S Sad

Summary

Affiliation: National Research Council
Country: Canada

Publications

  1. ncbi request reprint Cytokine-deficient CD8+ Tc1 cells induced by IL-4: retained inflammation and perforin and Fas cytotoxicity but compromised long term killing of tumor cells
    S Sad
    Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Canada
    J Immunol 159:606-13. 1997
  2. pmc Caspase-3 is transiently activated without cell death during early antigen driven expansion of CD8(+) T cells in vivo
    Scott McComb
    Department of Biochemistry, NRC Institute for Biological Sciences, University of Ottawa, Ottawa, Canada
    PLoS ONE 5:e15328. 2010
  3. ncbi request reprint Maintenance and attrition of T-cell memory
    Subash Sad
    Institute for Biological Sciences, National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario, Canada
    Crit Rev Immunol 23:129-47. 2003
  4. ncbi request reprint Cytokine deprivation of naive CD8+ T cells promotes minimal cell cycling but maximal cytokine synthesis and autonomous proliferation subsequently: a mechanism of self-regulation
    S Sad
    Institute for Biological Sciences, National Research Council of Canada, Ottawa, Ontario
    J Immunol 163:2443-51. 1999
  5. ncbi request reprint Pathogen proliferation governs the magnitude but compromises the function of CD8 T cells
    Subash Sad
    Institute for Biological Sciences, National Research Council of Canada, 1200 Montreal Road, Ottawa, Ontario, Canada
    J Immunol 180:5853-61. 2008
  6. ncbi request reprint Archaeosomes induce long-term CD8+ cytotoxic T cell response to entrapped soluble protein by the exogenous cytosolic pathway, in the absence of CD4+ T cell help
    L Krishnan
    Institute for Biological Sciences, National Research Council of Canada, Ottawa, Ontario, Canada
    J Immunol 165:5177-85. 2000
  7. ncbi request reprint Delayed expansion and contraction of CD8+ T cell response during infection with virulent Salmonella typhimurium
    Rachel A Luu
    Laboratory of Cellular Immunology, National Research Council Institute for Biological Sciences, Ontario, Canada
    J Immunol 177:1516-25. 2006
  8. ncbi request reprint The potent adjuvant activity of archaeosomes correlates to the recruitment and activation of macrophages and dendritic cells in vivo
    L Krishnan
    Institute for Biological Sciences, National Research Council of Canada, Ottawa, Ontario, Canada
    J Immunol 166:1885-93. 2001
  9. ncbi request reprint Phosphatidylserine receptor-mediated recognition of archaeosome adjuvant promotes endocytosis and MHC class I cross-presentation of the entrapped antigen by phagosome-to-cytosol transport and classical processing
    Komal Gurnani
    Institute for Biological Sciences, National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario, Canada K1A 0R6
    J Immunol 173:566-78. 2004
  10. pmc IL-10 produced by trophoblast cells inhibits phagosome maturation leading to profound intracellular proliferation of Salmonella enterica Typhimurium
    T Nguyen
    Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, ON, Canada
    Placenta 34:765-74. 2013

Collaborators

Detail Information

Publications35

  1. ncbi request reprint Cytokine-deficient CD8+ Tc1 cells induced by IL-4: retained inflammation and perforin and Fas cytotoxicity but compromised long term killing of tumor cells
    S Sad
    Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Canada
    J Immunol 159:606-13. 1997
    ..These results suggest that IL-4 synthesis in vivo would not affect immediate effector functions of differentiated Tc1 cells, but would compromise immunity by reducing their long term functional capability...
  2. pmc Caspase-3 is transiently activated without cell death during early antigen driven expansion of CD8(+) T cells in vivo
    Scott McComb
    Department of Biochemistry, NRC Institute for Biological Sciences, University of Ottawa, Ottawa, Canada
    PLoS ONE 5:e15328. 2010
    ..Surprisingly, evidence has shown non-apoptotic activation of caspase-3 to occur during in vitro T-cell proliferation, but the relevance of these mechanisms to in vivo CD8(+) T cell responses has yet to be examined...
  3. ncbi request reprint Maintenance and attrition of T-cell memory
    Subash Sad
    Institute for Biological Sciences, National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario, Canada
    Crit Rev Immunol 23:129-47. 2003
    ..This review will primarily focus on the factors that influence the generation, maintenance, and attrition of memory CD8+ T cells...
  4. ncbi request reprint Cytokine deprivation of naive CD8+ T cells promotes minimal cell cycling but maximal cytokine synthesis and autonomous proliferation subsequently: a mechanism of self-regulation
    S Sad
    Institute for Biological Sciences, National Research Council of Canada, Ottawa, Ontario
    J Immunol 163:2443-51. 1999
    ..These results suggest that the presence of excessive IL-2 during the activation of naive CD8+ T cells, while promoting cell cycling initially, may compromise long-term immunity...
  5. ncbi request reprint Pathogen proliferation governs the magnitude but compromises the function of CD8 T cells
    Subash Sad
    Institute for Biological Sciences, National Research Council of Canada, 1200 Montreal Road, Ottawa, Ontario, Canada
    J Immunol 180:5853-61. 2008
    ..Taken together, these results indicate that pathogens that proliferate rapidly and chronically in vivo may evoke functionally inferior memory CD8+ T cells which may promote the survival of the pathogen...
  6. ncbi request reprint Archaeosomes induce long-term CD8+ cytotoxic T cell response to entrapped soluble protein by the exogenous cytosolic pathway, in the absence of CD4+ T cell help
    L Krishnan
    Institute for Biological Sciences, National Research Council of Canada, Ottawa, Ontario, Canada
    J Immunol 165:5177-85. 2000
    ..Thus, delivery of proteins in self-adjuvanting archaeosomes represents a novel strategy for targeting exogenous Ags to the MHC class I pathway for induction of CTL response...
  7. ncbi request reprint Delayed expansion and contraction of CD8+ T cell response during infection with virulent Salmonella typhimurium
    Rachel A Luu
    Laboratory of Cellular Immunology, National Research Council Institute for Biological Sciences, Ontario, Canada
    J Immunol 177:1516-25. 2006
    ..Thus, phagosomal lifestyle may allow escape from host CD8(+) T cell recognition, conferring a survival advantage to the pathogen...
  8. ncbi request reprint The potent adjuvant activity of archaeosomes correlates to the recruitment and activation of macrophages and dendritic cells in vivo
    L Krishnan
    Institute for Biological Sciences, National Research Council of Canada, Ottawa, Ontario, Canada
    J Immunol 166:1885-93. 2001
    ..Thus, the recruitment and activation of professional APCs by archaeosomes constitutes an efficient self-adjuvanting process for induction of Ag-specific responses to encapsulated Ags...
  9. ncbi request reprint Phosphatidylserine receptor-mediated recognition of archaeosome adjuvant promotes endocytosis and MHC class I cross-presentation of the entrapped antigen by phagosome-to-cytosol transport and classical processing
    Komal Gurnani
    Institute for Biological Sciences, National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario, Canada K1A 0R6
    J Immunol 173:566-78. 2004
    ..Our results reveal the novel ability of archaeosomes to exploit this mechanism for cytosolic MHC class I Ag processing, and provide an effective particulate vaccination strategy...
  10. pmc IL-10 produced by trophoblast cells inhibits phagosome maturation leading to profound intracellular proliferation of Salmonella enterica Typhimurium
    T Nguyen
    Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, University of Ottawa, ON, Canada
    Placenta 34:765-74. 2013
    ..Salmonella enterica Typhimurium (ST) is a phagosomal pathogen that can infect placental trophoblast cells leading to abortion and severe maternal illness. It is unclear how the trophoblast cells promote profound bacterial proliferation...
  11. ncbi request reprint Cytokine-induced differentiation of precursor mouse CD8+ T cells into cytotoxic CD8+ T cells secreting Th1 or Th2 cytokines
    S Sad
    Department of Immunology, University of Alberta, Edmonton, Canada
    Immunity 2:271-9. 1995
    ..We propose the names TC1 and TC2 for cytotoxic CD8+ T cells secreting Th1-like and Th2-like cytokines, respectively...
  12. ncbi request reprint Reducing the stimulation of CD8+ T cells during infection with intracellular bacteria promotes differentiation primarily into a central (CD62LhighCD44high) subset
    Henk van Faassen
    Laboratory of Cellular Immunology, Institute for Biological Sciences, National Research Council of Canada, Ottawa, Ontario, Canada
    J Immunol 174:5341-50. 2005
    ....
  13. ncbi request reprint The expanding universe of T-cell subsets: Th1, Th2 and more
    T R Mosmann
    Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Canada
    Immunol Today 17:138-46. 1996
    ....
  14. ncbi request reprint Archaeosomes induce enhanced cytotoxic T lymphocyte responses to entrapped soluble protein in the absence of interleukin 12 and protect against tumor challenge
    Lakshmi Krishnan
    Institute for Biological Sciences, National Research Council of Canada, Ottawa, Ontario, K1A 0R6 Canada
    Cancer Res 63:2526-34. 2003
    ..Thus, archaeosomes represent effective tumor antigen delivery vehicles that can mediate protection by activating both innate as well as acquired immunity...
  15. doi request reprint IFN-gamma expressed by T cells regulates the persistence of antigen presentation by limiting the survival of dendritic cells
    Marsha S Russell
    National Research Council Institute for Biological Sciences, University of Ottawa, Ottawa, Ontario, Canada
    J Immunol 183:7710-8. 2009
    ..These results reveal a novel mechanism indicating how IFN-gamma prevents the persistence of Ag presentation, thereby preventing memory T cells from going into exhaustion...
  16. ncbi request reprint Selectively reduced intracellular proliferation of Salmonella enterica serovar typhimurium within APCs limits antigen presentation and development of a rapid CD8 T cell response
    Homam Albaghdadi
    National Research Council Institute for Biological Sciences, Ottawa, Ontario, Canada
    J Immunol 183:3778-87. 2009
    ..monocytogenes. Taken together, this study reveals a dichotomy in the proliferation of ST and indicates that selectively reduced intracellular proliferation of virulent pathogens may be an important mechanism of immune evasion...
  17. doi request reprint Intracellular bacterial vectors that induce CD8(+) T cells with similar cytolytic abilities but disparate memory phenotypes provide contrasting tumor protection
    Felicity C Stark
    Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada
    Cancer Res 69:4327-34. 2009
    ..Thus, for efficacy, cancer vaccines should be selected for their ability to induce self-renewing memory CD8(+) T cells (CD44(high)IL-7Ralpha(high)CD62L(high)) besides their effector functions...
  18. ncbi request reprint A reduced antigen load in vivo, rather than weak inflammation, causes a substantial delay in CD8+ T cell priming against Mycobacterium bovis (bacillus Calmette-Guérin)
    Marsha S Russell
    National Research Council Institute for Biological Sciences, University of Ottawa, 1200 Montreal Road, Ottawa, Ontario, Canada
    J Immunol 179:211-20. 2007
    ....
  19. pmc Archaeosomes varying in lipid composition differ in receptor-mediated endocytosis and differentially adjuvant immune responses to entrapped antigen
    G Dennis Sprott
    Institute for Biological Sciences, National Research Council, 100 Sussex Drive, Ottawa, Ontario, Canada K1A 0R6
    Archaea 1:151-64. 2003
    ..morrhuae 14039 archaeosomes was striking compared with cells exposed to archaeosomes from 16008. Thus, archaeosome types uniquely modulate antigen delivery and dendritic cell activation...
  20. ncbi request reprint Increased CD8+ T cell memory to concurrent infection at the expense of increased erosion of pre-existing memory: the paradoxical role of IL-15
    Yvan Chapdelaine
    Laboratory of Cellular Immunology, Institute for Biological Sciences, National Research Council of Canada, Ontario, Canada
    J Immunol 171:5454-60. 2003
    ..We thus raise important questions regarding vaccinations that are aimed at maximizing T cell memory without considering the impact on pre-existing T cell memory...
  21. pmc Activation of dendritic cells by liposomes prepared from phosphatidylinositol mannosides from Mycobacterium bovis bacillus Calmette-Guerin and adjuvant activity in vivo
    G Dennis Sprott
    Institute for Biological Sciences, National Research Council, 100 Sussex Dr, Ottawa, Ontario K1A 0R6, Canada
    Infect Immun 72:5235-46. 2004
    ..Thus, the inclusion of pure phosphatidylinositol mannosides of BCG in lipid vesicle vaccines represents a simple and efficient option for targeting antigen delivery and providing immune stimulation...
  22. ncbi request reprint Rapid clonal expansion and prolonged maintenance of memory CD8+ T cells of the effector (CD44highCD62Llow) and central (CD44highCD62Lhigh) phenotype by an archaeosome adjuvant independent of TLR2
    Lakshmi Krishnan
    National Research Council Institute for Biological Sciences, Ottawa, Ontario, Canada
    J Immunol 178:2396-406. 2007
    ..Thus, an archaeosome adjuvant vaccine represents an alternative to live vectors for inducing CD8(+) T cell memory...
  23. ncbi request reprint Prolonged antigen presentation, APC-, and CD8+ T cell turnover during mycobacterial infection: comparison with Listeria monocytogenes
    Henk van Faassen
    Laboratory of Cellular Immunology, Institute for Biological Sciences, National Research Council of Canada, Ottawa, Ontario, Canada
    J Immunol 172:3491-500. 2004
    ..Relative to LM-OVA, the dendritic cells in BCG-OVA-infected mice were apoptotic for prolonged periods, suggesting that the rapid death of APCs may limit the magnitude of Ag presentation during chronic stages of mycobacterial infection...
  24. ncbi request reprint Multiple mechanisms compensate to enhance tumor-protective CD8(+) T cell response in the long-term despite poor CD8(+) T cell priming initially: comparison between an acute versus a chronic intracellular bacterium expressing a model antigen
    Renu Dudani
    Laboratory of Cellular Immunology, Institute for Biological Sciences, National Research Council, Ottawa, Ontario, Canada
    J Immunol 168:5737-45. 2002
    ..Despite a stronger initial T cell response with LM-OVA, BCG-OVA provided more effective tumor (B16OVA) control at both local and distal sites due to the induction of a persistently activated acquired, and a more potent innate, immunity...
  25. ncbi request reprint IFN-gamma induces the erosion of preexisting CD8 T cell memory during infection with a heterologous intracellular bacterium
    Renu Dudani
    National Research Council Institute for Biological Sciences, Ottawa, Ontario, Canada
    J Immunol 181:1700-9. 2008
    ..Although IFN-gamma promotes the control of intracellular bacterial replication during primary infection, this comes at the expense of erosion of preexisting memory CD8(+) T cells in the wake of infection with heterologous pathogens...
  26. ncbi request reprint Cross-reactive antigen is required to prevent erosion of established T cell memory and tumor immunity: a heterologous bacterial model of attrition
    Dean K Smith
    Laboratory of Cellular Immunology, Institute for Biological Sciences, National Research Council, Ottawa, Ontario, Canada
    J Immunol 169:1197-206. 2002
    ....
  27. pmc Preexisting inflammation due to Mycobacterium bovis BCG infection differentially modulates T-cell priming against a replicating or nonreplicating immunogen
    Renu Dudani
    Laboratory of Cellular Immunology, Institute for Biological Sciences, National Research Council, Ottawa, Ontario, Canada
    Infect Immun 70:1957-64. 2002
    ..monocytogenes-ovalbumin) was impaired. Thus, depending on the nature of the immunogen, the presence of prior inflammatory responses may either impede or boost vaccine efficacy...
  28. ncbi request reprint Mutation in the Fas pathway impairs CD8+ T cell memory
    Renu Dudani
    National Research Council of Canada, Institute for Biological Sciences, Ottawa, Ontario, Canada
    J Immunol 180:2933-41. 2008
    ..Thus, in individuals with mutation in Fas pathway, impairment in the function of the memory CD8+ T cells may increase their susceptibility to recurrent/latent infections...
  29. pmc cIAP1 and cIAP2 limit macrophage necroptosis by inhibiting Rip1 and Rip3 activation
    S McComb
    NRC Institute for Biological Sciences, Ottawa, Ontario, Canada
    Cell Death Differ 19:1791-801. 2012
    ..These results show that cIAPs have an important role in limiting programmed necrosis of macrophages, which facilitates effective control of a pathogen...
  30. ncbi request reprint Pregnancy impairs the innate immune resistance to Salmonella typhimurium leading to rapid fatal infection
    Branka Pejcic-Karapetrovic
    National Research Council Institute for Biological Sciences, Ottawa, Ontario, Canada
    J Immunol 179:6088-96. 2007
    ..Thus, highly virulent pathogens may use placental invasion to alter systemic host resistance to infection...
  31. pmc Mycobacterium bovis BCG-infected mice are more susceptible to staphylococcal enterotoxin B-mediated toxic shock than uninfected mice despite reduced in vitro splenocyte responses to superantigens
    Joao A Pedras-Vasconcelos
    Laboratory of Cellular Immunology, Institute for the Biological Sciences, National Research Council, Ottawa, Ontario, Canada
    Infect Immun 70:4148-57. 2002
    ..Our results indicate that the reported phenomena of T-cell anergy during mycobacterial infection may be an in vitro consequence of the development of a strong type 1 response in vivo...
  32. ncbi request reprint A novel role of IL-15 in early activation of memory CD8+ CTL after reinfection
    Toshiki Yajima
    Division of Host Defense, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Japan
    J Immunol 174:3590-7. 2005
    ..In vivo administration of rIL-15 conferred robust protection against reinfection via induction of granzyme B in the memory CD8+ T cells. These results suggest that IL-15 plays an important role in early activation of memory CD8+ T cells...
  33. ncbi request reprint Impaired protection against Mycobacterium bovis bacillus Calmette-Guerin infection in IL-15-deficient mice
    Kimika Saito
    Division of Host Defense, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Japan
    J Immunol 176:2496-504. 2006
    ..These results suggest that IL-15 plays an important role in the development of long-lasting protective immunity to BCG infection via sustaining CD8 responses in the lung...
  34. ncbi request reprint Apoptotic vesicles crossprime CD8 T cells and protect against tuberculosis
    Florian Winau
    Department of Immunology, Max Planck Institute for Infection Biology, Schumannstrasse 21 22, 10117 Berlin, Germany
    Immunity 24:105-17. 2006
    ..tuberculosis infection. Taken together, we propose the detour pathway to represent a genuine immunological mechanism mediating crosspriming of CD8 T cells in vivo and protection against tuberculosis...
  35. ncbi request reprint IL-15 regulates CD8+ T cell contraction during primary infection
    Toshiki Yajima
    Division of Host Defense, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Japan
    J Immunol 176:507-15. 2006
    ..These results suggest that IL-15 plays a critical role in protecting effector CD8+ T cells from apoptosis during the contraction phase following a microbial infection via inducing antiapoptotic molecules...