Study Of Antibody Levels Research Articles

Titres of specific antibodies to poliovirus type 3 and tetanus toxoid in saliva and serum of children with recurrent upper respiratory tract infections.

A study of antibody levels (in saliva and blood) against common vaccine antigens was performed in a population of 32 children suffering from recurrent upper respiratory tract infections (URTI). None of the patients had primary or secondary immunodeficiency syndromes or other known predisposing factors for respiratory diseases. Titres of the isotype-specific antibodies immunoglobulin A (IgA), immunoglobulin M (IgM), and immunoglobulin G (IgG) against two vaccine antigens--poliovirus type 3 (P3) and tetanus toxoid (TT), a viral antigen and a bacterial antigen, respectively--were measured in unstimulated saliva and serum, both in patients and in 24 healthy children (controls), by using a standard enzyme-linked immunosorbent assay (ELISA). In addition, levels of total IgA and avidity of IgA antibodies to both P3 and TT in saliva were evaluated. No difference was found between patients and controls as to levels of total IgA, or specific IgA and IgM antibodies against both P3 and TT in saliva. Furthermore, the avidity of salivary IgA antibodies against the two antigens did not differ between the two populations. However, the average concentrations of saliva-specific IgG antibodies to both the viral and the bacterial antigen were significantly lower (p <0.01 for P3 and p <0.05 for TT, respectively) in saliva of children with recurrent URTI, whereas no difference was found in serum for any immunoglobulin isotype determined compared with healthy individuals. The results of the present study provide suggestive evidence for the existence of subtle IgG-restricted defects in antibody responses at the mucosal level, but not at the serum level, in some children with undue susceptibility to URTI.

A study of antibody levels in wild ruminants vaccinated against rabies.

The authors have vaccinated 22 fallow deer (Dama dama) and 10 mouflons (Ovis ammon musimon) against rabies with an inactivated vaccine: 4 fallow deer with 1 ml, 14 fallow deer and 10 mouflons with 2 ml, 4 animals were kept as controls (fallow deer). The antibody responses were checked by fluorescent foci inhibition carried out on blood samples collected during a two-year period. All the animals developed antibody titres and were still protected after 24 months.

Study of antibody levels in children with purulent otitis media.

A series of episodes of acute otitis media were studied with reference to the bacterial findings in the nasopharynx and the specific antibody response in a group of children nine months to ten years of age, with previous frequent episodes of acute otitis media, Serum IgG, IgM and IgA antibody levels against five polysaccharide antigens, namely Haemophilus influenzae type b and Streptococcus pneumoniae types 3, 6, 19 and 23, were studied by means of an enzyme-linked immunosorbent assay. The selection of polysaccharide antigens was based on isolation frequency. The sera to be tested were tenfold serially diluted. An extinction of 0.2 over the base was taken as the end-point titer and expressed as in-log10. The results showed that most children including those under three years of age showed increasing homologous antibody titers at an infection, or had already initially very high antibody titers, especially of the IgG class. The titers reached levels of 10(4) to 10(5). In some cases, however, it could be shown that high serum antibody titers did not give protection against a new infection with the same serological type of bacteria. It was also demonstrated that most children, regardless of age, had IgG and IgM titers against the heterologous antigens. In some cases the levels were quite high (10(3) to 10(4)). However, the IgA antibody levels were lower and in a considerable number of samples antibodies were not even detectable.

A Study of Antibody Levels in the Young Pig

SUMMARY A period of low antibody level against the ‘O’ mid ‘K’ antigens of certain strains of Escherichia coli, was demonstrated in the sera of pigs during the third week of life, following the decline of passively acquired antibody from the dam and preceding active antibody production by the pig itself. ‘K’ antibody was found in fairly high levels in the intestinal contents and faecal extracts of young pigs only. There appeared to be a difference in the degree of absorption of ‘O’ and ‘A’ antibody from the intestines of newborn pigs.

Studies of the Epidemiology of Influenza as Demonstrated by Serum Pools

In a previous publication1we reported the results of a study of individual cases of influenza infection in the St. Louis area extending from 1943 to the period just prior to the onset of the Asian Influenza epidemic in 1957. Information was presented concerning the prevalence of the disease during each year and the antigenic characteristics of the strains of virus responsible for the outbreaks that were observed. In many virus infections, such as poliomyelitis, it is known that for each case with clinical manifestations of disease there are many inapparent infections. The occurrence of inapparent infections in the case of influenza is obvious if it can be shown that an increase in antibodies against the prevalent strain of influenza virus occurs in the general population simultaneously with the recognition of clinical cases. It was felt that a study of antibody levels in large pools of unselected sera might