+ cells of early pregnancy decidua intimately surrounded glands and followed tissue distribution of CD14 positive cells. The mannose receptor was present on freshly isolated first trimester decidual mononuclear cells and distributed mostly on macrophages (77.08 +/- 10.55%, mean +/- SD). The expression of the MR on CD14 positive cells decreased following 18 h culture (P < 0.01) and was accompanied by the reduction of fluorescein isothiocyanate (FITC)-dextran uptake. PAM-1 anti-MR antibody, mannan and TAG-72 reduced FITC-dextran uptake by decidual macrophages. CONCLUSIONS: These data indicate that the MR+ macrophages, surrounding early decidual glands, are able to internalize ligands for carbohydrate recognition domain of the receptor, including decidual secretory phase mucin TAG-72.

Antigens, Neoplasm↗
PubMed2004

Perforin expression in peripheral blood lymphocytes and skin-infiltrating cells in patients with lichen planus.

BACKGROUND: Current evidence suggests that lichen planus is a T-cell-mediated autoimmune disease in which cytotoxic mechanisms have been poorly investigated. OBJECTIVES: We investigated the expression of perforin in subpopulations of peripheral blood lymphocytes (PBL) in exacerbation and remission phases of the disease as well as in skin lesions. METHODS: We performed a simultaneous detection of perforin (intracellular molecule) and cell surface antigens on PBL by flow cytometry, and skin lesions were investigated by immunohistochemistry. RESULTS: The most interesting finding was a significant increase of perforin expression in cytotoxic T lymphocytes (CD3+ perforin+ cells) in the exacerbation phase of disease (P < 0.05), which was mostly located in the CD8+ subpopulation (CD8+ perforin+) (P < 0.01). Using immunohistochemistry we confirmed the infiltration of T lymphocytes in skin lesions, especially of CD4+ and CD8+ phenotypes, compared with uninvolved (P < 0.05) and healthy skin (P < 0.01). The expression of perforin was also significantly higher in lesional skin compared with nonlesional and healthy skin (P < 0.05). CONCLUSIONS: Our results clearly show the upregulation of perforin expression in peripheral blood as well as in lesions of patients with lichen planus and therefore suggest an important role for perforin in this autoimmune disease.

Adult↗
PubMed2004

Perforin expression is upregulated in the epidermis of psoriatic lesions.

BACKGROUND: There are currently very few data regarding the role of cell-mediated cytotoxicity in psoriasis. Both cytotoxic T lymphocytes and natural killer (NK) cells mediate cytotoxicity reactions, mainly by two distinct pathways, the perforin/granzyme and the Fas/Fas ligand pathway. OBJECTIVES: To study the expression and distribution of perforin, T- and NK-cell subsets in psoriatic lesional and nonlesional skin. METHODS: Skin biopsy specimens from both lesional and nonlesional skin of 11 patients with chronic plaque psoriasis and eight healthy controls were analysed by immunohistochemistry. RESULTS: We found a significant increase in CD4+ and CD8+ cells in psoriatic lesions compared with nonlesional and healthy skin. The expression of CD16+ NK cells was significantly lower in lesions compared with healthy skin. Perforin expression was significantly enhanced in the epidermis of psoriatic lesions. CONCLUSIONS: Perforin expression is upregulated in the epidermis of psoriatic lesions, suggesting a potential role for perforin in the creation of the psoriatic plaque.

Adult↗
PubMed2003

Syngeneic pregnancy induces overexpression of natural killer T cells in maternal liver.

Conditions such as stress, infection, autoimmune disease, etc. elevate the number and function of extrathymic T cells that are generated mainly in the liver. As primitive, self-reactive clones of T cells that coexpress receptors of the natural killer (NK) lineage, they mediate cytotoxicity against altered self, malignant and infected cells and have the unique potential to rapidly secrete large amount of T helper 1 (Th1) or Th2 cytokines. To elucidate whether some of these changes occur even during the syngeneic pregnancy, we made phenotypic and functional characterization of mononuclear lymphatic cells (MNLCs) isolated from the liver and spleen of pregnant C57BL/6 mice, testing their cytotoxicity against syngeneic thymocytes as well as against NK- and lymphokine-activated killer (LAK)-sensitive targets. The data have shown that on the sixteenth day of syngeneic pregnancy TCRint, NK1.1+ and IL-2Rbeta+ cells were accumulated in the liver, while the quantities of CD4+ and CD8+ T cells and total number classical NK (NK1.1+CD3- or IL-2Rbeta+CD3-) cells were increased in the spleen. Pregnancy-activated hepatic and splenic MNLCs were more cytotoxic against syngeneic thymocytes, YAC-1 and P815 targets, suggesting that the maternal liver is a main producer of autoreactive NKT clones, which subsequently augment NK- and LAK cell-mediated cytotoxicity in the liver and spleen.

Animals↗
PubMed2001

Regeneration and tolerance factor of the human placenta induces IL-10 production.

Regeneration and tolerance factor (RTF) was originally identified in the placenta of mice and the isolated protein shown to have suppressive effects. In these studies, the gene cloned from thymus tissue was mapped to human chromosome 12. The role of recombinant RTF on cytokines was examined. In addition, we examined the human placenta by immunohistochemistry for RTF expression. RTF was expressed at the peripheral layer of cytotrophoblast in 7-9-week-old placentas. Using the RTF gene sequence, a recombinant protein was prepared and shown to induce IL-10 production. These data indicate that RTF is expressed by the tissues most intimately involved at the maternal-fetal interface, and its biological activity is capable of producing the necessary immune response for initiating and maintaining the maternal-fetal relationship.

Cells, Cultured↗
PubMed2001

Modulatory effects of octreotide on anti-CD3 and dexamethasone-induced apoptosis of murine thymocytes.

In an attempt to elucidate the effects of somatostatin on two crucial processes that regulated T-cell differentiation and selection in thymus in this study, we investigated in vivo and in vitro the effects of octreotide (SMS 201-995) on dynamics of apoptosis, induced by dexamethasone (DEX) or by anti-CD3 monoclonal antibodies (mAb). The data were estimated by analysis of absolute cellularity, DNA fragmentation and maturational stage of thymocytes, detecting the CD4 and/or CD8 and T cell receptor (TCR) expression on thymocytes. The results, obtained by estimation of subdiploid peak of DNA and ladder DNA formation, have shown that SMS given in vivo, may potentiate the early phase of DEX-induced nuclear fragmentation (at 24 h), accelerating simultaneously the elimination of thymic cells with double positive (DP) CD4high CD8high phenotype (expressed both as percentage and absolute number). On the contrary, SMS, given both in vivo and in vitro, down-regulated the late process (at 72 h) of nuclear fragmentation, induced by anti-CD3 mAb, minimizing simultaneously the elimination of DP cells (expressed both as percentage and absolute number). In anti-CD3-treated cultures of thymocytes, SMS retarded also the elimination of immature thymocytes, expressing the TRC alpha/betalow or intermediate phenotype. The data emphasize that octreotide might have important regulatory effect on processes of thymic differentiation and maturation, which are crucial for T cell selection, induction of tolerance and prevention of autoimmune diseases.

Animals↗
PubMed2001

The involvement of CD14 in the activation of human monocytes by peptidoglycan monomers.

BACKGROUND: Cell-wall components of Gram-positive and Gram-negative bacteria induce the production of cytokines in human peripheral blood mononuclear cells. These cytokines are the main mediators of local or systemic inflammatory reaction that can contribute to the development of innate immunity. AIMS: This study was performed to analyze the involvement of CD14 molecule in the activation of human monocytes by peptidoglycan monomer (PGM) obtained by biosynthesis from culture fluid of penicillin-treated Brevibacterium divaricatum NRLL-2311. METHODS: Cytokine release of interleukin (IL)-1, IL-6 and tumor necrosis factor-alpha from human monocytes via soluble CD14 (sCD14) or membrane-associated (mCD14) receptor using anti-CD14 monoclonal antibody (MEM-18) or lipid A structure (compound 406) was measured in bioassays. RESULTS: The results demonstrated that PGM in the presence of human serum might induce the monokine release in a dose-dependent manner. The addition of sCD14 at physiologic concentrations enhanced the PGM-induced monokine release, while the monokine inducing capacity of PGM in the presence of sCD14 was inhibited by MEM-18. Effects of PGM were also blocked by glycolipid, compound 406, suggesting the involvement of binding structures similar to those for lipopolysaccharide. CONCLUSION: Activation of human monocytes by PGM involves both forms of CD14 molecule, sCD14 and mCD14.

Acetylmuramyl-Alanyl-Isoglutamine↗
PubMed2001

Changes of cytolytic cells and perforin expression in patients with posttraumatic stress disorder.

AIM: To define phenotypic characteristics of cytotoxic T lymphocytes (CTL) and natural killer cells (NK) in peripheral blood, frequency of somatic symptoms, and level of anxiety and depression in 25 patients clinically diagnosed with chronic post-traumatic stress disorder (PTSD). METHODS: Patients were divided into two sub-groups according to the stressor: 18 PTSD patients with the battlefield experience and 7 PTSD patients with battlefield experience who were tortured as the prisoners of war (POW) in Bosnian-Serbian camps. The control group consisted of 15 healthy volunteers matched to the patients by sex and age. We tested all patients using Becks depression inventory, Spielberger anxiety test, and somatic disturbance list, and analyzed their peripheral blood lymphocytes using flow cytometry with the double fluorescence staining of cell surface antigens (CD3, CD4, CD8, CD16, and CD56) and intracellular cytolytic molecule perforin (P), a mediator of cytolytic action at the molecular level. RESULTS: All PTSD patients showed a significant level of anxiety, depression, and numerous somatic symptoms. The only significant difference between PTSD patients with and without POW experience was in the anxiety level (median, 71; range 61-79; vs median, 65; range, 49-77). PTSD patients with POW experience had significantly higher levels of CD16+ cells (median, 37%; range, 16-55%) than those without it (median, 12%; range, 5-37%). Double labeling for intracellular P antigen and cell surface antigens showed the highest levels of CD16+P+ (median, 33%; range, 15-40%; vs median, 10%; range, 3-29%) and CD56+P+ (median, 21%; range, 11-40%; vs median 8%; range, 1-30%) cells in PTSD-POW patients. CONCLUSION: Chronic PTSD patients who survived concentration camps show the most numerous alterations in PBL phenotype, the highest number of perforin-containing cells, and a significantly higher level of anxiety.

Adult↗
PubMed2000

Assessment of perforin expression in peripheral blood lymphocytes in psoriatic patients during exacerbation of disease.

There are very few data concerning the role played by cell-mediated cytotoxicity, particularly at the molecular level, in the course of psoriasis. Both cytotoxic T lymphocytes (CTL) and natural killer cells contain in their granules the cytolytic protein perforin, a mediator in cell-mediated cytotoxicity reactions. The aim of this study was to analyze perforin expression in various sets and subsets of perforin-positive peripheral blood lymphocytes in 17 patients with chronic psoriasis vulgaris in the exacerbation phase. The results were compared with those of an age- and sex-matched healthy control group (n = 21). Perforin (intracellular antigen) and cell surface antigens were detected using the simultaneous double-staining method. We found a significant increase in perforin (P) expression in the patient group for CTL (CD3+P+ cells), which are located mostly in the CD8+ population of T lymphocytes (CD8+P+).

Acute Disease↗
PubMed2000

Immunoprotective properties of peptidoglycan monomer linked with zinc in cholestatic jaundice.

BACKGROUND: Previously it was shown that a new immunostimulator, peptidoglycan monomer linked with zinc (PGM-Zn), might have immunocorrective and hepatotropic effects. Owing to this in the present study we investigated its effects on jaundice-induced immunodysfunction, which might be responsible for serious peri- and postoperative complications in biliary obstruction. METHODS: In vivo effects of PGM-Zn were analyzed in mice subjected to common bile duct ligation (CBDL), where we estimated phenotypic profile and cell cycle of thymocytes, splenocytes and phagocytic function of peritoneal macrophages. In vitro effects of PGM-Zn were evaluated on blastogenesis of human peripheral blood mononuclear cells (PBMNC), obtained from healthy donors and stimulated with anti-CD3 monoclonal antibody and/or PMA, in the presence or absence of jaundice serum obtained from patients with biliary calculosis. RESULTS AND DISCUSSION: Jaundice induced marked disarrangement of lymphatic homeostasis, which at several points might be blocked by PGM-Zn. In mice it delayed the CBDL-induced decline of CD4+ CD8+ thymocytes, decreased the proportion of CD8+ T cells, and increased the percentage of CD4- CD8- thymocytes, augmenting simultaneously the proportion of thymic cells in S and G2 + M phase of cycle. Similar hyperplastic reaction with increased percentage of CD4+, Ig+ and CD5+ cells was noticed in the spleen, together with the enhanced phagocytic ability of peritoneal macrophages. In human PBMNC jaundice reduced the percentages of CD3, CD5, CD4, CD8 and HLA-DR-expressing cells and increased the proportion of CD25 and perforin-positive lymphocytes. PGM-Zn given in vitro was able to abrogate the antiproliferative activity of jaundice serum on PMA and anti-CD3 + PMA-induced blastogenesis.

Acetylmuramyl-Alanyl-Isoglutamine↗
PubMed1999

Progesterone directly and indirectly affects perforin expression in cytolytic cells.

PROBLEM: Decidual lymphocytes (DL) expressing the cytolytic molecule perforin represent approximately 55% of DL in the first trimester of human pregnancy. Progesterone dominates this phase of pregnancy and controls the production of uterine cytokines and growth factors. The aim of this study was to investigate the role of progesterone and progesterone-induced blocking factor (PIBF) on perforin expression in DL and peripheral blood lymphocytes (PBL). METHOD OF STUDY: Perforin expression was analyzed in PBL and DL incubated either in culture medium or with decidual adherent cells (DAC) and peripheral blood adherent cells (PBAC) and their supernatants with or without progesterone or PIBF. Perforin was detected by flow cytometry in PB and in decidual first trimester pregnancy lymphocytes. RESULTS: Progesterone in high concentrations directly affects perforin expression in DL but not in PBL. Progesterone in a concentration dependent manner indirectly blocks perforin expression in DL and PBL cultured with adherent cells or their supernatants. PIBF blocked upregulation of perforin expression of DL cultured with DAC, but none of those cultured with PBAC. Similarly, PIBF was inefficient when PBL or DL were cultured with PBAC. CONCLUSION: Progesterone present in a high concentration locally at the maternal-fetal interface modulates perforin expression in the first trimester pregnancy DL.

Cells, Cultured↗
PubMed1999

Human decidualized endometrial T lymphocytes do not substantially down-regulate CD3zeta.

PROBLEM: The T-cell antigen receptor (TCR) has been reported to be down-regulated on T-cells in the decidualized endometrium in early pregnancy. METHOD OF STUDY: The expression of CD3zeta, a component of the TCR complex, has been investigated in human first-trimester decidual T-cells using flow cytometric analysis of permeabilized cells. RESULTS: Levels of CD3zeta expression were significantly lower in decidual than in peripheral T-cells from non-pregnant women, as assessed by mean fluorescence intensity (4.2 vs. 5.5, logarithmic scale, P < 0.05). However, when decidual and peripheral T-cells from the same subjects were analyzed (n = 10), mean levels of CD3zeta were slightly, but not significantly, lower in decidual than in peripheral T-cells (P > 0.1). CD3zeta was not substantially down-regulated systemically as mean cytoplasmic CD3zeta levels did not differ significantly between peripheral blood T-cells from pregnant women and non-pregnant controls (P > 0.2). CD8+ cells outnumber CD4+ cells in decidua, but neither the proportions of these two T-cell subsets positive for cytoplasmic CD3zeta nor the mean levels of CD3zeta were significantly different. CONCLUSIONS: These results indicate that human decidual T-cells do not greatly down-regulate CD3zeta, but it is unclear if a small decrease in mean levels may be sufficient to compromise their capacity for activation.

CD3 Complex↗
PubMed1999

Modulation of perforin expression in the decidual and peripheral blood cytotoxic lymphocytes in culture.

PROBLEM: Perforin (P) is a cytolytic molecule located in intracellular granules of cytotoxic lymphocytes both in the peripheral blood and decidua of pregnancy. The aim was to analyze the kinetics of P expression during in vitro culture and modulation of P expression by adherent cells, their supernatants and mitogen (PHA) stimulation. METHOD OF STUDY: P (intracellular antigen) was detected by flow cytometry in the suspension of first trimester pregnancy peripheral blood lymphocytes (PBL) and decidual lymphocytes (DL). RESULTS: A decrease of the percentage of P+ cells was obtained after 1 hr incubation and was prevented by addition of 30% of decidual adherent cells (DAC) or their supernatants. Upregulation of P expression was obtained when, in addition to adherent cells, DL and PBL were stimulated by PHA. DAC present in the culture in physiological concentrations prevent downregulation of P expression. CONCLUSION: DAC located in the vicinity of decidual cytotoxic lymphocytes, owing to their unique ability to produce a wide range of substances on demand, contribute to the high level of P expression in the decidua of pregnancy.

Cells, Cultured↗
PubMed1999

On the role of T lymphocytes in stimulation of humoral immunity induced by peptidoglycan-monomer linked with zinc.

Effects of peptidoglycan linked with zinc (PGM-Zn) were investigated on plaque-forming cell (PFC) generation to sheep red blood cell (SRBC) and SRBC-unrelated antibody production in primary and secondary immune response in mice depleted in vivo of CD4+ and/or CD8+ T lymphocytes. PGM-Zn in nondepleted mice stimulated the PFC generation and IgM or IgG and IgG1 production in primary and secondary reaction. Single depletion of CD4 or CD8+ T cells did not change this ability. The effects of PGM-Zn after CD8+ depletion were even greater than those in nondepleted mice. Depletion of both T cell subsets, however, completely abrogated immunostimulatory effects of PGM on PFC generation (primary and secondary response), as well as on primary SRBC-unrelated antibody production, leaving only the increase of IgG in secondary response unchanged. Immunostimulatory effects and isotype switching to IgG1 and IgG2a correlated with the changes in splenic CD4+, CD8+, CD5+ cells, pointing to the regulatory role of these cells and/or their cytokines in PGM-Zn-induced immunostimulation. Altogether the data suggest that PGM-Zn may potentiate the costimulatory signals coming from activated T cells and act on B cells without the T cell help.

Acetylmuramyl-Alanyl-Isoglutamine↗
PubMed1999

Progesterone-induced blocking factor inhibits degranulation of natural killer cells.

PROBLEM: During the first trimester of pregnancy, nonclassical (CD3-, CD56+, CD16-, perforin [P]bright+) natural killer (NK) cells comprise the major decidual lymphocyte population. These cells, in spite of their high perforin content, exert a low cytolytic activity. Peripheral blood lymphocytes of healthy pregnant women produce progesterone-induced blocking factor (PIBF), which inhibits NK activity. PIBF-producing cells are likely to be present in decidua and might contribute to low decidual NK activity. METHOD OF STUDY: Decidual cells obtained from elective pregnancy termination were double labeled for CD56 and PIBF. We tested the effect of PIBF on perforin liberation by activated peripheral blood NK cells. RESULTS: Sixty percent of decidual lymphocytes were CD56 + and expressed PIBF at the same time. PIBF-treated and untreated peripheral blood NK cells were incubated with K-562 cells, and perforin content of target conjugated NK cells was detected with immunocytochemistry. PIBF treatment of peripheral blood lymphocytes significantly reduced lysis of K-562 cells. Among target bound lymphocytes in PIBF-treated samples, we found a significantly (P < 0.01) higher rate of P+ cells than in untreated samples. CONCLUSIONS: These data suggest that PIBF inhibits cytotoxicity of NK cells via a block of degranulation, and since decidual NK cells are PIBF+, it cannot be ruled out that this effect of PIBF contributes to low decidual NK activity.

CD56 Antigen↗
PubMed1999

Decidual macrophages are the population of decidual adherent cells which regulates perforin expression in cytolytic cells.

PROBLEM: We have shown that addition of decidual adherent cells (DAC) to the culture of decidual lymphocytes (DL) prevents the downregulation of perforin expression in these cells. Because DAC are a mixture of various cell populations, the aim is to analyze immunophenotypic characteristics of DAC and to determine which cell population is involved in the regulation of perforin expression. METHOD OF STUDY: First trimester pregnancy decidual cells were obtained by enzymatic tissue digestion. Decidual cells and peripheral blood lymphocytes (PBL) were centrifuged on Ficoll-Hypaque density gradient and cultured overnight to obtain adherent cells, which were analyzed by flow cytometry and immunocytochemically. RESULTS: Almost all peripheral blood adherent cells (PBAC) (ca 90%) expressed monocyte/macrophage markers but only 10-20% of DAC. The rest of DAC expressed markers of stromal cells. HLA-DR depleted population of DAC (stromal cells only) could not prevent downregulation of perforin expression in cultured DL and PBL. CONCLUSION: Decidual macrophages are involved in the regulation of perforin expression in DL.

Cell Adhesion↗