scholarly journals The Effect of Microtubule Stabilising Drugs on Immune-Mediated Excytosis

2021 ◽  
Author(s):  
◽  
Marcus James Robinson
Keyword(s):  
Protein Transport ◽  
Dynamic Balance ◽  
Cytotoxic T Cells ◽  
Inhibitory Effect ◽  
Target Cells ◽  
Immunomodulatory Effects ◽  
Microtubule Network ◽  
Immune Mediated

<p>The microtubule network is involved in cellular processes including protein transport and cell division. Microtubule stabilising drugs (MSD) bind to microtubules and alter their dynamic balance in favour of the polymerised state. While primarily known for their anti-mitotic properties, MSD also exert immunomodulatory effects in vitro and in vivo. It is the aim of this project to investigate the effects of MSD on protein trafficking and secretion to determine how they affect immune-mediated exocytosis. Previous work in our lab demonstrated that macrophage responses to bacterial lipopolysaccharide, as measured by the production of TNF-a and nitric oxide, are inhibited by both paclitaxel and peloruside. In this thesis we continued this work and saw that inhibition was not affected by temporal IFN-y priming and found that altered production kinetics were not sufficient to explain the inhibition. To kill target cells cytotoxic T cells (CTL) reorganise their cytoskeleton so that lytic granules can traffic down microtubules to be delivered to the target. Using an in vitro model of CTL killing, we saw that MSD did not inhibit killing by CTL, lytic granule delivery to the cell surface, or antigen-stimulated Interferon-y (IFN-y) production by CTL. In contrast to this, in a murine model of antigen-induced killing we saw that a single dose of paclitaxel had a significant inhibitory effect on CTL-mediated cytolysis in vivo. Together these studies suggest that MSD have multiple immunomodulatory effects that are independent of their anti-proliferative effects. The data suggest that patients undergoing taxane therapy may be unable to fight infection long before the anti-mitotic effects of MSD are apparent.</p>

scholarly journals The Effect of Microtubule Stabilising Drugs on Immune-Mediated Excytosis

2021 ◽  
Author(s):  
◽  
Marcus James Robinson
Keyword(s):  
Protein Transport ◽  
Dynamic Balance ◽  
Cytotoxic T Cells ◽  
Inhibitory Effect ◽  
Target Cells ◽  
Immunomodulatory Effects ◽  
Microtubule Network ◽  
Immune Mediated

<p>The microtubule network is involved in cellular processes including protein transport and cell division. Microtubule stabilising drugs (MSD) bind to microtubules and alter their dynamic balance in favour of the polymerised state. While primarily known for their anti-mitotic properties, MSD also exert immunomodulatory effects in vitro and in vivo. It is the aim of this project to investigate the effects of MSD on protein trafficking and secretion to determine how they affect immune-mediated exocytosis. Previous work in our lab demonstrated that macrophage responses to bacterial lipopolysaccharide, as measured by the production of TNF-a and nitric oxide, are inhibited by both paclitaxel and peloruside. In this thesis we continued this work and saw that inhibition was not affected by temporal IFN-y priming and found that altered production kinetics were not sufficient to explain the inhibition. To kill target cells cytotoxic T cells (CTL) reorganise their cytoskeleton so that lytic granules can traffic down microtubules to be delivered to the target. Using an in vitro model of CTL killing, we saw that MSD did not inhibit killing by CTL, lytic granule delivery to the cell surface, or antigen-stimulated Interferon-y (IFN-y) production by CTL. In contrast to this, in a murine model of antigen-induced killing we saw that a single dose of paclitaxel had a significant inhibitory effect on CTL-mediated cytolysis in vivo. Together these studies suggest that MSD have multiple immunomodulatory effects that are independent of their anti-proliferative effects. The data suggest that patients undergoing taxane therapy may be unable to fight infection long before the anti-mitotic effects of MSD are apparent.</p>

scholarly journals The influenza A virus nucleoprotein gene controls the induction of both subtype specific and cross-reactive cytotoxic T cells.

1984 ◽  
Vol 160 (2) ◽  
pp. 552-563 ◽  
Author(s):  
A R Townsend ◽  
J J Skehel
Keyword(s):  
T Cells ◽  
Influenza A ◽  
Cytotoxic T Cells ◽  
Target Cells ◽  
Spleen Cells ◽  
Influenza A Viruses ◽  
Group A ◽  
Selection Of

Using genetically typed recombinant influenza A viruses that differ only in their genes for nucleoprotein, we have demonstrated that repeated stimulation in vitro of C57BL/6 spleen cells primed in vivo with E61-13-H17 (H3N2) virus results in the selection of a population of cytotoxic T lymphocytes (CTL) whose recognition of infected target cells maps to the gene for nucleoprotein of the 1968 virus. Influenza A viruses isolated between 1934 and 1979 fall into two groups defined by their ability to sensitize target cells for lysis by these CTL: 1934-1943 form one group (A/PR/8/34 related) and 1946-1979 form the second group (A/HK/8/68 related). These findings complement and extend our previous results with an isolated CTL clone with specificity for the 1934 nucleoprotein (27, 28). It is also shown that the same spleen cells derived from mice primed with E61-13-H17 virus in vivo, but maintained in identical conditions by stimulation with X31 virus (which differs from the former only in the origin of its gene for NP) in vitro, results in the selection of CTL that cross-react on target cells infected with A/PR/8/1934 (H1N1) or A/Aichi/1968 (H3N2). These results show that the influenza A virus gene for NP can play a role in selecting CTL with different specificities and implicate the NP molecule as a candidate for a target structure recognized by both subtype-directed and cross-reactive influenza A-specific cytotoxic T cells.

scholarly journals REJECTION OF TUMOR ALLOGRAFTS BY MOUSE SPLEEN CELLS SENSITIZED IN VITRO

1971 ◽  
Vol 133 (4) ◽  
pp. 821-833 ◽  
Author(s):  
Irun R. Cohen ◽  
Amiela Globerson ◽  
Michael Feldman
Keyword(s):  
Inhibitory Effect ◽  
Lymphoid Cells ◽  
Mouse Spleen ◽  
Target Cells ◽  
Functional Assay ◽  
Spleen Cells ◽  
Growth Of Tumor ◽  
Selection Of

This paper reports a model system of cellular immunity in which allosensitization of mouse spleen cells is induced in vitro. Allosensitization was achieved by culturing spleen cells upon monolayers of allogeneic fibroblasts. The ability of the spleen cells to inhibit the growth of tumor allografts in vivo served as a functional assay of sensitization. We found that unsensitized spleen cells or spleen cells sensitized against unrelated fibroblast antigens had no inhibitory effect on the growth of allogeneic fibrosarcoma cells when they were injected together into irradiated recipients. In contrast, spleen cells which were specifically allosensitized in vitro were found to be highly effective in inhibiting the growth of an equal number of allogeneic tumor cells. Several times more spleen cells from mice sensitized in vivo were required to produce a similar immune effect. This confirms the findings of previous studies which indicate that sensitization in cell culture can promote the selection of specifically sensitized lymphocytes. Preincubating sensitizing fibroblasts with allo-antisera blocked the allosensitization of spleen cells. This suggests that antibodies binding to fibroblasts may inhibit the induction of sensitization by competing with lymphocytes for antigenic sites. Mouse spleen cells which were able to recognize and reject tumor allografts in vivo were unable to cause lysis of target fibroblasts in vitro. Such fibroblasts, however, were susceptible to lysis by rat lymphoid cells sensitized by a similar in vitro method. These findings indicate that the conditions required for lymphocyte-mediated lysis of target cells may not be directly related to the processes of antigen recognition and allograft rejection in vivo.

Anti-leukemia activity of CD33-specific chimeric cytotoxic T lymphocytes in vitro and in vivo is impaired by addition of the CD28 costimulatory endodomain

2007 ◽  
Vol 25 (18_suppl) ◽  
pp. 3052-3052
Author(s):  
A. Dutour ◽  
D. Lee ◽  
S. Napier ◽  
E. Yvon ◽  
H. Finney ◽  
...  
Keyword(s):  
T Cells ◽  
Cytotoxic T Cells ◽  
Surface Protein ◽  
Receptor Expression ◽  
Target Cells ◽  
Chimeric Receptor ◽  
Specific Lysis ◽  
Significant Difference

3052 Background: EBV-specific cytotoxic T cells (EBV-CTLs) expand and have long-term activity in vivo due to the sustained costimulation provided by the EBV-infected cells produced by this persistent virus. We exploited this phenomenon and redirected EBV-CTLs against CD33, a surface protein expressed on the malignant blasts of acute myeloid leukemia (AML) cells. Methods: EBV-CTLs generated from six EBV-seropositive donors were transduced using a retroviral vector encoding CD33 specific chimeric receptor (cR). We evaluated whether the high and sustained activity shown against native EBV+ target cells can be extended to the CD33+ EBV- targets of the chimeric receptor and whether the addition of CD28 signaling domain improved the receptor activity. Results: cRCD33-EBV-CTL maintained killed EBV-LCL and CD33+ targets (specific lysis respectively of 30% and 35% at E:T ratio 25:1). They produced Th-1, Th-2 and Tc cytokines on exposure to CD33+ targets. Addition of the CD28 intracellular domain did not increase cytotoxicity to CD33+ targets. Preincubation of CD33+ cells with the CD33-blocking MoAb resulted in up to 40% inhibition of lysis and up to 60% inhibition of cytokine release by cRCD33-EBV-CTLs confirming the specificity of the TCR interactions with CD33. NOD-SCID mice bearing a human CD33+ AML were injected with EBV-CTLs ×4 weekly starting 5 days after tumor inoculation. Significant tumor reduction was only observed in mice treated with the cRCD33-EBV-CTLs (p<0.05). Immunohistologic analysis showed the presence of a majority of CD8+ human T cells in the tumors of treated mice. Incorporation of the CD28 endodomain resulted in less tumor-infiltrating T cells in mice treated with cRCD33CD28-EBV-CTLs. There was no significant difference in the chemokines receptor expression on cRCD33CD28-EBV-CTLs but their rate of apoptosis was 16 % higher (p<0.05) than the one of cRCD33-EBV-CTLs. Conclusions: EBV- CTL expressing the CD33 chimeric receptor are functional in vitro and in vivo in mice. CD28 signaling may have a deleterious role for the activity of chimeric receptors in vivo. No significant financial relationships to disclose.

scholarly journals Antiviral protection by virus-immune cytotoxic T cells: infected target cells are lysed before infectious virus progeny is assembled.

1977 ◽  
Vol 145 (3) ◽  
pp. 644-651 ◽  
Author(s):  
R M Zinkernagel ◽  
A Althage
Keyword(s):  
T Cells ◽  
Adoptive Transfer ◽  
Infectious Virus ◽  
Cytotoxic T Cells ◽  
Target Cells ◽  
Virus Infections ◽  
Virus Growth ◽  
Virus Progeny

Virus-immune cytotoxic T cells can inhibit effectively growth of vaccinia virus in acutely infected target cells in vitro by destroying infected target cells before infectious virus progeny is assembled. Together with the fact that virus-specific T cells are demonstrable after 3 days, very early during infection, and with strong circumstantial evidence from adoptive transfer models in vivo, these data suggest that in some virus infections T cells may in fact act cytolytically in vivo to prevent virus growth and spread and be an important early antiviral effector mechanism.

scholarly journals Joint recognition by cytotoxic T cells of inactivated Sendai virus and products of the major histocompatibility complex.

1977 ◽  
Vol 145 (3) ◽  
pp. 523-539 ◽  
Author(s):  
J W Schrader ◽  
G M Edelman
Keyword(s):  
T Cells ◽  
Sendai Virus ◽  
Cytotoxic T Cells ◽  
Secondary Response ◽  
Cytotoxic T Cell ◽  
Target Cells ◽  
Murine Spleen ◽  
Virion Antigen

Cytotoxic T cells specific for Sendai virus were generated by culturing murine spleen cells in vitro together with UV-inactivated Sendai virus. In vivo immunization of donor mice with UV-inactivated Sendai virus resulted in an in vitro secondary response of increased magnitude. Cytotoxic activity was demonstrated in a short-term 51Cr-release assay, using syngeneic tumor cells which had been coated with inactivated Sendai virus by incubation at 4 degrees C for 30 min. The lysis of Sendai virus-coated target cells was restricted by the H-2 haplotype of the target cells, suggesting that the H-2 genes of the target cell contributed to the specificity of the lysis. Kinetic experiments showed that susceptibility to lysis by cytotoxic T cells specific for Sendai virus appeared within 30 min after coating target cells with inactivated virus. Furthermore, there was no detectable synthesis of new proteins in cells treated with UV-inactivated Sendai virus. For these reasons, we suggest that neither viral replication nor the synthesis of new proteins are necessary for the production of the antigen recognized by cytotoxic cells specific for Sendai virus. We infer that the virus-specific component on the target cells is probably a preformed virion antigen adsorbed onto or integrated into the cell membrane. These results imply that, if the cytotoxic T cell recognizes a single antigenic determinant specified both by viral and H-2 genes, this determinant is formed by the physical association of H-2 and Sendai virus antigens rather than by their alteration during the processes of synthesis.

scholarly journals Cytotoxic T cells distinguish between trinitrophenyl- and dinitrophenyl-modified syngeneic cells.

1977 ◽  
Vol 146 (2) ◽  
pp. 600-605 ◽  
Author(s):  
J Forman
Keyword(s):  
T Cells ◽  
Cytotoxic Effect ◽  
Cytotoxic T Cells ◽  
Cytotoxic T Cell ◽  
Target Cells ◽  
Spleen Cells ◽  
Competition Assay ◽  
Effector Cells

Spleen cells sensitized against trinitrophenyl (TNP)-modified stimulator cells displayed a cytotoxic effect against syngeneic TNP-modified but not dinitrophenyl (DNP)-modified target cells. The same finding was observed in the opposite direction; that is, effector cells sensitized against DNP-modified stimulator cells did not cross kill TNP-modified targets. The specificity of the anti-TNP effector cells was confirmed in a cold target competition assay. Presensitization in vivo with hapten-modified cells followed by rechallenge and testing in vitro did not alter the specificity of the response between the haptens. These data indicate that the receptor(s) on the cytotoxic T cell can distinguish between two closely related haptenic molecules.

scholarly journals CD8+-Cell-Mediated Suppression of Virulent Simian Immunodeficiency Virus during Tenofovir Treatment

2004 ◽  
Vol 78 (10) ◽  
pp. 5324-5337 ◽  
Author(s):  
Koen K. A. Van Rompay ◽  
Raman P. Singh ◽  
Bapi Pahar ◽  
Donald L. Sodora ◽  
Casey Wingfield ◽  
...  
Keyword(s):  
Immune Responses ◽  
Simian Immunodeficiency Virus ◽  
Chronic Infection ◽  
Immunomodulatory Effects ◽  
In Vitro Susceptibility ◽  
Immune Mediated ◽  
Immunodeficiency Virus ◽  
Cd8 Cell

ABSTRACT The ability of tenofovir to suppress viremia in simian immunodeficiency virus (SIV)-infected macaques for years despite the presence of virulent viral mutants with reduced in vitro susceptibility is unprecedented in this animal model. In vivo cell depletion experiments demonstrate that tenofovir's ability to suppress viremia during acute and chronic infection is significantly dependent on the presence of CD8+ lymphocytes. Continuous tenofovir treatment was required to maintain low viremia. Although it is unclear whether this immune-mediated suppression of viremia is linked to tenofovir's direct antiviral efficacy or is due to independent immunomodulatory effects, these studies prove the concept that antiviral immune responses can play a crucial role in suppressing viremia during anti-human immunodeficiency virus drug therapy.

scholarly journals Depletion of the C3 component of complement enhances the ability of rituximab-coated target cells to activate human NK cells and improves the efficacy of monoclonal antibody therapy in an in vivo model

Blood ◽  
2009 ◽  
Vol 114 (26) ◽  
pp. 5322-5330 ◽  
Author(s):  
Siao-Yi Wang ◽  
Suresh Veeramani ◽  
Emilian Racila ◽  
Jeffrey Cagley ◽  
David C. Fritzinger ◽  
...  
Keyword(s):  
Monoclonal Antibody ◽  
Nk Cells ◽  
Cell Activation ◽  
Nk Cell ◽  
Antibody Therapy ◽  
Inhibitory Effect ◽  
In Vivo Model ◽  
Target Cells

Abstract Growing evidence indicates antibody-dependent cellular cytotoxicity (ADCC) contributes to the clinical response to monoclonal antibody (mAb) therapy of lymphoma. Recent in vitro analysis suggests C3b can inhibit mAb-induced natural killer (NK)–cell activation and ADCC. Further studies were conducted to assess the effect of C3 depletion on mAb-induced NK activation and therapy of lymphoma. Normal human serum inhibited the ability of rituximab-coated lymphoma cells to activate NK cells as previously reported. Serum did not inhibit NK-cell activation when it was preincubated with cobra venom factor (CVF) to deplete C3. Similar results were found when transudative pleural fluid or nonmalignant ascites was used as surrogates for extravascular fluid, suggesting the inhibitory effect of complement may be present in the extravascular compartment, in which many malignant lymphocytes reside. In vivo, C3 was depleted before mAb treatment in a syngeneic murine model of lymphoma. Survival of lymphoma-bearing mice after treatment with CVF plus mAb and with a human C3 derivative with CVF-like functions (HC3-1496) plus mAb was both superior to that of mAb alone. These studies show that complement depletion enhances NK-cell activation induced by rituximab-coated target cells and improves the efficacy of mAb therapy in a murine lymphoma model.

The Effect of Barbituric Acid Derivatives on Platelet Function in Vitro and in Vivo

1973 ◽  
Vol 30 (02) ◽  
pp. 315-326
Author(s):  
J. Heinz Joist ◽  
Jean-Pierre Cazenave ◽  
J. Fraser Mustard
Keyword(s):  
Platelet Aggregation ◽  
Platelet Function ◽  
Barbituric Acid ◽  
Platelet Rich Plasma ◽  
Inhibitory Effect ◽  
Primary Response ◽  
Sodium Pentobarbital ◽  
Barbituric Acid Derivatives

SummarySodium pentobarbital (SPB) and three other barbituric acid derivatives were found to inhibit platelet function in vitro. SPB had no effect on the primary response to ADP of platelets in platelet-rich plasma (PRP) or washed platelets but inhibited secondary aggregation induced by ADP in human PRP. The drug inhibited both phases of aggregation induced by epinephrine. SPB suppressed aggregation and the release reaction induced by collagen or low concentrations of thrombin, and platelet adherence to collagen-coated glass tubes. The inhibition by SPB of platelet aggregation was readily reversible and isotopically labeled SPB did not become firmly bound to platelets. No inhibitory effect on platelet aggregation induced by ADP, collagen, or thrombin could be detected in PRP obtained from rabbits after induction of SPB-anesthesia.

Sign in / Sign up

Export Citation Format

Share Document