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Laboratory of Immunobiochemistry. Research update. Active research projects. PI Rabin MDR proteins in T cell activation Regulation of T cell responses by the Respiratory Syncytial Virus PI Slater Cockroach allergen standardization Determination of optimal surrogate test
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Laboratory of Immunobiochemistry Research update
Active research projects • PI Rabin • MDR proteins in T cell activation • Regulation of T cell responses by the Respiratory Syncytial Virus • PI Slater • Cockroach allergen standardization • Determination of optimal surrogate test • Depletion analysis of CR extracts • Endotoxin in allergen vaccines
Publications Research • Spann KM, Tran KC, Chi B, Rabin RL, Collins PL. Suppression of the induction of alpha, beta, and lambda interferons by the NS1 and NS2 proteins of human respiratory syncytial virus in human epithelial cells and macrophages. J Virol 2004; 78(8):4363-9. • Song K, Rabin RL, Douek D, Roederer M, Farber JM. Novel Subsets of CD4+ Memory T Cells Reveal Early Branched Pathways of T Cell Differentiation in Humans. Proc Natl Acad Sci, in press • Zhang J, Alston MA, Huang H, Rabin RL. Multidrug Resistant Protein 1 (MRP1) is induced upon activation of human T cells, and its inhibition blocks T cell function, in preparation
Publications Review • Slater JE. Recombinant allergens in the US. Methods 2004; 32(3):209-11. • Slater JE. Latex allergens. Clin Allergy Immunol 2004;18:369-86. • Slater JE. Standardized allergen extracts in the United States. Clin Allergy Immunol 2004;18:421-32. • Rabin RL. Respiratory Syncytial Virus exploits genetic and environmental risk factors for asthma; Business Briefing, US Pediatric Care 2005, in press • Rabin RL, Levinson AI, Apter AJ. Coincidence of autoimmune and allergic diseases: epidemiologic and mechanistic analyses, in preparation
Abstracts B Chi, M Alston, KM Spann, PL Collins, RL Rabin. A critical role for dendritic cells in immunosuppression caused by the respiratory syncytial virus (RSV). J Allergy Clin Immunol 2005; 115:S226 NC deVore, WJJ Finlay, EN Dobrovolskaia, A Gam, JE Slater. Cloning and analysis of mono-specific single chain fragment variable scFv fragments that recognize German cockroach allergens Bla g 1, Bla g 2, Bla g 4, and Bla g 5. J Allergy Clin Immunol 2005; 115:S163 E Dobrovolskaia, A Gam, JE Slater. Competition ELISA can be a sensitive method for the specific detection of small quantities of allergen in a complex mixture. J Allergy Clin Immunol 2005; 115:S164 J Zhang, MA Alston, H Huang, RA Houghtling, RW Pastor, RL Rabin. Human type 1 CD4 T cell cytokine responses are selectively dependent on Multidrug Resistance Protein1. J Allergy Clin Immunol 2005; 115:S255 C Valerio, LG Arlian, JE Slater. Bacterial 16S ribosomal DNA sequences isolated from house dust mites. J Allergy Clin Immunol 2005; 115:S163
Invited presentations - Rabin • AAAAI Annual Meeting, March 2004: • FDA Food and Cosmetics Act as it Applies to Research Studies • Paul-Ehrlich-Seminar, October 2005: • Recombinant and modified allergens: The US perspective
Invited presentations - Slater • American Contact Dermatitis Society, October 2004 meeting: • Natural rubber latex allergy • ACAAI Annual Meeting, November 2004, Immunotherapy Collegium: • Allergen immunotherapy in the era of uncertainty • AAAAI Annual Meeting, March 2005: • Allergen identification
Larry G. Arlian, PhD Director, Microbiology and Immunology, Department of Biological Sciences, Wright State University, Dayton, Ohio Patrick R. Murray, PhD Chief, Microbiology Service, NIH Clinical Center, Bethesda, Maryland Immunotherapy Committee, AAAAI Harold Nelson, MD Peter L. Collins, PhD Laboratory of Infectious Diseases, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, Maryland Mario Roederer, PhD Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, Maryland Outside collaborations
Allergy and asthma are T cell dependent • T cells are allergen responsive and secrete cytokines involved in the allergic response (IL-4, IL-5, and IL-13) • Allergen immunotherapy works by modifying T cell responses • Novel approaches towards modifying T cell responses may provide novel therapeutics for treatment of allergic diseases and asthma • The link between respiratory viral infections and wheezing is mediated by T cells • Understanding T cell responses to respiratory viruses will provide insight into the mechanisms of allergy and asthma
Allergy and asthma are T cell dependent • T cells are allergen responsive and secrete cytokines involved in the allergic response (IL-4, IL-5, and IL-13) • Allergen immunotherapy works by modifying T cell responses • Novel approaches towards modifying T cell responses may provide novel therapeutics for treatment of allergic diseases and asthma • The link between respiratory viral infections and wheezing is mediated by T cells • Understanding T cell responses to respiratory viruses will provide insight into the mechanisms of allergy and asthma
MK-571, an inhibitor of Multidrug Resistant Protein 1 (MRP1) blocks T cell activation
Activation affects [probe] [probe] reflects gene expression of probe transporter Does probe transporter modulate activation? observation
MDR Family • Proteins that transport substances across cellular membranes, against a concentration gradient, in an energy dependent manner. • ABC proteins (ATP Binding Cassette) that contain distinctive nucleotide binding domains (NBD). • Genes are highly conserved across species. • First member is MDR1 (P-glycoprotein, P-gp); best substrates are large hydrophobic cations. • MDR-associated Resistant Protein-1 (MRP1) described in 1992; substrates are organic anions, and also: • glutathione, glucuronide, & sulfate conjugates • LTC4
MDR1 MRP1 MRP3 MDR family gene expression in T cells35 cycle RT-PCR specific products CD4 CD8 Cord CD4 naive memory naive memory B cells NK cells 3 days 0 day Monocytes ACTIN
MK-571 blocks morphologic changes associated with PBMC activation TSST-1 10 ng/ ml Control MK-571 (100µM) 40x
MK-571 decreases expression of CD69 in response to superantigens
The MRP1 inhibitor MK-571 decreases IFN-g and IL-4 by superantigen stimulated CD4 T cells
PHA+PGJ2 PHA+MK PHA+CE Blank Med PHA Lane 1 2 3 4 5 6 Increased PPARg activation in Jurkat T cells treated with MK-571 Jurkat T cells treated with PHA for 24 hours, and then PPARg agonists or MK-571 for 1 hour prior to harvest. MK: MK-571 50uM CE: Ciglitazone 20uM PGJ2: Prostaglandin J2 10uM
Conclusions • Inhibition of MRP1 with MK-571 blocks T cell activation • MK-571 does not decrease the viability of the activated cells (not shown) • “Washout” of MK-571 reverses the inhibition of activation (not shown) • Treatment of cells with MK-571 activates the transcriptional repressor PPARg • Hypothesis: endogenous ligands for PPARg are retained in MRP1 blocked cells
Allergy and asthma are T cell dependent • T cells are allergen responsive and secrete cytokines involved in the allergic response (IL-4, IL-5, and IL-13) • Allergen immunotherapy works by modifying T cell responses • Novel approaches towards modifying T cell responses may provide novel therapeutics for treatment of allergic diseases and asthma • The link between respiratory viral infections and wheezing is mediated by T cells • Understanding T cell responses to respiratory viruses will provide insight into the mechanisms of allergy and asthma
Regulation of T cell responses by the Respiratory Syncytial Virus
RSV inhibition of T cell proliferation • RSV depresses proliferation of PBMC to PHA, EBV, or to RSV antigens in vitro (Roberts, 1982; Preston et al, 1992). • RSV stimulates inhibitors of proliferation such as prostaglandins (Panuska et al, 1990), “IL-1 inhibitors” (Roberts et al, 1986 and interferon-a (Preston et al, 1995). • Direct contact with RSV F (fusion protein) is necessary and sufficient to inhibit proliferation of lymphocytes (Schlender et al, 2002).
Experimental approach • Published data have implicated various cytokines and inhibitors, or contact dependency, most unconfirmed or refuted • Goal: Develop a simplified model to determine which cells are necessary and/or sufficient for inhibition of proliferation by RSV.
DC + RSV L 4 hr + SEB 4 days H3 thymidine uptake assay Inhibition of SEB-induced T cell proliferation by RSV DC = monocyte-derived dendritic cells SEB = staphylococcal enterotoxin B
RSV significantly inhibits CMV specific and SEB-activated T cell proliferation
DC + DC + Virus Virus L CD4 4 hr 4 hr + SEB 4 days + SEB 4 days H3 thymidine uptake assay H3 thymidine uptake assay Do CD8 T cells, NK cells, or B cells mediate immunosuppression?
CD4 T cells and DC are sufficient for suppression of proliferation by RSV P>0.05 P< 0.05 P=0.003 P<0.05 SEB SEB SEB SEB RSV FLU paraflu SEB SEB SEB SEB RSV FLU paraflu
DC + RSV ON Supernatant Add to CD4 4 days + SEB H3 thymidine uptake assay Can suppressive activity be transferred with DC supernatants?
Inhibition of CD4+ T cell proliferation by DC supernatant P = 0.001 P>0.05 DC sup: UV RSV control RSV
Conclusions • We have simplified the experimental system of RSV-mediated immunosuppression to monocyte-derived DC and CD4 T cells • Immunosuppressive activity can be transferred with supernatants from infected DC, and is not due to carry over of virus within the supernatants
Laboratory of Immunobiochemistry CBER, FDA Marc Alston Jinsong Zhang Hui Huang Bo Chi Jay Slater Laboratory of Infectious Diseases NIAID, NIH Peter L. Collins Immunotechnology Section VRC, NIH Laboratory of Biophysics CBER, FDA Steve Perfetto Mario Roederer Rich Pastor Acknowledgments