Naive antibody

Antibodies with affinities comparable to those obtained using traditional hybridoma technology can be selected from large naive antibody libraries, and the affinity of these can be further increased, to levels unobtainable in the immune system, by using the selected antibodies as the basis for subsequent libraries and selection. 

Fig. 10.5. Immunoblotting analysis of the antibody response of jirds against various stages of A viteae. (A) Reaction with sera of jirds vaccinated with irradiated L3 (B) reaction of sera of A. w feae-infected jirds (C) reaction with sera of naive jirds. 1, Male antigens 2, female antigens 3, mf antigens 4, L3 antigens. Note that the reaction of vaccinated jird sera is predominantly directed against chitinase bands of 205 kDa and 67 kDa (arrows) as well as against a 17 kDa protein.

It has already been noted that the phenotype of an acquired immune response is considered to reflect the early cytokine environment in which naive CD4+ T cells interact with antigen. Again, it has been suggested, for example, that early exposure to IL-4 can push an immune response in a Th-2 direction (Swain et al., 1990). We therefore investigated (by ELISA) whether ES-62 was able spontaneously to induce IL-4 secretion in naive murine spleen cells (48 h exposure). Ironically, given that the molecule induces a Th-2 antibody response and seems to be able to induce the release of a number of other cytokines, IL-4 was not detected (Harnett et al., 1999a). It was noted, however, that IL-4 was produced by spleen cells from mice that had been pre-exposed to ES-62. This established Th-2 phenotype is consistent with the antibody data. 

The conventional rabies vaccine was administered to the nine initially naive subjects seven days after completing the oral vaccination. Three of these volunteers produced neutralizing antibodies against rabies virus, although none of the five control subjects did. This study showed a clear indication that the orally delivered rabies vaccine has potential as an oral booster for the conventional rabies vaccine. 

Willats WGT, Gilmartin PM, Mikkelsen JD, Knox JP. Cell wall antibodies without immunization generation and use of de-esterified homogalacturonan block-specific antibodies from a naive phage display library. Plant J. 1999 18 57-65. 

Figure 1.7. Lymphocyte activation. When naive lymphocytes first encounter the antigen that is recognised by their receptor, they are stimulated to differentiate and proliferate. This clonal expansion is aided by the production of cytokines. Two cell types develop from this process the effector cells (i.e. either antibody-secreting plasma cells or cytotoxic T cells) and memory cells. Both cell types possess virtually the same receptor that was expressed on the naive lymphocyte.

DCs were generated (BmDC) from thigh bone marrow of naive C57BL/6 mice according to established procedures. In a spleen cell mixture of the same mice breed, DCs were identified using a fluorescent antibody. 

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