Oral Presentations - Federation of Clinical Immunology Societies

S36 Abstracts
values for antibody levels post-immunization. Serotypes 14,
9V, and 4 appear high to low in hierarchy of responses.
Discussion: Third generation multiplex assays for SSAPAb
levels, without cross-reacting antibodies as confounders,
indicate normal ranges after immunization are serotype
specific with evidence of hierarchy and diversity. These data
are consistent with serotype specific and non-specific pathways
in antibody responses to pneumococcal capsular
polysaccharides.
doi:10.1016/j.clim.2007.03.278
F.66 Differential Cytokine Response Induced by
M. Avium and M. Abscessus in Human Macrophages
is Mediated Through p38 MapKinase Signalling
Pathway and Partially Dependent on TLR2
Activation
Elizabeth Sampaio, Senior Visiting Investigator, NIAID,
NIH, Bethesda, MD, Houda Elloumi, Postdoctoral Fellow,
NIH/NIAID, Bethesda, MD, Adrian Zelazny, Staff Scientist,
NIH/NIAID, Bethesda, MD, Yvonne Shea, Laboratory
Supervisor, NIAID/NIH, Bethesda, MD, Li Ding, Lab
Manager, NIAID/NIH, Bethesda, MD, Steven Holland, Lab
Chief, NIH/NIAID, Bethesda, MD
Non-tuberculous mycobacteria (NTM) are ubiquitous
environmental organisms that can cause chronic lung
infection associated with primary or acquired immune
deficiencies or in otherwise apparently normal individuals.
Among NTM, M. avium is the most common cause of
mycobacterial infection. Moreover, M. abscessus is an
emerging pulmonary pathogen responsible for the majority
of infections by rapidly growing mycobacteria. It has been
shown that the ability of mycobacteria to induce TNFα
secretion is inversely related to their virulence. In this
work, cytokine response and signaling pathways triggered
by reference and clinical isolates of M. abscessus and M.
avium (5 smooth and 5 rough morphotypes) were assessed
in human PBMCs and monocytes. Mycobacteria-induced
TNFα response is enhanced for M. abscessus (8535
±1010 pg/ml) as compared to M. avium (2400±244 pg/
ml, pb0.017) and no major differences were noted when
compared colony morphologies within the same species.
All mycobacterial strains were able to activate p38 MAP
kinase phosphorylation and NF-kB translocation. Induction
of TNFα was dependent on p38 MAPK signaling pathway
since pre-incubation of cells with the p38 signaling
inhibitor (SB203580) led to N80% reduction in cytokine
secretion. In addition, treatment of cells with anti-human
TLR2 antibodies showed TLR2 to be at least partially
involved in signaling for M. abscessus as well. The present
data indicate that M. avium is a more virulent pathogen
than M. abscessus and elicits limited activation of cellular
effector mechanisms, thereby escaping elimination.
Accordingly, lung disease induced by NTM in nonpredisposing
individuals may be associated with a yet uncharacterized
underlying genetic defect.
doi:10.1016/j.clim.2007.03.279
F.67 Characterization of the Cellular Immunity in
Patients Presenting Extensive Dermatophytoses Due
to Trichophyton Rubrum
Dewton Moraes Vasconcelos, MD, PhD, Department of
Dermatology, University of São Paulo Medical School, São Paulo,
Brazil, Anna Cristina Collanieri, BSc, Department of
Dermatology, University of São Paulo Medical School, São Paulo,
Brazil, Mauricio Domingues Ferreira, MD, PhD, Department of
Dermatology, University of São Paulo Medical School, São Paulo,
Brazil, Tatiana Negri Santi-BSc, Department of Dermatology,
University of São Paulo Medical School, São Paulo, Brazil, Anete
S. Grumach, MD, PhD, Department of Dermatology, University
of São Paulo Medical School, São Paulo, Brazil, Alexandre
Almeida, MD, MSc, Department of Dermatology, University of
São Paulo Medical School, São Paulo, Brazil, Alberto Jose da
Silva Duarte, MD, PhD, Department of Dermatology, University
of São Paulo Medical School, São Paulo, Brazil
Background: Dermatophytes cause infection in humans
independent of the immunological status of the patient. In
common to other infections the clinical features differ in
immunodeficient patients. Dermatophytoses in cellular immunodeficient
patients are usually less inflammatory, but some
patients present pustular extensive lesions, frequently with
follicular involvement.
Objectives: Obtaining a reliable antigen by growth and
purification of T. rubrum and to evaluate the immune
reactivity “in vitro”, and quantify the immune response to
the peptide YIIDTGIDID of T. rubrum. Methods: The fungal
samples were obtained from the fungal library of the Institute
of Tropical Medicine for antigen preparation, and the peptide
was synthesized by EvoQuest. The lymphoproliferation assay
was performed by tritiated thymidine incorporation and the
cytokine quantifications by ELISA of culture supernatants.
Results: The antigenic extract was efficient in the stimulation
of cell cultures. The response to the peptide was also efficient
and highly specific in sensitized controls. Despite most
patients presented deficient responses, some presented
normal lymphoproliferation. There was no difference
between the cytokine secretion among patients and controls.
doi:10.1016/j.clim.2007.03.280
F.68 Evaluation of Cellular Responses to Rotavirus
and NSP4 in Children during Natural Rotavirus
Infection
Jyoti Logani, Research Officer, Department of Pediatrics, All
India Institute of Medical Sciences, New Delhi, India, Santosh
Gupta, Research Associate, Department of Pediatrics, All India
Institute of Medical Sciences, New Delhi, India, Shinjini
Bhatnagar, Scientist, Department of Pediatrics, All India
Institute of Medical Sciences, New Delhi, India, Pratima Ray,
Scientist, Department of Pediatrics, All India Institute of
Medical Sciences, New Delhi, India, M.K. Bhan, Department of
Pediatrics, All India Institute of Medical Sciences, New Delhi,
India
Rotavirus (RV) is a major cause of gastroenteritis in young
children leading to ∼611,000 deaths annually. Further