ABSTRACT
This study is designed to evaluate the immune status of schoolchildren with respect to Streptococcus pyogenes, and to ascertain the usefulness of antideoxyribonuclease B (ADNase B). Antistreptolysin O (ASO) and ADNase B concentrations were measured quantitatively in 266 serum samples from healthy elementary school children in Seoul. Simultaneously, throat cultures were taken in order to isolate S. pyogenes and other beta-hemolytic streptococci (BHS). The upper limits of the normal (ULN) concentration of ASO and ADNase B were 326 IU/mL, and 362 IU/mL, respectively. The correlation between ADNase B (y) and ASO (x) was y=0.4x+173 (r= 0.46). Mean ADNase B level (392 IU/mL) was significantly higher in children with S. pyogenes than in those with non-group A BHS (236 IU/mL) or no BHS (234 IU/ mL). Some schoolchildren were proven, via ASO and ADNase B tests, to be harboring asymptomatic S. pyogenes infections. The high ULN of ASO and ADNase B in schoolchildren should be carefully considered, in order to interpret the data collected from the patients. We could add the ADNase B test to our set of diagnostic tools, which would allow us to more accurately detect and diagnose streptococcal infections, as ADNase B was more specifically related to the results of throat cultures, and there was little correlation between ASO and ADNase B.
Subject(s)
Child , Female , Humans , Male , Antibodies, Bacterial/blood , Bacterial Proteins/immunology , Deoxyribonucleases/immunology , Korea , Serologic Tests , Streptococcal Infections/diagnosis , Streptococcus pyogenes/enzymology , Streptolysins/immunologyABSTRACT
The upper limit of normal values of group A streptococcal antibodies should be known for a population concerned because it is influenced by many local conditions. As yet the reference value of the these antibodies has not been determined by using a quantitative method among Bangladeshi children. We determined the reference value of anti-streptolysin O and anti-deoxyribonuclease B among 361 apparently healthy rural Bangladeshi primary school children (aged 5 to 14 years, mean 9.2 years). Anti-streptolysin O was measured by an auto-analyzer and antideoxyribonuclease B was measured by microtitre method. The geometric mean titres for the entire group was 241 IU/ml and 222 IU/ml for anti-streptolysin O and anti-deoxyribonuclease B respectively. The upper limit of normal values (80th percentile) was 390 and 340 for anti-streptolysin O and anti-deoxyribonuclease B, respectively. These limits should be of value to physicians, epidemiologists and clinical laboratory personnel as well.
Subject(s)
Adolescent , Antibodies, Bacterial/blood , Bacterial Proteins , Bangladesh , Child , Child, Preschool , Deoxyribonucleases/immunology , Female , Humans , Male , Reference Values , Rural Health , Streptococcus pyogenes/immunology , Streptolysins/immunologyABSTRACT
The report that gelonin cross-linked with monoclonal antibodies with the use of 2-iminothiolane (2-IT) exhibited higher cytotoxicity than the conjugates prepared with the use of N-succinimidyl-3-(2-pyridylthio) propionate (SPDP) alone, has prompted us to investigate the effect of epsilon-NH2 group modification with 2-IT on the ribosome-inactivating property (RIP) of gelonin. The purified gelonin was modified with 2-IT at a different molar ratio and their effects on immunoreactivity and ribosome-inactivating property were compared with those of N-succinimidyl 6-[3-(2-pyridyldithio) propionamido] hexanoate (long chain-SPDP) and SPDP modified gelonin derivatives. Modification of single amino group with 2-IT results in about 25-50% inhibition of immunoreactivity and 60-70% loss of protein synthesis inhibition activity. Modification of 2-3 amino groups further hampers both immunoreactivity and protein synthesis inhibition property of gelonin. Both the long chain-SPDP with SPDP modifications showed more pronounced effects on immunoreactivity and RIP activity as compared to the similar ratio of 2-IT modification(s). It may, therefore, be concluded that the positive charge plays an important role in the immunological as well as the protein synthesis inhibitory effect of gelonin.
Subject(s)
Antigens/immunology , Cell-Free System , Cross-Linking Reagents/metabolism , Deoxyribonucleases/immunology , Imidoesters/metabolism , Lysine/chemistry , Plant Proteins/chemistry , Protein Synthesis Inhibitors/chemistry , Ribosome Inactivating Proteins, Type 1 , Ribosomes/drug effects , Succinimides/metabolismABSTRACT
Mice are susceptible to natural infections with streptococci and therefore can serve as suitable animal models to study experimental streptococcal infections. In an earlier study, we had shown the development of pharyngeal colonization, antibody response and histopathological changes in the heart following intranasal (IN) challenge with a rheumatogenic serotype of group A beta haemolytic streptococcus, the M type 18. To determine if nonpharyngitis associated serotypes can also elicit similar responses, 30 Swiss albino mice were challenged intranasally with 2 x 10(7) colony forming units of a skin associated serotype of group A beta haemolytic streptococcus, the M type 49. Pharyngeal colonization varied from 64% (n = 30) in the first week to 69% (n = 16) during the fourth week after IN challenge. Eleven (36.7%) of the 30 animals studied showed antibody response to DNase B (ADNB) with peak titers varying from 150 to 1200 units. Wide variations were seen in ADNB titers in individual mice. Histopathological evidence for cardiac lesions were seen in three animals. The changes were mild and varied from mild to chronic endocardial inflammation to calcification. The study shows that Swiss albino mice are also susceptible to IN challenge with skin associated strains of GABHS and therefore can serve as useful models to study the effects of experimental infection with diverse serotypes of GABHS.
Subject(s)
Administration, Intranasal , Animals , Antibodies, Bacterial/blood , Deoxyribonucleases/immunology , Disease Models, Animal , Endocarditis, Bacterial/etiology , Mice , Serotyping , Streptococcal Infections/etiology , Streptococcus pyogenes/classificationABSTRACT
Swiss albino mice from a randomly bred colony were inoculated intranasally with 1.6, 2 or 2.4 x 10(7) colony forming units of a mid-logarithmic phase culture of group A beta haemolytic streptococcus M type 18 for 3 days, 6 days or once a week respectively for three weeks. Pharyngeal colonisation could be observed in 67 (59.8%) of 112 mice on 4th day after inoculation and 14 (38%) of the 37 mice on 21st day. Out of 27 mice tested for determination of antibodies to deoxyribonuclease B at regular intervals for 98 days, 15 (55.5%) showed responses, with maximum titers varying from 50 units to 4800 units in individual mice. Histopathological evidence for cardiac lesions were seen in five (3.03%) of the 165 animals studied. These included one case of severe endocarditis, two cases of endocarditis with valvular lesions and one case with non-specific lymphocyte infiltration in the heart. One other animal showed subendocardial oval nodular aggregates. Although the cellular nature of these lesions were not determined, this study shows that Swiss albino mice can serve as suitable animal models to study experimental streptococcal infections. However these are preliminary observations and are to be confirmed and revalidated by further controlled experiments.
Subject(s)
Animals , Deoxyribonucleases/immunology , Heart/microbiology , Mice , Myocardium/pathology , Pharynx/microbiology , Streptococcus pyogenes/immunologyABSTRACT
Streptococcus pyogenes es una bacteria conocida desde hace más de un siglo por los médicos. En la última década se ha presentado con un nuevo rostro asociado a cuadros clínicos invasores con una alta mortalidad. En el presente artículo se describe al agente, se clasifican estos cuadros clínicos, se discuten su etiopatogenia, tratamiento y prevención