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C J Lobb

Publications and source records attributed to C J Lobb.

42 records · Page 3Linked to original sources
PubMed1981

The metabolic relationships of the immunoglobulins in fish serum, cutaneous mucus, and bile.

Passive administration of homologous, radioiodinated, purified high m.w. (HMW) or low m.w. (LMW) serum immunoglobulin (Ig) into the sheepshead, a marine teleost, showed that the LMW Ig was neither an extracellular precursor nor a degradation product of the HMW Ig. These studies also showed that the half-lives of the HMW and LMW Ig were statistically identical, i.e., approximately 16 days. Furthermore, this work demonstrated that the Ig found in cutaneous mucus and bile were not due to transudation or active transport of either the serum HMW or LMW Ig. The implications of these later findings, coupled with previous physicochemical characterizations of the Ig in fish secretions, support the hypothesis that fish, similar to higher vertebrates, have a secretory immune system.

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PubMedDate not supplied

Characterization of anti-hapten antibodies generated in vitro by channel catfish peripheral blood lymphocytes.

Secondary in vitro stimulation of channel catfish peripheral blood lymphocytes with haptenated T-dependent antigen (TNP-KLH) elicited large numbers of hapten-specific Ab-producing cells and relatively high levels (10-96 micrograms/mL) of TNP-specific Ab in the culture medium. These in vitro generated Abs were compared to in vivo generated Abs from the serum of the same fish with respect to covalent structure, affinity, and isotypic composition of heavy and light chains. SDS-PAGE analysis under both reducing and nonreducing conditions revealed that the in vitro Abs were structurally similar to the serum Abs. Similarly, in vitro pulse-labeled Abs also exhibited the eight band profile characteristic of channel catfish serum Abs when run under nonreducing denaturing conditions. Scatchard analysis of equilibrium dialysis data revealed that the affinities of the culture- and serum-derived Abs were quite similar, that is, exhibited association constants of approximately 2.0 x 10(6) M-1. However, it was routinely observed that the in vitro generated Abs exhibited somewhat fewer binding sites per molecule than those derived from serum. The use of murine monoclonal Abs specifically for different isotypes of channel catfish heavy and light chains demonstrated that the isotypic composition of the culture- and serum-derived fish anti-TNP Abs were similar; exceptions occurred with cultures producing lower levels of Abs. These results strongly suggest that channel catfish in vitro Ab responses closely reflect what normally occurs in vivo.

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PubMedDate not supplied

Immunoglobulin in the eggs of the channel catfish (Ictalurus punctatus).

Egg yolk proteins obtained from 2-3-day-old fertilized channel catfish eggs were analyzed to determine if immunoglobulin (Ig) was present. Using both monoclonal and polyclonal antibodies to catfish Ig, egg Ig was isolated and structurally characterized. The egg Ig when analyzed in SDS-gels under nonreducing conditions dissociated into eight distinct subpopulations with relative mobilities identical to that previously described for the serum Ig of the channel catfish. In addition, the component heavy (H) and light (L) chains of the egg Ig had similar relative mobilities as the H and L chains identified in serum Ig. Immunocytological studies using both polyclonal and monoclonal anti-catfish Ig showed that Ig was dispersed throughout the yolk of the egg. In addition these analyses indicated that Ig was localized within the external membranes (eggshell) of the egg.

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