James B. Campbell

Human adenovirus type 5 vectors expressing rabies glycoprotein

The prevalence of wildlife rabies throughout the world and the continued spread of this disease in North America highlights the need for oral vaccines which may be used safely and effectively to vaccinate a number of species that are reservoirs or vectors of rabies. We have previously shown that AdRG1, a replication competent recombinant human adenovirus type 5 (Ad5) expressing a rabies glycoprotein (RG), can induce immunity to rabies in rodent, canine, and skunk model systems. To improve the Ad5 vector system as a potential oral vaccine, we have constructed additional Ad5 recombinant vectors and compared RG expression in cell culture and immunogenicity in animals. Two new replication competent vectors are compared. AdRG1.3, which carries RG with accompanying SV40 poly A addition sequences within an E3 deletion, and AdRG4, which has RG in the E3 deletion but under the control of an exogenous Ad2 major late promoter, both express higher levels of RG in permissive cell culture than did AdRG1 and both elicit high levels of serum anti-rabies antibodies by parenteral or oral routes in animals. AdRG1.3 may be a more effective vaccine vector in species which are non-permissive for the replication of human Ad5.

Chiropractors and Vaccination: A Historical Perspective

Although there is overwhelming evidence to show that vaccination is a highly effective method of controlling infectious diseases, a vocal element of the chiropractic profession maintains a strongly antivaccination bias. Reasons for this are examined. The basis seems to lie in early chiropractic philosophy, which, eschewing both the germ theory of infectious disease and vaccination, considered disease the result of spinal nerve dysfunction caused by misplaced (subluxated) vertebrae. Although rejected by medical science, this concept is still accepted by a minority of chiropractors. Although more progressive, evidence-based chiropractors have embraced the concept of vaccination, the rejection of it by conservative chiropractors continues to have a negative influence on both public acceptance of vaccination and acceptance of the chiropractic profession by orthodox medicine.

Immunomodulatory Effects of Orally-Administered Saponins and Nonspecific Resistance against Rabies Infection

We present evidence that orally fed Quillaja saponins offer nonspecific resistance to mice against rabies viral infection. Adoptive transfer of spleen cells and thymocytes from animals preconditioned with saponin (SAP), inactivated rabies antigen (AG), or a mixture of AG+SAP has offered significant protection against an intracerebral challenge with live rabies virus. Levels of serum rabies-neutralizing antibodies in the different groups of recipient animals did not correlate with the respective survival rates. Culture supernatants of concanavalin A-stimulated spleen cells from animals fed SAP or AG+SAP induced marked T cell and B cell proliferation, and also greatly enhanced the plaque-forming cell activity of unprimed spleen B cells. Irrespective of the presence or absence of rabies-specific antibodies, sera from animals fed a mixture of AG+SAP induced significant levels of cell proliferation and augmented phytohemagglutinin (PHA)-induced responsiveness of spleen lymphocytes in vitro. The addition of sera from animals fed AG alone resulted in inhibition of cell proliferation and suppressed PHA-induced responses.

Attitudes towards vaccination among chiropractic and naturopathic students

We have investigated the attitudes towards vaccination of undergraduate chiropractic and naturopathic students in the two major complementary and alternative medicine colleges in Canada. While the majority of the students were not averse to vaccination, we found in both colleges that anti-vaccination attitudes were more prevalent in the later years of the programs. Reasons for this are discussed, and we provide suggestions for strategies to address the situation.

Observations on the determination of serum and red-cell folate levels by a radiometric assay method.

Our experience with the Bio-Rad Quanta-Count folate radioassay kit has revealed very good in-run precision and good day-to-day reproducibility in the assay of both serum and red-cell folate levels. Ascorbic acid is not required as folate preservative if blood samples are frozen within hours after collection. For the determination of red-cell folates, our data clearly show the need for maintenance of a certain level (6-8 gm%) of protein in the assay system. Protein (albumin or folate-free human serum) must be added to the red-cell lysate to compensate for the serum loss resulting from the high dilution factor necessary. In the absence of this added protein, red-cell values are markedly lower. A good correlation exists between red-cell folate values obtained from the assay of washed red cells and from the assay of whole blood with corrections for serum folate levels.