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D Rukavina

Publications and source records attributed to D Rukavina.

At least 55 records · Page 3Linked to original sources
PubMed1991

Kinetics of lymphoproliferative responses of lymphocytes harvested from the uterine draining lymph nodes during pregnancy in rats.

Paraaortic lymph node (PALN) cells were harvested from virgin and pregnant rats bearing syngeneic or allogeneic fetuses at all stages of pregnancy including the pre-implantation period. The specific and non-specific alloreactivity of these cells was analyzed in mixed lymphocyte reactivity (MLR) against mitomycin-C treated-paternal strain or unrelated cells. Mitogen stimulation of the cell utilized PHA, Con-A and PWM. Cells bearing T cell markers were labeled in an indirect assay using the monoclonal antibodies W3/25 and MRC OX 8. Specific alloreactivity is strongly suppressed in the pre-implantation and implantation stages of pregnancy. Specific and non-specific alloreactivities were enhanced at mid-pregnancy and normalized by the end of pregnancy. Reactivity to polyclonal mitogens is enhanced at mid-pregnancy, and the CD4+/CD8+ ratio is very low during all phases of pregnancy.

Animals↗
PubMed1991

Reactivity to alloantigens and polyclonal mitogens and CD4+/CD8+ cell ratio shifts of cervical lymph node and spleen cells during pregnancy in rats.

Cervical lymph node (CLN) cells and spleen cells were harvested from virgin and pregnant rats bearing syngeneic or allogeneic fetuses at all stages of pregnancy including the pre-implantation period. The specific and non-specific alloreactivity of these cells were analyzed in MLR against mitomycin-C treated paternal strain or unrelated cells. Mitogen stimulation of the cell cultures utilized PHA, Con-A and PWM. Cells bearing T cell markers were labeled in an indirect assay using the monoclonal antibodies W3/25 and MRC OX 8. Specific alloreactivity is enhanced at mid-pregnancy in both cell populations. Non-specific alloreactivity was suppressed in the cervical lymph node cells. Spleen cells demonstrated an increased non-specific alloreactivity and T polyclonal mitogen reactivity (PHA and Con-A) at mid-pregnancy. Reactivity to Con-A was depressed in the early phase and at the end of allogeneic pregnancy in the CLN. The CD4+/CD8+ ratio was very low during all phases of pregnancy.

Animals↗
PubMed1991

Immunoregulatory factors contributing to fetal allograft survival.

A mammalian fetus expresses a variety of antigens potentially unknown to the immunologically competent mother. Presented here are the results of investigations of maternal immune reactivity to paternally derived antigens of fetoplacental unit, detected at various levels: 1) spleen and distant lymphatic organs, 2) regional lymph nodes draining uterus, and 3) materno-fetal interface. The results suggest that the mother's immune system reacts differently in semiallogeneic pregnancies than in syngeneic ones. The type of the systemic immune response depends on the stage of pregnancy. Increased percentage of CD8+ cells and decreased CD4+/CD8+ cell ratio was found in distant and regional lymphatic organs during pregnancy. The paternal class I MHC antigens expressed on the trophoblast cells are nonpolymorphic molecules which can have a role in immunotrophism of the placenta and in fetal allograft protection.

Animals↗
PubMed1990

Cells adherent to copper-bearing intrauterine contraceptive devices determined by monoclonal antibodies.

The presence of nucleated cells adherent to copper-bearing IUDs removed from successful IUD users, as well as from those IUD users with accidental pregnancy, was determined by a panel of monoclonal antibodies. A significant decrease in the percentage of CD3+ cells-mature T lymphocytes was found in the cell population adherent to IUDs removed from pregnant compared to non-pregnant uteri (43 +/- 2.6 vs 34 +/- 1.5). Among these cells, the percentage of CD4+ cells was increased (from 22.9 +/- 1.9 to 30.4 +/- 2.0), and CD8+ was decreased (from 23 +/- 0.9 to 10.8 +/- 1.2). The percentage of HLA-DR+ cells was also decreased (from 24.3 +/- 1.7 to 16.7 +/- 1.8). B4+ cells (B lymphocytes) were present in a similar percentage on IUDs removed from pregnant as well as from non-pregnant uteri. Thus, the uterine cavity in the presence of an IUD, contains a consistent population of immunologically competent cells. The question still remains, whether the change in the number of nucleated cells present in the uterine cavity with an IUD could contribute to its antifertility effect.

Adhesiveness↗
PubMed1990

Efficacious control of cytomegalovirus infection after long-term depletion of CD8+ T lymphocytes.

Although the relative contribution of different immune effector functions to clearing tissues of cytomegalovirus is controversial, the contribution of CD8+ T lymphocytes has generally been accepted as essential. In this report, we show that under certain conditions the CD8+ T-lymphocyte subset can be dispensable for clearance of cytomegalovirus. Mice depleted of the CD8+ T-lymphocyte subset eliminated infectious virus with a clearance kinetics similar to that of normal mice. Adoptive transfer studies revealed that the limitation of virus spread required the cooperation between the CD4+ subset and other cells. Comparison between protective functions generated in fully immunocompetent and in CD8- mice demonstrated that elimination of the CD8+ subset before infection altered the quality of the antiviral immune response. The compensatory protective activity gained by CD4+ cells in CD8- mice was absent in normal mice recovering from virus infection.

Animals↗
PubMed1990

Immunological observations in Guillain-Barré syndrome.

The results of some immunological analyses in 12 patients with the acute Guillain-Barré syndrome (GBS) are presented. The mean cerebrospinal fluid (CSF) concentrations of IgG and IgA were significantly increased. A longitudinal study of CSF IgG concentrations in 5 patients shows that the recovery period of the disease is not regularly accompanied by a decline of the IgG level. The finding of significantly reduced percentages of active T cells in the peripheral blood of patients with the acute GBS in comparison with the controls supports the view of the cellular immunity role in the pathogenesis of the disease. With the exception of HLA--B5 and HLA--B15, no other individual antigen was significantly more present in either the cases or controls.

Adolescent↗
PubMed1989

Growth of allogeneic sarcoma in mice subjected to halothane anesthesia and/or surgical stress.

The present study was designed to clarify mechanisms involved in suppression of cell-mediated immunity reported in patients undergoing major surgery with general anesthesia by determining the effects of halothane anesthesia with and without surgery on the growth of Sarcoma I (Sa I), a tumor allogeneic to BALB/c mice. Mice were given subcutaneous injections of 5 X 10(6) tumor cells from A/Jax mice and then immediately exposed to 0.5%-1.0% halothane for 1 hr without surgery (n = 7) or with surgery (midline laparotomy; n = 12). In control groups mice were also injected with tumor cells but were not exposed to prolonged halothane anesthesia. Some of them received only Sa I (n = 6), while the rest (n = 7) were also laparotomized. The rejection time of Sa I in mice exposed to halothane anesthesia was significantly longer (15.4 +/- 1.25 days) than in untreated controls (12.0 +/- 0.68 days) (P less than 0.05). In the mice exposed to halothane tumor growth was also greater. Surgical stress per se did not significantly affect growth or rejection time of Sa I (11.0 +/- 0.66 vs 12.0 +/- 0.68 days). Similarly, the combination of surgical stress with halothane anesthesia did not affect the immunosuppression associated with halothane alone (12.9 +/- 1.3 vs 15.4 +/- 1.25; P less than 0.05). The results indicate that halothane anesthesia per se may be associated with impairment of cell-mediated immunity under experimental conditions.

Anesthesia, Inhalation↗
PubMed1987

Alterations in immunological reactivity during pregnancy in mice determined in vitro by lymphoproliferation tests.

Primiparous and multiparous mice, either syngeneically or allogeneically pregnant, were sacrificed at various stages of pregnancy, and the immune reactivity of cells from different lymphatic organs was analyzed by mixed lymphocyte reaction (MLR) and concanavalin A (Con A)-induced lymphocyte proliferation. In the MLR, spleen cells and cells from the axillary lymph nodes of pregnant animals showed similar changes in their response to allogeneic cells during the course of gestation. In comparison to age-matched virgin controls they had an increased reactivity between the 7th and 11th day of pregnancy. During the preimplantation period and the last week of pregnancy, their alloreactivity was comparable to that of the controls. Cells from the para-aortic lymph nodes, which drain the uterus, also showed an increased reactivity at mid-gestation, but in the preimplantation period and third week of pregnancy their alloreactivity was even decreased in comparison to the control animals. When T cell immunocompetence was measured by means of lymphocyte transformation induced with Con A, the pattern of reactivity was completely different. Lymphoid cells from all the above-mentioned tissues showed the highest response to Con A during the preimplantation period, constantly weakening towards term.

Animals↗
PubMed1987

Distribution of T-lymphocyte subsets in porcine lymphoid tissues.

The distribution of the functional subsets of porcine T cells, the cytolytic/suppressor (Tc/s) and the helper/inducer (Th/i) cells was studied in cryostat sections of thymus, lymph nodes, tonsils, Peyer's patches, spleen and liver using the indirect immunoperoxidase technique. Three murine monoclonal antibodies (mAb) were used. The mAb 8/1 reacts with an antigen present on all T cells and on cells of the myeloid lineage; the antigen has not yet been characterized biochemically. The mAb 295/33 (anti-T8) binds to the porcine T8 antigen and defines the Tc/s subset, while mAb PT-4 (anti-T4) detects the porcine T4 antigen and defines the Th/i subset. Practically all thymocytes were stained by mAb 8/1. The majority of cortical thymocytes apparently co-expressed T8 and T4, whereas distinct fractions of medullary cells were labelled by either anti-T8 or anti-T4. In peripheral lymphoid organs all three mAb reacted with cells in the thymus-dependent areas and with cells scattered in the lymphoid follicles. In lymph nodes, tonsils and Peyer's patches, anti-T8 and anti-T4 each labelled approximately half of the cells stained by mAb 8/1. In the periarteriolar lymphoid sheath of the spleen, anti-T4 labelled more cells than did anti-T8. The reactivity of mAb 8/1 with the Kupffer cells of the liver demonstrated the expression of the 8/1 antigen on cells of the monocyte lineage. The T8 and T4 antigens could not be detected in acetone-fixed and paraffin-embedded sections, while the antigen recognized by mAb 8/1 remained preserved. Altogether, despite an inverted microanatomical structure of porcine lymph nodes, the frequency and distribution of T8+ and T4+ cells in thymus-dependent areas proved to be similar to those found in other species.

Animals↗
PubMed1986

Immune responsiveness in offspring of adoptively immunized mothers.

The rate of appearance of cells forming 19S hemolytic antibody (PFC) in the spleens of F1 newborn mice after adoptive anti-paternal immunization of fetuses, newborns and/or their mothers during pregnancy has been studied. An increase in the number of PFC was found at the age of 6 to 11 days in offspring of adoptively immunized mothers. These newborns, even when foster nursed by untreated mothers, still had a significantly higher number of PFC in comparison to the controls. In contrast, adoptive immunization of the newborns themselves resulted in a decrease of PFC during the second week after birth. Several possible explanations for the obtained results are discussed including the putative transplacental passage of immunocompetent cells.

Animals↗