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Articles 1 - 23 of 23
Full-Text Articles in Anatomy
Coculture Of Staphylococcus Aureus With Pseudomonas Aeruginosa Drives S. Aureus Towards Fermentative Metabolism And Reduced Viability In A Cystic Fibrosis Model, Laura M. Filkins, Jyoti A. Graber, Daniel G. Olson, Emily L. Dolben, Lee Lynd, Sabin Bhuju, George A. O'Toole
Coculture Of Staphylococcus Aureus With Pseudomonas Aeruginosa Drives S. Aureus Towards Fermentative Metabolism And Reduced Viability In A Cystic Fibrosis Model, Laura M. Filkins, Jyoti A. Graber, Daniel G. Olson, Emily L. Dolben, Lee Lynd, Sabin Bhuju, George A. O'Toole
Dartmouth Scholarship
The airways of patients with cystic fibrosis are colonized with diverse bacterial communities that change dynamically during pediatric years and early adulthood. Staphylococcus aureus is the most prevalent pathogen during early childhood, but during late teens and early adulthood, a shift in microbial composition occurs leading to Pseudomonas aeruginosa community predominance in ∼50% of adults. We developed a robust dual-bacterial in vitro coculture system of P. aeruginosa and S. aureus on monolayers of human bronchial epithelial cells homozygous for the ΔF508 cystic fibrosis transmembrane conductance regulator (CFTR) mutation to better model the mechanisms of this interaction. We show that P. …
The Role Of Il-27 In Susceptibility To Post-Influenza Staphylococcus Aureus Pneumonia, Keven M. Robinson, Benjamin Lee, Erich V Scheller, Sivanarayana Mandalapu, Richard I. Enelow
The Role Of Il-27 In Susceptibility To Post-Influenza Staphylococcus Aureus Pneumonia, Keven M. Robinson, Benjamin Lee, Erich V Scheller, Sivanarayana Mandalapu, Richard I. Enelow
Dartmouth Scholarship
Influenza is a common respiratory virus and Staphylococcus aureus frequently causes secondary pneumonia during influenza infection, leading to increased morbidity and mortality. Influenza has been found to attenuate subsequent Type 17 immunity, enhancing susceptibility to secondary bacterial infections. IL-27 is known to inhibit Type 17 immunity, suggesting a potential critical role for IL-27 in viral and bacterial co-infection.
Prevalence Of Streptococci And Increased Polymicrobial Diversity Associated With Cystic Fibrosis Patient Stability, L. M. Filkins, T. H. Hampton, A. H. Gifford, M. J. Gross, D. A. Hogan, M. L. Sogin, H. G. Morrison, B. J. Paster, G. A. O'Toole
Prevalence Of Streptococci And Increased Polymicrobial Diversity Associated With Cystic Fibrosis Patient Stability, L. M. Filkins, T. H. Hampton, A. H. Gifford, M. J. Gross, D. A. Hogan, M. L. Sogin, H. G. Morrison, B. J. Paster, G. A. O'Toole
Dartmouth Scholarship
Diverse microbial communities chronically colonize the lungs of cystic fibrosis patients. Pyrosequencing of amplicons for hypervariable regions in the 16S rRNA gene generated taxonomic profiles of bacterial communities for sputum genomic DNA samples from 22 patients during a state of clinical stability (outpatients) and 13 patients during acute exacerbation (inpatients). We employed quantitative PCR (qPCR) to confirm the detection of Pseudomonas aeruginosa and Streptococcus by the pyrosequencing data and human oral microbe identification microarray (HOMIM) analysis to determine the species of the streptococci identified by pyrosequencing. We show that outpatient sputum samples have significantly higher bacterial diversity than inpatients, but …
Functional Genomics Reveals An Essential And Specific Role For Stat1 In Protection Of The Central Nervous System Following Herpes Simplex Virus Corneal Infection, Tracy J. Pasieka, Cristian Cilloniz, Victoria S. Carter, Pamela Rosato, Michael G. Katze, David A. Leib
Functional Genomics Reveals An Essential And Specific Role For Stat1 In Protection Of The Central Nervous System Following Herpes Simplex Virus Corneal Infection, Tracy J. Pasieka, Cristian Cilloniz, Victoria S. Carter, Pamela Rosato, Michael G. Katze, David A. Leib
Dartmouth Scholarship
Innate immune deficiencies result in a spectrum of severe clinical outcomes following infection. In particular, there is a strong association between loss of the signal transducer and activator of transcription (Stat) pathway, breach of the blood-brain barrier (BBB), and virus-induced neuropathology. The gene signatures that characterize resistance, disease, and mortality in the virus-infected nervous system have not been defined. Herpes simplex virus type 1 (HSV-1) is commonly associated with encephalitis in humans, and humans and mice lacking Stat1 display increased susceptibility to HSV central nervous system (CNS) infections. In this study, two HSV-1 strains were used, KOS (wild type [WT]), …
Protection And Attachment Of Vibrio Cholerae Mediated By The Toxin-Coregulated Pilus In The Infant Mouse Model, Shelly J. Krebs, Ronald K. Taylor
Protection And Attachment Of Vibrio Cholerae Mediated By The Toxin-Coregulated Pilus In The Infant Mouse Model, Shelly J. Krebs, Ronald K. Taylor
Dartmouth Scholarship
Colonization of the human small intestine by Vibrio cholerae is an essential step in pathogenesis that requires the type IV toxin-coregulated pilus (TCP). To date, three functions of TCP have been characterized: it serves as the CTXΦ receptor, secretes the colonization factor TcpF, and functions in microcolony formation by mediating bacterium-bacterium interactions. Although type IV pili in other pathogenic bacteria have been characterized as playing a major role in attachment to epithelial cells, there are very few studies to suggest that TCP acts as an attachment factor. Taking this into consideration, we investigated the function of TCP in attachment to …
Interferon Regulatory Factor 3-Dependent Pathways Are Critical For Control Of Herpes Simplex Virus Type 1 Central Nervous System Infection, Vineet D. Menachery, Tracy J. Pasieka, David A. Leib
Interferon Regulatory Factor 3-Dependent Pathways Are Critical For Control Of Herpes Simplex Virus Type 1 Central Nervous System Infection, Vineet D. Menachery, Tracy J. Pasieka, David A. Leib
Dartmouth Scholarship
The initiation of the immune response at the cellular level relies on specific recognition molecules to rapidly signal viral infection via interferon (IFN) regulatory factor 3 (IRF-3)-dependent pathways. The absence of IRF-3 would be expected to render such pathways inoperative and thereby significantly affect viral infection. Unexpectedly, a previous study found no significant change in herpes simplex virus (HSV) pathogenesis in IRF-3−/− mice following intravenous HSV type 1 (HSV-1) challenge (K. Honda, H. Yanai, H. Negishi, M. Asagiri, M. Sato, T. Mizutani, N. Shimada, Y. Ohba, A. Takaoka, N. Yoshida, and T. Taniguchi, Nature 434:772-777, 2005). In contrast, the …
Crystal Structure Of The Cystic Fibrosis Transmembrane Conductance Regulator Inhibitory Factor Cif Reveals Novel Active-Site Features Of An Epoxide Hydrolase Virulence Factor, Christopher D. Bahl, Christophe Morisseau, Jennifer M. Bomberger, Bruce A. Stanton, Bruce D. Hammock, George A. O'Toole, Dean R. Madden
Crystal Structure Of The Cystic Fibrosis Transmembrane Conductance Regulator Inhibitory Factor Cif Reveals Novel Active-Site Features Of An Epoxide Hydrolase Virulence Factor, Christopher D. Bahl, Christophe Morisseau, Jennifer M. Bomberger, Bruce A. Stanton, Bruce D. Hammock, George A. O'Toole, Dean R. Madden
Dartmouth Scholarship
Cystic fibrosis transmembrane conductance regulator (CFTR) inhibitory factor (Cif) is a virulence factor secreted by Pseudomonas aeruginosa that reduces the quantity of CFTR in the apical membrane of human airway epithelial cells. Initial sequence analysis suggested that Cif is an epoxide hydrolase (EH), but its sequence violates two strictly conserved EH motifs and also is compatible with other alpha/beta hydrolase family members with diverse substrate specificities. To investigate the mechanistic basis of Cif activity, we have determined its structure at 1.8-A resolution by X-ray crystallography. The catalytic triad consists of residues Asp129, His297, and Glu153, which are conserved across the …
Gbdr Regulates Pseudomonas Aeruginosa Plch And Pchp Transcription In Response To Choline Catabolites, Matthew J. Wargo, Tiffany C. Ho, Maegan J. Gross, Laurie A. Whittaker, Deborah A. Hogan
Gbdr Regulates Pseudomonas Aeruginosa Plch And Pchp Transcription In Response To Choline Catabolites, Matthew J. Wargo, Tiffany C. Ho, Maegan J. Gross, Laurie A. Whittaker, Deborah A. Hogan
Dartmouth Scholarship
Pseudomonas aeruginosa hemolytic phospholipase C, PlcH, can degrade phosphatidylcholine (PC) and sphingomyelin in eukaryotic cell membranes and extracellular PC in lung surfactant. Numerous studies implicate PlcH in P. aeruginosa virulence. The phosphorylcholine released by PlcH activity on phospholipids is hydrolyzed by a periplasmic phosphorylcholine phosphatase, PchP. Both plcH gene expression and PchP enzyme activity are positively regulated by phosphorylcholine degradation products, including glycine betaine. Here we report that the induction of plcH and pchP transcription by glycine betaine is mediated by GbdR, an AraC family transcription factor. Mutants that lack gbdR are unable to induce plcH and pchP in media …
Smoking Enhances Risk For New External Genital Warts In Men, Dorothy J. Wiley, David Elashoff, Emmanuel V. Masongsong, Diane M. Harper
Smoking Enhances Risk For New External Genital Warts In Men, Dorothy J. Wiley, David Elashoff, Emmanuel V. Masongsong, Diane M. Harper
Dartmouth Scholarship
Repeat episodes of HPV-related external genital warts reflect recurring or new infections. No study before has been sufficiently powered to delineate how tobacco use, prior history of EGWs and HIV infection affect the risk for new EGWs. Behavioral, laboratory and examination data for 2,835 Multicenter AIDS Cohort Study participants examined at 21,519 semi-annual visits were evaluated. Fourteen percent (391/2835) of men reported or were diagnosed with EGWs at 3% (675/21,519) of study visits. Multivariate analyses showed smoking, prior episodes of EGWs, HIV infection and CD4+ T-lymphocyte count among the infected, each differentially influenced the risk for new EGWs.
Detection Of Viruses In Human Adenoid Tissues By Use Of Multiplex Pcr, Masatoki Sato, Haijing Li, Mine R. Ikizler, Jay A. Werkhaven, John V. Williams, James D. Chappell, Yi-Wei Tang, Peter F. Wright
Detection Of Viruses In Human Adenoid Tissues By Use Of Multiplex Pcr, Masatoki Sato, Haijing Li, Mine R. Ikizler, Jay A. Werkhaven, John V. Williams, James D. Chappell, Yi-Wei Tang, Peter F. Wright
Dartmouth Scholarship
By PCR, we detected a high frequency of viruses in adenoids obtained from children without acute respiratory symptoms. Our results suggest that persistent/latent viral infection in the respiratory tract confounds interpretation of the association of pathogen detection by PCR with acute respiratory infection in these sources.
In Vitro Analysis Of Tobramycin-Treated Pseudomonas Aeruginosa Biofilms On Cystic Fibrosis-Derived Airway Epithelial Cells, Gregory G. Anderson, Sophie Moreau-Marquis, Bruce A. Stanton, George A. O'Toole
In Vitro Analysis Of Tobramycin-Treated Pseudomonas Aeruginosa Biofilms On Cystic Fibrosis-Derived Airway Epithelial Cells, Gregory G. Anderson, Sophie Moreau-Marquis, Bruce A. Stanton, George A. O'Toole
Dartmouth Scholarship
P. aeruginosa forms biofilms in the lungs of individuals with cystic fibrosis (CF); however, there have been no effective model systems for studying biofilm formation in the CF lung. We have developed a tissue culture system for growth of P. aeruginosa biofilms on CF-derived human airway cells that promotes the formation of highly antibiotic-resistant microcolonies, which produce an extracellular polysaccharide matrix and require the known abiotic biofilm formation genes flgK and pilB. Treatment of P. aeruginosa biofilms with tobramycin reduced the virulence of the biofilms both by reducing bacterial numbers and by altering virulence gene expression. We performed microarray analysis …
The Flagellum Of Pseudomonas Aeruginosa Is Required For Resistance To Clearance By Surfactant Protein A, Shiping Zhang, Francis X. Mccormack, Roger C. Levesque, George A. O'Toole, Gee W. Lau
The Flagellum Of Pseudomonas Aeruginosa Is Required For Resistance To Clearance By Surfactant Protein A, Shiping Zhang, Francis X. Mccormack, Roger C. Levesque, George A. O'Toole, Gee W. Lau
Dartmouth Scholarship
Surfactant protein A (SP-A) is an important lung innate immune protein that kills microbial pathogens by opsonization and membrane permeabilization. We investigated the basis of SP-A-mediated pulmonary clearance of Pseudomonas aeruginosa using genetically-engineered SP-A mice and a library of signature-tagged P. aeruginosa mutants. A mutant with an insertion into flgE, the gene that encodes flagellar hook protein, was preferentially cleared by the SP-A(+/+) mice, but survived in the SP-A(-/-) mice. Opsonization by SP-A did not play a role in flgE clearance. However, exposure to SP-A directly permeabilized and killed the flgE mutant, but not the wild-type parental strain. P. aeruginosa …
Staphylococcus Aureus Escapes More Efficiently From The Phagosome Of A Cystic Fibrosis Bronchial Epithelial Cell Line Than From Its Normal Counterpart, Todd M. Jarry, Ambrose L. Cheung
Staphylococcus Aureus Escapes More Efficiently From The Phagosome Of A Cystic Fibrosis Bronchial Epithelial Cell Line Than From Its Normal Counterpart, Todd M. Jarry, Ambrose L. Cheung
Dartmouth Scholarship
Staphylococcus aureus is frequently the initial bacterium isolated from young cystic fibrosis (CF) patients, and yet its role in CF disease progression has not been determined. Recent data from our lab demonstrates that S. aureus can invade and replicate within the CF tracheal epithelial cell line (CFT-1). Here we describe the finding that the fate of internalized S. aureus in CFT-1 cells differs from its complemented counterpart (LCFSN). S. aureus strain RN6390 was able to replicate within the mutant CFT-1 cells after invasion but not in the complemented LCFSN cells. At 1 h postinvasion, S. aureus containing vesicles within both …
Do Cd1-Restricted T Cells Contribute To Antibody-Mediated Immunity Against Mycobacterium Tuberculosis?, Mark L. Lang, Aharona Glatman-Freedman
Do Cd1-Restricted T Cells Contribute To Antibody-Mediated Immunity Against Mycobacterium Tuberculosis?, Mark L. Lang, Aharona Glatman-Freedman
Dartmouth Scholarship
No abstract provided.
Tcpf Is A Soluble Colonization Factor And Protective Antigen Secreted By El Tor And Classical O1 And O139 Vibrio Cholerae Serogroups, Thomas J. Kirn, Ronald K. Taylor
Tcpf Is A Soluble Colonization Factor And Protective Antigen Secreted By El Tor And Classical O1 And O139 Vibrio Cholerae Serogroups, Thomas J. Kirn, Ronald K. Taylor
Dartmouth Scholarship
Vibrio cholerae causes diarrhea by colonizing the human small bowel and intoxicating epithelial cells. Colonization is a required step in pathogenesis, and strains defective for colonization are significantly attenuated. The best-characterized V. cholerae colonization factor is the toxin-coregulated pilus (TCP). It has been demonstrated that TCP is required for V. cholerae colonization in both humans and mice. TCP enhances bacterial interactions that allow microcolony formation and thereby promotes survival in the intestine. We have recently discovered that the TCP biogenesis apparatus also serves as a secretion system, mediating the terminal step in the extracellular secretion pathway of TcpF. TcpF was …
Effects Of Estradiol On Lipopolysaccharide And Pam3cys Stimulation Of Ccl20/Macrophage Inflammatory Protein 3 Alpha And Tumor Necrosis Factor Alpha Production By Uterine Epithelial Cells In Culture, Mardi A. Crane-Godreau, Charles R. Wira
Effects Of Estradiol On Lipopolysaccharide And Pam3cys Stimulation Of Ccl20/Macrophage Inflammatory Protein 3 Alpha And Tumor Necrosis Factor Alpha Production By Uterine Epithelial Cells In Culture, Mardi A. Crane-Godreau, Charles R. Wira
Dartmouth Scholarship
We have previously demonstrated that rat uterine epithelial cells (UEC) produce CCL20/macrophage inflammatory protein 3 alpha (MIP3alpha) and tumor necrosis factor alpha (TNF-alpha) in response to live and heat-killed Escherichia coli and to the pathogen-associated molecular patterns (PAMP) lipopolysaccharide (LPS) and Pam3Cys. To determine whether estradiol (E2) modulates PAMP-induced CCL20/MIP3alpha and TNF-alpha secretion, primary cultures of rat UEC were incubated with E2 for 24 h and then treated with LPS or Pam3Cys or not treated for an additional 12 h. E2 inhibited the constitutive secretion of TNF-alpha and CCL20/MIP3alpha into culture media. Interestingly, E2 pretreatment enhanced CCL20/MIP3alpha secretion due to …
Staphylococcus Aureus Agr And Sara Functions Are Required For Invasive Infection But Not Inflammatory Responses In The Lung, Geoffrey Heyer, Shahryar Saba, Robert Adamo, William Rush, Grace Soong, Ambrose Cheung, Alice Prince
Staphylococcus Aureus Agr And Sara Functions Are Required For Invasive Infection But Not Inflammatory Responses In The Lung, Geoffrey Heyer, Shahryar Saba, Robert Adamo, William Rush, Grace Soong, Ambrose Cheung, Alice Prince
Dartmouth Scholarship
Staphylococcus aureus strains lacking agr- and sarA-dependent gene products or specific MSCRAMM (microbial surface components recognizing adhesive matrix molecules) adhesins were compared for the ability to activate inflammatory responses in the lung. The mutants were evaluated for virulence in a mouse model of pneumonia and by quantifying their ability to stimulate interleukin-8 (IL-8) and granulocyte-macrophage colony-stimulating factor (GM-CSF) expression in respiratory epithelial cells. In a neonatal mouse, only strains with intact agr and sarA loci were consistently associated with invasive, fatal pulmonary infection (P < 0.001) and sarA was specifically required to cause bacteremia (P < 0.001). The agr and/or sarA mutants were, nonetheless, fully capable of producing pneumonia and were as proficient as the wild-type strain in stimulating epithelial IL-8 expression, a polymorphonuclear leukocyte chemokine, in airway cells. In contrast, agr and especially sarA mutants induced less epithelial GM-CSF expression, and MSCRAMM mutants lacking fibronectin binding proteins or clumping factor A, a ligand for fibrinogen, were unable to stimulate epithelial GM-CSF production. The ability to induce IL-8 expression was independent of the adherence properties of intact bacteria, indicating that shed and/or secreted bacterial components activate epithelial responses. While conserved staphylococcal components such as peptidoglycan are sufficient to evoke inflammation and cause pneumonia, the agr and sarA loci of S. aureus are critical for the coordination of invasive infection of the lungs.
Anti-Class Ii Monoclonal Antibody-Targeted Vibrio Cholerae Tcpa Pilin: Modulation Of Serologic Response, Epitope Specificity, And Isotype, Jia-Yan Wu, Ronald K. Taylor, William F. Wade
Anti-Class Ii Monoclonal Antibody-Targeted Vibrio Cholerae Tcpa Pilin: Modulation Of Serologic Response, Epitope Specificity, And Isotype, Jia-Yan Wu, Ronald K. Taylor, William F. Wade
Dartmouth Scholarship
Toxin-coregulated pilus (TCP) is a colonization factor required for cholera infection. It is not a strong immunogen when delivered in the context of whole cells, yet pilus subunits or TcpA derivative synthetic peptides induce protective responses. We examined the efficacy of immunizing mice with TCP conjugated to anti-class II monoclonal antibodies (MAb) with or without the addition of cholera toxin (CT) or anti-CD40 MAb to determine if the serologic response to TcpA could be manipulated. Anti-class II MAb-targeted TCP influenced the anti-TCP peptide serologic response with respect to titer and isotype. Responses to TcpA peptide 4 were induced with class …
Staphylococcus Aureus Rn6390 Replicates And Induces Apoptosis In A Pulmonary Epithelial Cell Line, Barbara C. Kahl, Mark Goulian, Willem Van Wamel, Mathias Herrmann, Sanford M. Simon, Gilla Kaplan, Georg Peters, Ambrose L. Cheung
Staphylococcus Aureus Rn6390 Replicates And Induces Apoptosis In A Pulmonary Epithelial Cell Line, Barbara C. Kahl, Mark Goulian, Willem Van Wamel, Mathias Herrmann, Sanford M. Simon, Gilla Kaplan, Georg Peters, Ambrose L. Cheung
Dartmouth Scholarship
Staphylococcus aureus frequently colonizes the airways of patients with compromised airway defenses (e.g., cystic fibrosis [CF] patients) for extended periods. Persistent and relapsing infections may be related to live S. aureus bacteria actively residing inside epithelial cells. In this study, we infected a respiratory epithelial cell line, which was derived from a CF patient, with S. aureus RN6390. Internalization of S. aureus was found to be time and dose dependent and could be blocked by cytochalasin D. Transmission electron microscopy revealed that internalized bacteria resided within endocytic vacuoles without any evidence of lysosomal fusion in a 24-h period. The results …
Effects Of Estradiol And Progesterone On Susceptibility And Early Immune Responses To Chlamydia Trachomatis Infection In The Female Reproductive Tract, Charu Kaushic, Fan Zhou, Andrew D. Murdin, Charles R. Wira
Effects Of Estradiol And Progesterone On Susceptibility And Early Immune Responses To Chlamydia Trachomatis Infection In The Female Reproductive Tract, Charu Kaushic, Fan Zhou, Andrew D. Murdin, Charles R. Wira
Dartmouth Scholarship
We have used a previously described rodent model to examine the influence of hormonal environment on susceptibility and immune responses to genital Chlamydia infection. Ovariectomized rats were administered estradiol, progesterone, or a combination of both, infected with Chlamydia trachomatis via the intrauterine route, and sacrificed 5 days later. Histopathological examination showed severe inflammation in the uteri and vaginae of progesterone-treated animals, whereas animals receiving estradiol or a combination of both hormones showed no inflammation. Large numbers of chlamydiae were found in vaginal secretions of progesterone-treated and combination-treated animals, while estradiol-treated animals had none. Tissue localization showed that numerous chlamydial inclusions …
Chlamydia Trachomatis Infection In The Female Reproductive Tract Of The Rat: Influence Of Progesterone On Infectivity And Immune Response, Charu Kaushic, Andrew D. Murdin, Brian J. Underdown, Charles R. Wira
Chlamydia Trachomatis Infection In The Female Reproductive Tract Of The Rat: Influence Of Progesterone On Infectivity And Immune Response, Charu Kaushic, Andrew D. Murdin, Brian J. Underdown, Charles R. Wira
Dartmouth Scholarship
As the most common cause of sexually transmitted disease in women, chlamydial infections can lead to pelvic inflammatory disease, infertility, and ectopic pregnancy. To better understand the role played by sex hormones in modulating the immune response of the genital tract to microbial infections, we have developed a rat model to study Chlamydia trachomatis infection. Inbred female Lewis rats were primed with progesterone and inoculated by intrauterine instillation of C. trachomatis (mouse pneumonitis strain MoPn) into each uterine horn. When infected animals were examined for the presence of chlamydial antigens 14 days postinfection, both the uterus and vagina were found …
Toxin-Coregulated Pilus, But Not Mannose-Sensitive Hemagglutinin, Is Required For Colonization By Vibrio Cholerae O1 El Tor Biotype And O139 Strains., K Helene Thelin, Ronald K. Taylor
Toxin-Coregulated Pilus, But Not Mannose-Sensitive Hemagglutinin, Is Required For Colonization By Vibrio Cholerae O1 El Tor Biotype And O139 Strains., K Helene Thelin, Ronald K. Taylor
Dartmouth Scholarship
The relative contributions of toxin-coregulated pilus (TCP) and cell-associated mannose-sensitive hemagglutinin (MSHA) to the colonization ability of Vibrio cholerae O1 El Tor biotype strains and O139 Bengal strains was determined by using isogenic parental and in-frame deletion mutant pairs in the infant mouse cholera model. Both the El Tor and O139 tcpA mutant strains showed a dramatic defect in colonization as indicated by their competitive indices, whereas deletion of mshA had a negligible effect on colonization in either background.
Impairment Of The Cellular Immune Response In Acute Murine Toxoplasmosis: Regulation Of Interleukin 2 Production And Macrophage-Mediated Inhibitory Effects., Sakhina Haque, Imtiaz Khan, Azizul Haque, Lloyd Kasper
Impairment Of The Cellular Immune Response In Acute Murine Toxoplasmosis: Regulation Of Interleukin 2 Production And Macrophage-Mediated Inhibitory Effects., Sakhina Haque, Imtiaz Khan, Azizul Haque, Lloyd Kasper
Dartmouth Scholarship
Depression of the cellular immune response to Toxoplasma gondii has been reported in both mice and humans. The present study was undertaken to determine the kinetics and mechanism of the observed downregulation of interleukin 2 (IL-2) production during experimental murine toxoplasmosis. For these investigations, the cell-mediated immune response to the wild type (PTg) was compared with that to the less-virulent mutant parasite (PTgB), which is deficient in the major surface antigen, p30 (SAG-1). Spleen cells from infected A/J mice failed to proliferate in response to Toxoplasma antigens during the first week of infection. Both PTg- and PTgB-infected A/J mice exhibited …