Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Complement Fixation Tests”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed1975

Diagnosis of bovine respiratory syncytial virus infection by complement fixation test.

The complement fixation test by the microtiter method was applied to the serological diagnosis of bovine respiratory syncytial (RS) virus infection. When used as complement fixing antigens, untreated infected cell culture fluid, fluorocarbon-treated, and ether-treated materials showed no differences in antigenicity among them. The complement fixing antigenicity of bovine RS virus appeared in bovine kidney and Vero cell cultures for the first time 4 days after inoculation. Both the infectivity and complement fixing antigenicity reached a maximum 6 days after inoculation. In detecting complement fixing antibody from infected cattle, the most outstanding specific reaction was obtained when 5% fresh normal calf serum had been added to the diluent of complement. Neutralizing and complement fixing antibodies were examined in serum samples from two cattle in the course of experimental infection. It was found that both antibodies turned to be positive 2 weeks after inoculation. There was a linear correlation between neutralizing and complement fixing antibody titers, when serum samples from 40 natural cases were tested in the acute and convalescent stages. In addition, common antigenicity was demonstrated between the virus of bovine origin and the Long strain of human RS virus by complement fixation test.

Animals↗
PubMed1976

The value of the skin test and complement fixation test in the diagnosis of chronic pulmonary histoplasmosis.

Histoplasmin skin test results in patients with chronic pulmonary histoplasmosis from Missouri and Texas were compared to results in a previous study of U.S. Navy recruits. When consideration was given to geographic areas from which persons from each group were admitted to the study, it was found that the recruits were as likely to have a positive skin test as were those with the disease. In a similar manner, the Texas histoplasmosis patients were compared to groups of patients from that state with chronic obstructive pulmonary disease and with pulmonary tuberculosis. Again, no significant differences were found. It was concluded that the histoplasmin skin test is not of value in the diagnosis of chronic pulmonary histoplasmosis. Histoplasmosis complement fixation test data from the chronic pulmonary histoplasmosis group were compared to data from the chronic obstructive pulmonary disease and pulmonary tuberculosis groups. The usefulness of the complement fixation test in chronic pulmonary histoplasmosis is limited, as with any test, by false-positive and false-negative reactions. A decision theory method was used to define the limits of usefulness.

Chronic Disease↗
PubMed1978

Evaluation of purified H and M antigens of histoplasmin as reagents in the complement fixation test.

Complement-fixation (CF) tests were performed with purified H and M antigens, histoplasmin, and Histoplasma capsulatum whole cell yeast phase antigen using sera of 126 patients with proven or suspected histoplasmosis. Specific titers for either H or for M antibody were obtained with the individual purified antigens; the highest titers were comparable to those obtained with histoplasmin. However, in sera containing only anti-M antibody, the titers obtained with the purified M antigen were 2 to 16 times those obtained with the histoplasmin or yeast phase antigens. The CF test for either H or M antibody was 4 to 32 times as reactive as the agar-gel microimmunodiffusion test; in general precipitin lines were obtained with either H or M antigens from sera with CF titers greater than or equal to 8. With sera containing H antibody, there was an excellent correlation between the CF titers obtained with purified M antigen and histoplasmin. The correlations of CF titers with H antigen and either histoplasmin or yeast phase antigen were very low.

Antibodies, Fungal↗
PubMed1979

The complement fixation test and African trypanosomiasis. II. The complement fixation test as an aid for assessing therapy.

Complement-fixing antibody titres decline after successful treatment of trypanosoma infected cattle during a fixed period. For investigating the practicability of the resulting double test procedure in the field, cattle under controlled drug regimes were tested at treatment and again 3 weeks later. Alternatively, the results from groups of treated and untreated animals from the same area were compared. Both serological and parasitological test results indicated an insuffieicnt effectiveness of therapy in the area under investibation.

Animals↗
PubMed1978

Studies on the immunogenicity of protamines in humans and experimental animals by means of a micro-complement fixation test.

A complement fixation study with human, monkey and rabbit sera, using purified sperm nuclear basic proteins as antigens, led to the following conclusions. (1) Protamines, the sperm-specific basic nuclear proteins, may be immunogenic in mammalians. (2) Antibodies detected in the indirect immunofluorescence test on human swollen sperm heads in sera from infertile and vasectomized men, are directed primarily against human protamines. (3) The results obtained suggested that differences in the immunization site and/or in the configuration of the immunizing protamine, may lead to the formation of antibodies directed against different antigenic determinants. Autoimmunity to protamines, following vasectomy or in infertile men, is accompanied by the formation of antibodies cross-reacting with common antigenic determinants present in protamines of other species. Induction of immunity to protamines by means of immunization with protamines-RNA complexes (in rabbits), or protamine-insulin complexes (in humans), leads to the formation of antibodies reacting more specifically with the immunizing protamine, showing only slight cross-reaction with other protamines. (4) The histone-like fraction present in mature human spermatozoa is composed mainly of histone fraction H2B.

Animals↗
PubMedDate not supplied

[The use of hemagglutination inhibition tests and complement fixation tests for evaluation of immunity states and diagnosis of recent rubella infections].

Comparative HAI and CF study of German measles antibodies in 575 sera collected from subjects of different age gave positive HAI reactions in 87% of the cases and positive CF reactions in 55% of the cases. The greater sensitivity of HAI and the longer presence of these antibodies justifies the use of this test for investigating the state of immunity in German measles. The combined use of the two tests for the diagnosis of the disease is very useful especially when the first serum sample is collected some time after the onset when the increase in serum antibody titers can only be demonstrated by CF, as HAI antibodies reach a high titer soon after the onset.

Antibodies, Viral↗
PubMed1979

Comparative sensitivity of a cultural test and the complement fixation test in the diagnosis of adenovirus ocular infection.

The sensitivity of human embryonic kidney (HEK) cell culture and the complement fixation test (cft) in the diagnosis of adenovirus ocular infection has been compared. The optimum time for collection of specimens to obtain the best results by each test has been examined. Sixty-one (53%) of 116 patients with moderate to severe follicular conjunctivitis, clinically indicative of adenovirus infection, had serological evidence of infection or had the virus isolated from ocular swabs. Virus was isolated from 53 patients (45%) and significant antibody rises were found in 33 (27%). When each test was carried out under optimum conditions, virus was isolated from 82% of cases and serological evidence of infection found in 72%. Serological responses as detected by the CFT appeared to be inferior in infections caused by adenovirus type 7 to those encountered in infections due to adenovirus types 3 and 8.

Adenoviridae Infections↗
PubMedDate not supplied

[Serological diagnosis of toxoplasmosis: comparative evaluation of the Sabin-Feldman, indirect immunofluorescence and complement fixation tests].

The AA. compared the indirect immunofluorescence test (IFI), with dye test and complement fixation test (CFT), used in diagnosis of Toxoplasmosis. CFT sensitivity is slightly inferior to that of dye test and IFI; the later give strictly similar results especially at medium and high titers; IFI is more readily and safety performed and easier to interpret.

Antibodies, Bacterial↗
PubMed1975

A mechanism for prozone formation in the complement fixation test for bovine brucellosis.

Complement fixation (CF) by bovine IgG1 or IgM antibodies to Brucella abortus was inhibited by specific non-complement-fixing antibodies of the IgG2 subclass. This inhibition may account for the appearance of prozones in CF titrations of some antiserums, and for the occurrence of serums which are positive to the Rose Bengal test, but negative to the CF test.

Agglutination Tests↗
PubMed1976

A study of the complement fixation test in Salmonella dublin infection.

The complement fixation test was evaluated in a study of Salmonella dublin infection in cattle. In calves vaccinated with a live S dublin vaccine at three days of age, complement fixing (CF) antibodies were not detected in colostrum-fed calves although CF antibodies were detected at low titre in colostrum-deprived calves. In calves vaccinated at three months of age and in experimentally infected cows, CF antibodies persisted for three to six months but serum agglutinin (SA) antibodies persisted at diagnostic titres for longer periods. When serum samples from outbreaks of S dublin infection were examined, the CF results were in agreement with the SAT in the majority of samples obtained from adults and calves suffering from enteric disease. In samples from cases of S dublin abortion, a number of samples had negative CF titres although the SA titres were indicative of infection. Non-specific CF reactions occurred in serum samples from cattle infected with salmonella serotypes other than S dublin.

Agglutination Tests↗
PubMed1976

Comparison of immunodiffusion and complement fixation tests in the diagnosis of histoplasmosis.

The immunodiffusion and complement fixation tests for histoplasmosis were compared on 2,090 initial sera from 70 proven cases of histoplasmosis, 177 routine chest hospital patients, and 1,843 coal miners from outside the major endemic area for histoplasmosis. The complement fixation test using histoplasmin as antigen detected antibodies in the sera of 72.8% of the 70 proven cases, while the complement fixation test using yeast antigen detected antibodies in 94.3% of the case sera, and the immunodiffusion test using histoplasmin antigen detected antibodies in 90% of the sera. The tests were also compared for sensitivity, specificity, and ease of performance.

Antibodies, Fungal↗
PubMed1977

Demonstration of antibodies to soluble nuclear antigens by complement fixation test. An application of microtiter technique.

The complement fixation test utilizing the microtiter system was applied to study sera from patients with a variety of connective tissue diseases for the presence of antibodies to soluble nuclear antigens. A good correlation was found between microtiter complement fixation and hemagglutination for anti-RNP and anti-Sm antibodies. Anti-Ha antibodies were detected by complement fixation but not by hemagglutination. Different enzyme digestions of the soluble nuclear antigen prior to assay and use of a quantitative microcomplement fixation test were found to improve the analysis of sera with multiple antibodies.

Animals↗
PubMed1976

Studies on the origin of false positive reactions to the complement-fixation test for contagious bovine pleuropneumonia.

Serums of cattle free from contagious bovine pleuropneumonia (CBPP) were tested in complement fixation (CF) tests using 3 antigens; these were the standard antigen (SA) used to test to CBPP in Australia, an ethanol extract antigen (EA) also prepared from Mycoplasma mycoides subsp. mycoides (M. mycoides) and an antigen prepared from a Group 7 bovine mycoplasma isolated from arthritis (AA). The serums included 146 which fixed complement with SA. Eighty percent of these false-positive serums reacted with AA but not with EA; the other 20% were positive at low titre with EA but gave no reaction with AA. Attempts were made to produce false-positive serums experimentally by inoculating 3 Group 7 mycoplasmas and 2 Mycoplasma bovigenitalium strains into cattle. Serums from 3 of 9 cattle inoculated with strain L2917 (Group 7) reacted with SA but differed from the false-positive serums of field cattle by reacting with all 3 antigens. Tests with serums from cattle experimentally infected with CBPP gave similar titres with SA and EA, but the results with AA were mostly negative or less than 10% of the titres obtained with SA and EA. The results of CF tests on serums from the experimental cattle, after absorptions with suspensions of the mycoplasmas, showed that there was a one-way serological relationship between strain L2917 and M. mycoides and between this Group 7 strain and M. bovigenitalium. The CF tests with 3 antigens have assisted in demonstrating the false-positive nature of the reacting field serums encountered in the course of routine CF tests for CBPP in cattle in Australia.

Absorption↗
PubMed1976

[Use of indirect complement fixation test for studying foot and mouth disease virus].

The indirect complement-fixation test was used in experiments for the subtype differentiation, and with the agar gel diffusion and the serum neutralization test was studied the immunity in cattle that had already recovered from foot-and-mouth disease or were immunized against the disease. It was found that the indirect complement-fixation test is instrumental in the demonstration of the antigenic differences between the foot-and-mouth viruses. Comparative experiments have shown that the indirect test in this case is more expedient and of higher economic value than the direct CF reactions after Traub and Möhlmann and after Marucci. The assessment of the results of comparative investigations of sera carried out by the indirect complement-fixation test, the agar gel diffusion test, and the serum neutralization reaction revealed that the indirect reaction is a convenient, quick, and prompt method of work. Discussed is the sensitivity of the reaction and its advantages and its advantages in studies on a large scale on the immune status of animals immunized against F.M.D. or animals that have recovered from the disease.

Animals↗