SYNOPSIS OF SMITH’S RESEARCH INTERESTS

Areas of Research and Teaching Expertise:

Comparative Immunology, Medical Microbiology and Molecular Biology

Research Focus:

· Evolution of nonspecific immunity, focusing on the proteins and genes of the complement system. The role of complement in the regulation and modulation of innate and adaptive immune responses.

· Isolation and characterization of antibacterial proteins/peptides from the nurse shark.

· Alternative/complementary medicine: Study of the effect of shark cartilage on innate and adaptive human immune function

Experimental Animal: Nurse shark, Ginglymostoma cirratum.

SHARK COMPLEMENT

1. Elucidation of complement activation pathways in the nurse shark, Ginglymostoma cirratum: gene cloning, characterization of complement proteins and study of biological function(s), i.e., immunemodulation, opsonization, target lysis, anaphylatoxins, receptor/ligand interaction

Projects in progress:

· Cloning genes encoding complement proteins (focus on C3, factor B, factor D) of the alternative pathway

· Activation cleavage and control of C3 activity

· Study of factor B/C2 activity

· Characterization and composition of shark MAC (membrane attack complex)

· Study of shark complement-derived opsonins and anaphylatoxins

· Characterization of shark complement control proteins: factors I and H

2. Comparative Studies in Complement Evolution

· In search of the primordial ancestor of C3/C4/C5

· Identification of the point of divergence of factor B and C2

· Evolution of MAC

SHARK ANTIBACTERIAL FACTORS

· Isolation and characterization of antibacterial proteins/peptides from shark leukocytes

IMMUNOMODULATION PROPERTIES OF SHARK CARTILAGE (Invitro studies)

· Induction of signal molecules, such as cytokines and growth factors

· Affect on cell processes such as phagocytosis, apoptosis, proliferation and cell migration (chemotaxsis)

Research activities in the laboratory routinely involve electrophoretic analysis of RNA and DNA, plasmid isolation and purification, amplification by PCR, 3’ and 5’ RACE, cloning, screening of cDNA libraries, Southern and Northern blotting, gene sequencing, computer-assisted phylogenetic analyses, microarray procedures, protein purification using low and high liquid chromatography, SDS-PAGE, Western blotting, cell separation procedures, in vitro cell cultures, ELISA, and functional assays (phagocytosis/oxidative burst, chemotaxis, cell proliferation, complement activity etc).

Representative Publications:

Hyder Smith, S., Obenauf, S. and Smith, D.S. (1989) Fine structure of shark leukocytes during chemotactic migration. Tissue & Cell 21 (1), 47‑58

Obenauf, S. and Hyder Smith, S. (1992) Migratory response of nurse shark leucocytes to activated mammalian sera and porcine C5a. Fish & Shellfish Immunol. 2, 173‑181.

Smith, S. L. (1998) Shark Complement: An Assessment. Immunol. Revs, 166 67-77

Dodds A.W., Smith, S. L., Levine, R.P. & Willis, A.C. (1998). Purification and initial characterization of complement components C3 and C4 of the nurse shark (Ginglymostoma cirratum) and the channel catfish (Ictalurus punctatus). Developmental & Comparative Immunol 22, 207-216

Nonaka, M. and Smith, S. L. (2000) Complement system of bony and cartilaginous fish. Fish & Shellfish Immunol. Fish & Shellfish Immunology 10, 215-228

Terado, T., Smith, S.L., Nakanishi, T., Nonaka, M., Takemoto, T., Kimura, H. and Nonaka, M. (2001) Structural specialization of the serine protease domain of complement factor B at the emergence of jawed vertebrates. Immunogenetics 53: 250-254

Abstracts

Hinds, N, Smith, S.L., and Smith, V.J. (2001) Antibacterial activity of shark leukocyte lysates. The FASEB J. 15: A692

Dishaw, L., Smith, S.L. and Bigger, C. (2001) Sequence and phylogenetic analysis of partial cDNA clones from a coral, encoding a thiol-ester-containing A2M/C3-like protein. 15:

Moffat, B., Willis, A.C., R.B. Sim and Smith, S.L. (2001) Complement regulatory protein factor H in shark and carp. The FASEB J. 15: