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D Rukavina

Publications and source records attributed to D Rukavina.

At least 37 records · Page 2Linked to original sources
PubMed1998

Age-related decline of perforin expression in human cytotoxic T lymphocytes and natural killer cells.

In this study a flow cytometric technique for detecting cytoplasmic perforin (P) has been used to quantify age-related changes in perforin expression in human peripheral blood lymphocytes (PBL). Proportions of P+ lymphocytes increased after birth, but declined rapidly after the age of 70 years. This was true for both T cells and CD16(+) and CD56(+) natural killer (NK) cells. Children showed in addition to high levels of perforin positive CD8(+) cells a much higher proportion of CD4(+)P+ cells than the other age groups. In elderly individuals there was also a highly significant reduction in mean levels of perforin per cell as compared with all other groups (P < .05 to .001). Adult women had consistently higher mean levels of perforin per cell than adult men for all P+ cell phenotypes. Functional tests clearly showed the deficiency in early spontaneous cytotoxic potential of PBL from elderly persons due to relative P deficiency, which can be corrected by stimulation of cytolytic cells with target cells and interleukin-2 (IL-2). The deficiency in cytolytic activity on the contact with target cells may have implications for antiviral and antitumor immunity in elderly persons.

Adult↗
PubMed1998

Tissue zinc dynamics during the immune reaction in mice.

Owing to the importance of zinc for the functioning of the immune system, the role of endogenous Zn, located both in lymphoid and nonlymphoid organs, was investigated during the standard humoral and cellular types of immune response. For this purpose, the dynamics of hepatic, thymic, splenic, and renal Zn content was determined in mice sensitized with (a) sheep red blood cells and (b) semiallogeneic lymphocytes during the local host vs graft reaction (HVGR). The data obtained by ion-coupled plasma spectrometry revealed that the humoral type of immunity is characterized by a significant increase of Zn concentration in the liver and in the thymus. Simultaneously, linear regression analysis showed that the generation of plaque-forming cells in the individual mouse was highly positively correlated with Zn concentration in the liver (r=0.897), and spleen (r=0.833), and negatively with Zn concentration in the thymus (r=-0.624). Similar relationships between the intensity of local immune reaction and tissue Zn levels were found in local HVGR at the fifth day in the liver and spleen (r=0.861 and r=0.695, respectively), at the seventh day in the thymus (r=-0.797), and at the tenth day in the liver (r=-0.859). The data emphasize the necessity of Zn for the development of normal immune response and point to the existence of a Zn-dependent hepato-thymic axis during the humoral and cellular types of immune reactivity.

Animals↗
PubMed1997

Increased perforin expression in multiple sclerosis patients during exacerbation of disease in peripheral blood lymphocytes.

The expression of perforin (P) in subpopulations of the PBL of multiple sclerosis (MS) patients in stable and active phase of disease was investigated, by simultaneous detection of P (intracellular molecule) and cell surface antigens. A significant increase of CD4+P+ (p < 0.02) and CD16+P+ (p < 0.001), and decrease of CD56+P+ (p < 0.05) cells in active MS was found. In active disease there is a highly significant increase (p < 0.001) of average fluorescence intensity (AFI) for P in CD4(dim+) cells, and these cells are larger in size and have higher granularity (p < 0.05) compared to CD4(bright+) p(dim+) cells. Surprisingly, there were no CD25+P+ cells in either group of MS patients. These results show that CD4+P+ cells are upregulated in active disease in cell number, in the level of P expression per cell, and in the level of cell activation (increase in cell size and granularity). It is suggested that CD4+P+ cytotoxic cells may play a role in the pathogenetic mechanisms of MS.

Adult↗
PubMed1997

Perforin-expressing lymphocytes in peripheral blood and decidua of human first-trimester pathological pregnancies.

PROBLEM: We have shown previously that the decidua of first-trimester human pregnancy is heavily infiltrated with perforin-positive cells. The aim was to detect expression of perforin in both decidual lymphocytes (DL) and peripheral blood lymphocytes (PBL) in the first trimester of pathological pregnancies: Anembryonic pregnancy and missed abortion. METHOD: Decidual tissue from a normal pregnancy group and from pathological pregnancies was obtained by vaginal curettage. Perforin (an intracellular antigen) and the cell surface antigens CD3, CD4, CD8, CD16, CD56, CD11c, and CD45RA were quantified simultaneously by flow cytometric analysis. RESULTS: In the missed abortion group, we found: 1) a relative decrease in the frequency of both CD4+P+ cells and CD56+P+ cells as well as the mean fluorescence intensity for perforin; 2) a relative increase of CD16+P+ PBL cells; and 3) a relative increase of CD4+ cells in PBL compared with anembryonic pregnancy and normal pregnancy. There was also a significant relative decrease in the proportion of CD4+ and CD8+ cells among perforin-positive PBL in both anembryonic pregnancy and missed abortion. CONCLUSION: Our results show that significant decreases in the prevalence of perforin-positive lymphoid cells, their subpopulations, and mean fluorescence intensity for perforin are associated with pregnancy failure.

Abortion, Missed↗
PubMed1997

Membrane phenotype and expression of perforin and serine esterases by CD3- peripheral blood and decidual granular lymphocyte-derived clones.

PROBLEM: Human first-trimester pregnancy decidua were found to contain large numbers of perforin (P)-containing cells, which varied in their membrane antigen phenotype. In this study results obtained by analyzing CD3- clones derived from human early pregnancy decidua and peripheral blood are reported. METHOD OF STUDY: Decidual tissue was obtained from vaginal termination of first trimester normal human pregnancies. CD3- clones were generated by limiting dilution cloning after the depletion of CD3+ lymphocytes. The cell membrane phenotype was determine by flow cytometry. Perforin was detected by fluorescence-activated cell sorter (FACS) analysis of permeabilised cells. Serine esterases (SE) were identified by histochemical staining for BLT-esterase. RESULTS: Cloned decidual cell populations retained the overall antigenic phenotype of freshly isolated decidual natural killer (NK)-like cells. All CD3- clones, either derived from decidua or from peripheral blood contained perforin. Serine esterases were present in every decidual clone analyzed. CONCLUSIONS: Limiting dilution cloning allows the clear-cut analysis of homogenous subsets of decidua-derived NK-like clones. The presence of large amounts of perforin in all of the CD3- clones underlines the extensive transcription of the perforin gene by NK-like lymphocytes.

Antigens, Surface↗
PubMed1997

Down-regulated expression of perforin-positive/CD16+ cells in the peripheral blood lymphocytes in the first trimester of pregnancy and up-regulation at the end of pregnancy.

PROBLEM: Immunophenotypic profiles of perforin (P)-positive peripheral blood lymphocytes in the first trimester and at the term of human pregnancy were analyzed. METHOD OF STUDY: Perforin expression in peripheral blood lymphocyte subsets was measured by simultaneous detection of P (intracellular antigen) and cell-surface antigens (CD3, CD4, CD8, CD16, and CD56) by flow cytometry in nonpregnant (NP) and pregnant women in the first trimester (FTP) and at the time of parturition (TP). RESULTS: The percentage of total P+ cells in peripheral blood compared to nonpregnant women was slightly lower in the FTP but significantly higher at TP. Perforin-positive cells were significantly elevated in T lymphocyte subsets (CD3+P+, CD4+P+, CD8+P+) in both the FTP and TP groups, as was the percentage of CD56+P+ cells. Profound changes in the CD16+ subpopulation were found in the FTP group compared to both the NP and TP groups (a drastic decrease of CD16+P+ cells; CD16+ cells among P+ cells; P+ cells among CD16+ cells). A considerable part of CD3+ cells in both the FTP and TP groups are CD3+CD56+P+. The average fluorescence intensity (AFI) for P (a measure of P content per cell) was significantly decreased in FTP and increased in TP groups. CONCLUSIONS: The CD16 molecule is Fc gamma RIIIA which is the only Fc receptor responsible for antibody dependent cell-cytotoxicity (ADCC) of NK and T-cells. In the first-trimester human pregnancy this mechanism is severely down-regulated compared to both the NP and TP groups.

Animals↗
PubMed1996

Perforin expression in peripheral blood lymphocytes in rejecting and tolerant kidney transplant recipients.

Perforin (P) is a cytolytic molecule expressed in the granules of cytolytic T cells and natural killer cells. Although cytotoxic cells have been implicated in graft rejection, no prospective clinical study has been published that examines the dynamics of perforin expressing cells in peripheral blood lymphocytes of transplanted patients. The cytofluorimetric assay developed in our laboratory previously for the simultaneous detection of intracellular perforin together with cell surface molecules was used for posttransplantation monitoring of patients, for the assessment of the efficiency of immunosuppressive treatment, and for the prediction of acute kidney transplant rejection and the stability of tolerance to long lived kidney transplants. Immunosuppression for the purpose of allotransplantation causes a decline in the number of perforin-expressing cells in peripheral blood. In contrast, in patients with clinical signs of acute rejection, the total number of perforin-expressing lymphocytes was increased in comparison with nonrejecting patients. Analyzing perforin-expressing subsets, rejection crises were accompanied by a relative decrease of perforin expression in the CD4+ subpopulation while increasing in the CD8+ subset. In the CD56+ and CD16+ NK subpopulations changes in perforin expression were mixed. In nonrejecting patients the ratio of perforin expression in CD4+ cells was high compared with CD8+ cells. Intensive therapy of acute rejection episodes with high doses of corticosteroids (methylprednisolonet [Solumedrol] bolus) strongly and significantly decreased the percentage of both, the subpopulations of perforin-positive T cells and the subpopulation of CD56+P+ NK cells. The lowest level of perforin expression, including low frequencies of perforin among CD8+ and CD4+ cells, was found in the group of patients tolerating transplanted kidneys for several years. These changes in perforin protein expression in peripheral blood can be used to discriminate between immunosuppressed patients who are immunologically quiescent and those who undergo transplant rejection. Our results confirm the hypothesis that cytotoxicity mediated by perforin may be an important effector mechanism in the rejection of allografted kidneys.

Biomarkers↗
PubMed1996

Expression of membrane form of the pregnancy associated protein TJ6 on decidual lymphocytes in the first trimester of pregnancy.

TJ6, a newly described protein produced locally in the uterine decidua during pregnancy, may be involved in maintaining a unique immunological environment at the maternal-fetal interface. The aim of this study was to determine whether TJ6 is expressed as membrane form on decidual lymphocytes (DL), to define the phenotypes of TJ6m (membrane form TJ6) expressing cells and to analyze the fluorescence intensity of TJ6m expression. Peripheral blood lymphocytes (PBL) and DL were obtained from first trimester pregnancies undergoing elective termination and immunophenotyped for TJ6m and other cell surface antigens (CD3, CD8, CD19, CD56, CD16) by flow cytometry. This is the first study showing that TJ6 molecules are present on decidual lymphocytes in human pregnancy. TJ6m expression on PBL was not different from that of DL. However, a significantly higher percentage of double positive (TJ6m+CD3+, TJ6m+,CD8+,TJ6m+CD19+) cells were found in PBL when compared to DL. The average fluorescence intensity (AFI) for the TJ6m marker among cells with CD8+, CD19+ and CD56+ double positive was significantly higher in DL as compared with those of PBL. The AFI for granularity of double positive DL was significantly higher than observed in PBL.

Antigens, CD↗
PubMed1996

Expression of functional molecules by human CD3- decidual granular leucocyte clones.

Cell surface and cytoplasmic antigen expression by 35 CD3- decidual granular leucocyte (DGL) clones, derived from human endometrial tissue in the first trimester of pregnancy, has been compared with both that of fresh CD3- decidual leucocytes and that of CD3- peripheral blood natural killer (PBNK) cell clones (n = 12). The majority of DGL clones retained the antigenic phenotype of fresh cells, although CD103 (HML-1) was expressed on 50% of DGL clones but only 17% of fresh DGL. Both cytoplasmic CD3 zeta and CD3 epsilon chains were detected in > 90% of DGL clones in the absence of cell surface CD3. Cytoplasmic CD3 zeta was present in almost all fresh CD3- DGL, whereas CD3 epsilon was not. Most DGL clones did not express surface Fc gamma receptors I-III (CD64, -32 and -16, respectively) and complement receptors (CR) types 1 and 2 (CD35 and 21, respectively), but 43% expressed CR3 (CD11b/18); in contrast, all PBNK clones were CR3+. The NK cell-associated molecules Kp43 (CD94) and the p58 molecule recognized by the HP3E4 monoclonal antibody were both present on a higher proportion of CD3- PBNK (91% and 50%, respectively) than DGL clones (31% and 14%, respectively), despite expression of CD94 by > 90% of fresh CD56+ decidual leucocytes. Five of 35 CD3- DGL clones expressed cytoplasmic CD3 zeta in the absence of expression of CD2, CD16 or the p58 molecule recognized by HP3E4. These variations between CD3- DGL and PBNK cell clones in expression of functional molecules may be related to previously reported differences in major histocompatibility complex-non-restricted cytotoxic activities between these two cell types.

Antigens, Surface↗
PubMed1995

Decidual-trophoblast interactions: decidual lymphoid cell populations in basal and parietal decidua.

Immunohistochemical analysis of tissue specimens from human pregnancy decidua basalis in contact with invasive trophoblast of chorion frondosum and decidua parietalis in contact with non-invasive chorion laeve do not differ in the frequency of lymphoid cells of the following phenotypes (CD2, CD4, CD8, CD14, CD21 and gamma/delta TCR). A practical implication of this observation is that the collection of lymphoid cells from whole decidua by curettage for functional studies is justified.

Antigens, CD↗
PubMed1995

Characteristics of perforin expressing lymphocytes within the first trimester decidua of human pregnancy.

PROBLEM: The number of perforin (P)-positive cells in decidua of pregnancy is larger than that observed in any other pathological condition. The aim was to investigate the distribution and the phenotype of P+ cells. METHOD: Decidual tissue was obtained from the first trimester vaginal termination of pregnancy. Tissue distribution of P+ cells was analyzed by immunohistochemistry. The method for simultaneous measurement of P and cell surface is presented. RESULTS: There is no difference in number and distribution of P+ cells between decidua basalis (DB) and decidua parietalis (DP). The percentage of P+ decidual lymphocytes (DL) is two times higher than in peripheral blood lymphocytes (PBL) (55% vs. 27%), and the prevalent phenotype is CD3- CD4- CD8- CD2+ (95%) CD11c+ (68%) and CD56+ (82%). CD56bright+ DL are also Pbright+ and this is the largest DL subpopulation (42.4% DL). Two different subpopulations of CD8+ DL exist: 1) CD8bright+, which are CD3+ CD56- P- and 2) CD8dim+, which are CD3- CD56+ P+. CONCLUSION: P expressing DL are prevalently nonclassical NK cells (CD16-) with low cytolytic activity but fully equipped with potent cytolytic machinery (Pbright+). There are no classical cytotoxic lymphocytes (CTL) (CD3+ CD8+ P+) in the decidua, and all CD8+ P+ cells are CD3- CD56+. The number of P+ cells is even higher in DP in the vicinity of noninvasive trophoblast, than in DB.

Biomarkers↗
PubMed1995

Immunoregulating effects of peptidoglycan monomer linked with zinc in adult mice.

Since it is well known that both zinc ions and bacterial immunostimulants influence the function of the immune system, in the present study we investigated the immunomodulating activity of a new analog of peptidoglycan monomer (PGM), in which the basic molecule was linked to zinc (PGM-Zn). Its effects in BALB/c mice, aged 10-12 months, were compared with the effects of equimolar doses of PGM and ZnCl2. The treatment lasted 26 days (one i.p. injection every fifth day). The results showed that PGM-Zn may markedly enhance antibody production to sheep red blood cells, as well as spontaneous and concanavalin A (ConA)-induced blastogenesis. The generation of plaque-forming cells in individual mouse was positively correlated with the expression of class II antigens in the liver and negatively correlated with the total quantity of hepatic proteins. PGM-Zn also induced the appearance of peritoneal macrophages, which in cocultures with syngeneic splenocytes were less able to enhance the spontaneous, and particularly the ConA-induced blastic transformation. The enhancing activities of PGM-Zn were in some respects more closely correlated with the action of PGM, whereas the induction of suppressive macrophages resembled more the activity of ZnCl2. The data emphasize that PGM-Zn may both stimulate and inhibit immunoregulative pathways by mechanisms which are not identical to those of PGM or ZnCl2.

Acetylmuramyl-Alanyl-Isoglutamine↗
PubMed1995

Immunosuppressive and antiproliferative effects of somatostatin analog SMS 201-995.

The effects of long acting somatostatin analog SMS 201-995 were examined in vivo on: 1) lymphoid morphostasis and functional reactivity of cells obtained from SMS treated donors, 2) on humoral, and 3) cellular type of immunity; and in vitro on: 1) blastic transformation of lymphocytes stimulated by activators of different transmembrane pathways (CD2 by PHA and CD3/TCR by anti-CD3 monoclonal antibody and by allogeneic cells) and 2) on growth and secretory activity of several hybridoma cell lines. The data have shown that SMS in vivo decreases the proportion of CD4+, CD5+ and Ig+ cells in spleen. The reactivity of these cells to Con A was suppressed, but their spontaneous blastic transformation was increased. SMS suppressed also the plaque forming cells generation and proliferation of cells in popliteal lymph nodes during the local host versus graft reaction. The former immunosuppression was abrogated with the use of growth hormone, while in the latter, the time dependent changes in spleen composition were also noticed. The data obtained in vitro revealed that SMS may inhibit only the CD2-induced blastogenesis (in early and late interval after the use of PHA). SMS inhibited also the spontaneous growth and/or secretion of antibodies in some hybridoma cell lines.

Animals↗
PubMed1994

Decidual-trophoblast interactions: decidual lymphoid cell function in normal, anembryonic, missed abortion and ectopic human pregnancy.

This study was designed to investigate the consequences of decidua-trophoblast interactions on the phenotype, spontaneous and induced proliferation and immunoregulatory potential of decidual leukocytes in normal pregnancies (NP), anembryonic pregnancies (AP), missed abortions (MA) and ectopic pregnancies (EP). Spontaneous proliferation of decidual non-adherent cells (NAD) from pregnancies with viable trophoblast inside the uterus is significantly higher than proliferation of peripheral blood lymphocytes (PBL) from the same groups (P < 0.001 for NP; P < 0.05 for AP). Spontaneous proliferation of decidual NAD cells from NP was higher (P < 0.001) when compared with AP and EP. The induced (PHA and Con A) responses of PBL from women with normal and pathological pregnancies were significantly higher than that of decidual NAD cells (P < 0.001). Higher proliferation of NAD decidual cells was obtained when Con A-stimulated NP were compared with MA and EP (P < 0.01). The interaction of viable trophoblast with intrauterine decidua appears to be a prerequisite for the activation of NAD suppressor cells, since NAD cells from MA produced stimulation instead of suppression, and NAD cells from EP had no suppressive effect. On the contrary, both NAD and adherent (AD) decidual leukocytes from NP and AP produced very strong suppression of PHA or alloantigen-induced PBL proliferation. The contact between trophoblast and AD decidual leukocytes is not necessary for their suppressive function, since even higher suppression is obtained with the cells from ectopic pregnancies.

Abortion, Missed↗
PubMed1993

An immunohistochemical study of leucocytes in human endometrium, first and third trimester basal decidua.

An immunohistochemical quantitative study of leucocyte subpopulations on fresh human endometrium and on biopsy specimens of first and third trimester basal decidua in normal (uncomplicated) pregnancies was performed. The most prominent population in endometrial and decidual stroma of basal decidua are macrophages. B cells as well as gamma/delta T cell receptor positive cells were found occasionally, scattered throughout the endometrial/decidual stroma. CD3+ cells were present in a relatively small number in the endometrium as well as in the first trimester basal decidua, but their number was elevated (doubled) in the third trimester of pregnancy. CD2+ cells showed a slight increase in first trimester basal decidua when compared with both endometrium and third trimester basal decidua. Cells with positive NKH-1 marker (CD56+) showed a significant increase in the first trimester, while in the third trimester their number diminished drastically. CD56:CD3 cell ratio increased to more than five times in first trimester basal decidua, while in the third trimester basal decidua decreased drastically. The mentioned increase of CD56+ cells in the first trimester and that of CD3+ cells at term suggests that these cells could have some specific function(s). However, it still has to be established whether the described quantitative changes of decidual leucocytes in basal decidua during pregnancy are of any importance for the mechanism(s) for the fetal allograft protection.

Antigens, CD↗
PubMed1991

Somatostatin promotes accumulation of phospholipids in regenerating liver tissue of rats.

Effects of somatostatin (SOM) on tissue contents of proteins, total lipids and phospholipids were investigated in regenerating and intact liver tissue of Y-59 rats. Whereas SOM inhibited protein accumulation in regenerating liver, the hormone evoked an increase in total lipids, and specially in phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine (PS) and phosphatidylinositol (PI). Since the same effects were not seen when intact liver was analyzed, it is assumed that SOM acts primarily on tissue stimulated to rapid growth. The increase of PS + PI fractions indicates a specific effect of SOM on the metabolism of phosphatidylinositides. Such an effect might result from the interference of the hormone with the action of growth factors that accelerate phosphatidylinositol breakdown.

Animals↗