S67Abstracts

The HIV broadly neutralizing antibody 2F5 binds to gp41at the membrane proximal region (MPER). The primaryCDR-H3 repertoire is typically depleted of hydrophobicamino acids, but enriched for tyrosine. The 2F5 CDR-H3contains no tyrosine. Instead, it uses hydrophobic aminoacids to interact with gp41 and the virus membrane. To testwhether the frequency of binding to the MPER region couldbe influenced by changing the composition of the primaryimmunoglobulin repertoire, we challenged D-limited ΔD-DμFS mice with JRFL gp140. ΔD-DμFS mice express aprimary CDR-H3 repertoire enriched for hydrophobic aminoacids. Although the endpoint titer against JRFL gp140 as awhole was identical between ΔD-DμFS and wild-type mice,the endpoint titer against an MPER region peptide andagainst a consensus subtype B V3 loop peptide in the ΔD-DμFS mice was two and three times that of wild-type,respectively. In contrast, the end point titer against apeptide derived from the immunodominant region of gp41was four-fold reduced. These findings suggest that epitopeselection against HIV is greatly influenced by the composi-tion of the primary repertoire. This work supported by NIHAI48115-S1 and AI078449.

doi:10.1016/j.clim.2009.03.194

T.60. Defect of Plasmacytoid Dendritic Cells inWHIM PatientsLaura Tassone, Daniele Moratto, Lucia Notarangelo,Fulvio Porta, Vassilios Lougaris, Alessandro Plebani, RaffaeleBadolato. Istituto di Medicina Molecolare “Angelo Nocivelli”and Clinica Pediatrica, Brescia, Italy

WHIM syndrome is a primary immunodeficiency charac-terized by the association of severe/moderate neutropeniadespite retention of mature neutrophils in bone marrow (e.g.myelokathexis), hypogammaglobulinemia, recurrent infec-tions and severe skin warts, which is caused by heterozygousmutations in the C-tail of chemokine receptor CXCR4. Thisdisease is characterized by abnormal trafficking of leuko-cytes between bloodstream, lymphoid organs and skincompartment, due to an increased chemotactic response toCXCL12 (previously reported by our group in T lymphocytesand PMN). Plasmacytoid dendritic cells (pDC) have beenreported to be recruited to the site of inflammation and tothe lymph node by chemokines, expressed by endothelialcells surrounding the tissues where the infection is located.Because WHIM syndrome is often associated to cutaneousverrucae vulgaris infections (caused by common HPVgenotypes), we are investigating the ability of dendriticcells (DC) to mount an immune response against viruses andopportunistic pathogens. In order to assess the effect ofCXCR4 truncating mutations on the homeostasis of pDC inWHIM patients, we have performed a quantitative evaluationof DC subpopulations (myeloid DC (CD4+CD1c+BDCA-2-) andplasmacytoid DC (CD4+CD1c-BDCA-2+)) by FACS analysis, inperipheral blood of 4 WHIM patients bearing mutationsR334×and G336X. In WHIM patients we have observed asignificant reduction in the percentage of both subsets of DC,compared to healthy subjects; in particular, we have found asignificant decrease in the percentage of pDC subset,

suggesting an altered homeostasis and a defect in DC traf-ficking between blood and tissues.

doi:10.1016/j.clim.2009.03.195

T.61. Mortality is Associated with Rates ofPeripheral Blood NK, B and Treg Cells in Patientswith Non-Small Cell Lung CancerBayram Kiran2, Akif Turna1, Akif Ozgul1, Atilla Gurses1,Selim Badur2. 1Yedikule Teaching Hospital for Chest Diseasesand Thoracic Surgery, Istanbul, Turkey; 2Department ofMicrobiology and Immunology, Istanbul, Turkey

Introduction: Lung cancer has been leading cause incancer-related deaths. Chemotherapy drastically affect per-formance status and immune system in non-small cell lungcancer patients. We aimed to analyze the relationship bet-ween clinicopathologic parameters and peripheral bloodlymphocyte subgroups. Patients and Methods: BetweenOctober 2007 and May 2008, 20 patients (19 males, 1 female)who had inoperable non-small cell lung cancer receivingcisplatin-based chemotherapy were enrolled in the study.The mean age was 61 years. The ratios of white blood cells,peripheral blood mononuclear cells and subpopulations wereanalyzed using flow cytometry. There was no statisticallysignificant difference between pre and post-chemotherapyratios of subpopulations. However, mortality was found to beassociated with NK cells (p b0.001), B lymphocytes(p=0.001), CD8+CD28-cells (pb0.001), NKT cells (pb0.001)and Treg cells (p=0.024). No relationship between otherparameters and mortality was found. Discussion: Chemo-therapy caused a substantial morbidity and a mortality.However, unforeseen deaths occur during therapy. Certaincell populations could be related to antii-tumor immunity andmortality in these patients. As a conclusion, ratios of NK cells,NKT cells, B lymphocytes and Treg cells seemed to beassociated with unpredicted mortality in non-small cell lungcancer patients.

doi:10.1016/j.clim.2009.03.196

FOCIS Pillar: Immunotherapy

T.62. Smegmosomes: Immune Response andProphylactic Efficacy in Hamster Model ofLeptospirosisSyed Faisal, Wei Wei Yan, Sean McDonough, Yung-Fu Chang.Cornell University, Ithaca, NY

Leptospirosis is an important zoonotic disease thatafflicts both animals and humans. Subunit vaccine isattractive intervention strategy against the disease butneeds potent, yet nontoxic adjuvants for effective imple-mentation. Among the candidates for adjuvants, liposomeshave garnered recent attention for their capacity as carriersof vaccines. In present study we prepared novel liposomes

S68 Abstracts

from total polar lipids of non pathogenic M. Smegmatis(designated Smegmosomes), evaluated its vaccine delivery/adjuvant potential with novel protective antigens ofleptospira (Lp0607, Lp1118, Lp1454) and compared tothose induced by conventional liposomes and aluminumhydroxide adjuvant(alum) in hamster model of leptospirosis.Our results demonstrate that smegmosomes carrying anti-gens have proved to be better adjuvant than conventionalliposomes and alum as revealed by enhanced and long termantibody response, lymphocyte proliferation and significantenhancement in both Th1 (IFN-γ) and Th2 (IL-4, IL-10)cytokines. Additionally, smegmosomes induced memoryresponse which was significantly higher than conventionalliposomes. Above all it imparted significantly higher level ofprotection than those achieved with conventional liposomesand alum as revealed by enhanced survival, reducedhistopathological lesions and bacterial load in vital organs.Taken together, the data of the present study suggests thatsmegmosomes have emerged as promising delivery vehicle/adjuvant that can induce both Th1 and Th2 type immuneresponse and would surely find scope in development ofimproved vaccines for leptospira and other infectiousdiseases.

doi:10.1016/j.clim.2009.03.197

T.63. Chronic Monoarticular Arthritis andEczematous Skin Rash as Initial Manifestations ofPrimary AgammaglobulinemiaSara Kashef, Tooba Momen, Behzad Heidari. ShirazUniversity of Medical Sciences, Shiraz, Iran

Primary immune deficiencies have been reported to beassociated with arthritis, mainly in humoral immune de-ficiencies. Here we report a case of primary agamma-globulinemia initially manifested by chronic arthritis ofleft knee joint and eczematous skin rash. The case was an8 year old boy presented initially with monoarticular arthritisof left knee and eczematous skin rash on extremities for thelast 3 years. There was not evidence of septic arthritis, andhad not responded to treatment for juvenile chronicarthritis. He developed chronic cough, repeated respira-tory infections and failure to thrive for the last 2 years.Quantitative immunoglobulin evaluation showed hypo-gammaglobulinemia with IgGb1.9 g/l, IgAb0.16 g/l, IgM0.26 g/l, and IgE 5.2 Iu/ml. He had deficient antibodyresponse to hepatitis and tetanus vaccines. Flow cytome-tric analysis of peripheral blood mononuclear cells re-vealed no presence of CD19+cells, 88% CD3+,26% CD4+,79%CD8+cells, and inversion of CD4+/CD8+(.33) . The case wasdiagnosed as primary agammaglobulinemia. Regular intra-venous gammaglobulin administration resultes in dramaticimprovement in the respiratory symptoms and growth butstill joint movement is limited after three months of follow-up. The findings indicate that primary agammaglobulinemiamight be manifested as chronic aseptic arthritis and earlyrecognition is important for prevention of complications.

doi:10.1016/j.clim.2009.03.198

T.64. Chemokine Signatures in Pathogenesis andPrevention of Type 1 DiabetesJens Eberlein, Linda N. Stiles, Francisco Victorino, TomNguyen, Dirk Homann. University of Colorado Denver,Barbara Davis Center for Childhood Diabetes, Aurora CO

Type 1 diabetes (T1D) is an autoimmune disease of multi-factorial etiology. While the contribution of genetic suscept-ibilities and environmental factors to T1D pathogenesisremain to be elucidated in detail, T cells specific for beta-cell-derived antigens appear to be the cardinal effectors inboth mouse and man. Despite progress in the past years, theprecise temporo-spatial coordination of T cell responsesinvolved in initiation and perpetuation of destructiveautoimmunity remains incompletely understood. Recentwork on T1D pathogenesis has emphasized the potentialimportance of chemokines, a large family of mainly secretedmolecules involved in numerous physiological and patho-physiological processes. Indeed, as many as half of allchemokines have been associated with T1D development,yet an integration of these observations into a coherentperspective on T1D pathogenesis has been difficult. Thesechallenges pertain in particular to the precise characteriza-tion of chemokine-producing cells and the full spectrum ofchemokines expressed by defined cellular subsets. Using acombination of gene arrays, novel flow cytometric andimmunofluorescence assays we have begun to define thecomplete spectrum of chemokine proteins expressed by isletcells, diabetogenic T cells and other islet infiltrating cells inmurine models of virus-induced and spontaneous T1D. Basedon these results, we have initiated in vivo studies to asses thepathogenic contribution individual chemokines. Our resultsare expected to provide a rational foundation for the dev-elopment of therapeutic strategies that will explore theutility and limitations of targeting the chemokine system atlarge for the purpose of prevention and possibly reversion ofT1D.

doi:10.1016/j.clim.2009.03.199

T.65. Immunotherapy with Anti-CD40 and IL-2Results in Antigen Independent CD8+T CellProliferation in vivo and AugmentedNKG2D-Mediated Tumor Lysis in vitroDanice Wilkins1, Kory Alderson1, Myriam Bouchlaka1,Doug Redelman1, Lisbeth Welniak2, William Murphy2.1University of Nevada School of Medicine, Reno, NV;2University of California Davis, Sacramento, CA

We have previously demonstrated that immunotherapywith an agonist CD40 antibody in combination with IL-2results in synergistic CD4-indenpendent anti-tumor effects,but actually impairs the ability to generate an antigen-specific response. In the present study, our goal was toexamine the role of antigen specificity in the efficacy of anti-CD40 and IL-2 immunotherapy. Due to the massive CD8+Tcellexpansion that occurs after this regimen in both normal andtumor-bearing mice, we hypothesized that the anti-tumoreffects resulting from immunotherapy are due to theinduction of antigen specific T cells, as well as the increased