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At least 19 recordsLinked to original sources
PubMed1989

Immunoaffinity isolation and partial characterization of the Coccidioides immitis antigen detected by the tube precipitin and immunodiffusion-tube precipitin tests.

The antigen participating in the tube precipitin (TP) serologic test for coccidioidomycosis was isolated from mycelial-phase antigen (coccidioidin) by immunoaffinity and characterized by various analytical procedures. This was accomplished by first preparing the antigen-antibody precipitate by using antigen and human serum positive for TP (immunoglobulin M) antibody and then liberating the antigen by digestion with pronase. This protease destroyed the antibody and left the antigen intact as indicated by immunodiffusion-TP. The coccidioidal antigen was isolated from the proteolytic digest by using size exclusion chromatography. DEAE chromatography of this antigen yielded two fractions with immunodiffusion-TP reactivity which had average molecular sizes of 225 and 140 kilodaltons, respectively. The presence of carbohydrate and amino acids indicated that the antigen(s) is a glycopeptide. Compositional analysis showed that one fraction contained 3-O-methylmannose, mannose, and glucose in a ratio of 8:1.2:1, whereas the second fraction contained 3-O-methylmannose, mannose, glucose, and galactose in a ratio of 1:1:1:1. The amino acids glycine, alanine, serine, threonine, aspartic acid plus asparagine, and glutamic acid plus glutamine constituted 60 to 70% of the amino acids in both glycopeptides. Neither antigen could be detected entering the gel in sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Lectin affinity provided evidence of a high-mannose asparagine-linked glycopeptide in the first peak and an asparagine-linked glycopeptide with a biantennary complex-type structure in the second peak.

Amino Acids↗
PubMed1989

[Comparison of immunoenzymatic staining technique (IEST), double gluing strip circumoval precipitin test (DGS-COPT) and conventional circumoval precipitin test (CV-COPT) for diagnosis of schistosomiasis japonica].

IEST, DGS-COPT and CV-COPT using lyophilized ova of schistosoma japonicum were performed on sera from 120 cases of schistosomiasis japonica, 120 cases of schistosomiasis japonica 3-8 years after being cured with praziquantel and 120 healthy individuals by single-blind method. The sensitivity and specificity of IEST was 91.7% and 95.8% respectively which were significantly higher than that of both DGS-COPT and CV-COPT. The negative conversion rate of cured patients was 70.8% with IEST, 80.8% with DGS-COPT and 81.7% with CV-COPT. The results showed that IEST has higher diagnostic value for schistosomiasis than both COPT. DGS-COPT has the same diagnostic value as CV-COPT, however, it was easy to perform and time-saving, thus it might be applied in the fields for practical purposes.

Animals↗
PubMed1992

Precipitins and specific IgG antibody to Aspergillus fumigatus in a chest unit population.

BACKGROUND: The enzyme linked immunosorbent assay (ELISA) for detecting IgG antibodies to Aspergillus fumigatus is more sensitive than the measurement of Aspergillus precipitins. The relation of the results from both techniques to the clinical pattern of disease in a large unselected group of patients from a large referral centre is unknown. METHODS: The clinical relation of precipitins to Aspergillus fumigatus to clinical disease was determined retrospectively in 98 patients attending a primary referral centre. Precipitin results were compared with the specific IgG antibody to A fumigatus in 88 of the sera. Precipitins were determined by the agar gel double diffusion test and specific IgG antibody to A fumigatus by a quantitative ELISA. RESULTS: Precipitins were detected in the unconcentrated serum of 51 patients. Thirty nine of these had a mycetoma or allergic bronchopulmonary aspergillosis, 34 having specific IgG antibody to A fumigatus more than the control range. Forty seven patients had precipitins only after threefold concentration of serum or to only one of the four A fumigatus antigen extracts. Most of these had specific IgG in or near the control range. Thirty of these had A fumigatus skin test negative asthma or bronchiectasis, in which aspergillus was probably not pathogenic. There was a close relation between the level of antibody detected by the ELISA and the number of precipitin lines. CONCLUSIONS: This study reaffirmed the supportive role of aspergillus precipitins in the diagnosis of pulmonary aspergillosis. No additional benefit in the routine use of the ELISA was seen. It also showed that care should be taken in interpreting positive precipitin results from concentrated serum and that using several rather than one A fumigatus antigen extract is helpful for identifying allergic aspergillosis.

Antibodies, Fungal↗
PubMed1975

Incidence of serum anti-DNA precipitins in patients with systemic lupus erythematosus by counterimmunoelectrophoresis.

The technique of counterimmunoelectrophoresis (CIE) has been adapted for detection of serum precipitins to calf thymus (CT) DNA in patients with SLE, discoid LE, miscellaneous connective tissue and infectious diseases, and control populations. Of seventy-eight LE patients, 58% demonstrated anti-ss DNA precipitins, and 20% exhibited anti-ds DNA precipitins. Good correlation was noted between the presence of ss DNA precipitins and ss DNA binding values determined by the more sensitive ammonium sulphate precipitation assay. Depressed total serum haemolytic complement activity in CH50 mu/ml was noted in 64% of sera exhibiting ss DNA precipitins and 38% of those with negative ss DNA precipitins. There was a strong association, however, between ds DNA precipitins and depressed serum complement levels. Although less sensitive than primary binding assays, CIE can be used as a rapid and simple screening test for detection of circulating anti-native and denatured CT DNA precipitins. CT DNA serum precipitins are present in a significantly higher percentage of SLE patients when compared with other disease states and normal control populations.

Ammonium Sulfate↗
PubMed1989

Steep gradients of inert substances as supports for precipitin reactions.

Precipitin reactions were conducted in the wells of micro titer plates and the light "absorbance" at 405nm plotted as a function of the neg log2 dilutions of the antigens using the Titertek Multiscan apparatus. The procedure followed was to incorporate antibody in 20% sucrose and to diffuse the mixture into serial two-fold dilutions of antigen overlaid on the sugar-antibody columns in the wells. Where the antigen met its antibody in equivalence precipitin bands formed. The bands of precipitates remained suspended. The precipitates formed by mixing the antibody sugar mixture with the serial two-fold dilutions of the antigen were also recorded in the Titertek Multiscan apparatus. Tobacco mosaic virus and its IgY type antibody produced simoidal precipitin curves with the layering as well as the mixing techniques. The haemocyanin of the whelk and its IgY antibody yielded a precipitin diagram with the layering technique which gave evidence to three antigens. The three antigens in the haemocyanin was confirmed by two dimentional Laurell-electrophoresis. Semi-purified human colostral dimeric IgA and its IgY antibody produced a precipitin diagram which showed evidence of four of five antigens. With the mixing technique a single precipitin maximum was obtained preceded by a prozone. Rabbit Ig and its IgY antibody gave a precipitin curve with two maxima. The precipitin curve obtained when the reagents were mixed had one peak preceded by a prozone.

Animals↗
PubMed1987

Serum precipitins against microbes in mouldy hay with respect to the geographical location of the farm and to the work of farmers.

This study was based on a sample of 3,065 farmers from a larger survey population of 12,056 Finnish farmers. Data were gathered in a postal survey conducted by the Social Insurance Institution of Finland. Serum precipitins were determined by a microplate method of immune diffusion. The antigen panel consisted of mycelial antigens of Micropolyspora faeni, Thermoactinomyces vulgaris, Aspergillus fumigatus, and Aspergillus umbrosus. Geographical variation in the prevalence of precipitins was statistically significant, evidently due to climatic differences. The more intensive the cattle raising, the more commonly were precipitins found in the sera of farmers. For participation in animal tending (cattle, pigs, or poultry) or in plant cultivation work only, the prevalence of precipitins was largest among farmers who tended cattle or swine. According to earlier studies, serum precipitins to Thermoactinomyces vulgaris are associated with farmer's lung. Precipitins to this microbe were most commonly found in farmers who tended pigs and were also very common in farmers who worked only in plant cultivation. These findings imply that farmer's lung may also develop among pig farmers and grain producers. Precipitins to Thermoactinomyces vulgaris were clearly related to the type of grain drier used on the farm. The study failed to identify detailed tasks in farming associated with large prevalence of precipitins, probably owing to considerable overlap in the exposure encountered in different tasks.

Agriculture↗
PubMed1973

California arbovirus (La Crosse) infections. II. Precipitin antibody tests for the diagnosis of California encephalitis.

Precipitin antibodies to California group arboviruses were studied by double agar gel immunodiffusion (ID) and counterimmunoelectrophoresis (CEP). Forty children with California encephalitis (CE), 12 patients with other forms of meningoencephalitis, and 120 residents of endemic CE areas were tested. Precipitin antibodies were detected only in the 40 patients with CE, whereas hemagglutination-inhibiting, neutralizing, and complement-fixing antibodies were also found in persons without a history of CE. Precipitin antibodies did not persist for more than a year, in contrast to the other three antibodies which may be detected for 2 or more years. Of the children with CE, 36% had precipitin antibodies in their acute sera by CEP and 44% by ID. Precipitin responses were subtype-specific, and the patients reacted most strongly with La Crosse virus. The results indicated that precipitin techniques would be useful for the early detection of CE in some patients and that the presence of precipitin antibodies in a patient with acute central nervous system infection is strongly suggestive of CE. In addition, precipitin tests can be used to distinguish the California subtype responsible for CE in a given area.

Antibodies, Viral↗
PubMed1987

Precipitins against microbes in mouldy hay in the sera of farmers with farmer's lung or chronic bronchitis and of healthy farmers.

The aim of this study was to determine which precipitins against four antigens in 2,440 farmers are associated with the occurrence of farmer's lung (FL). The antigen panel consisted of mycelial antigens of Micropolyspora faeni, Thermoactinomyces vulgaris, Aspergillus fumigatus and Aspergillus umbrosus. As reference groups we used healthy farmers and those with chronic bronchitis. For the occurrence of precipitins against the four antigens there was a statistically significant difference between farmers with FL and healthy farmers but not between farmers with chronic bronchitis and healthy farmers. In a stepwise logistic linear regression analysis, farmers with FL and chronic bronchitis were compared to healthy farmers with respect to precipitins to the four antigens. Precipitins against Thermoactinomyces vulgaris differentiated farmers with FL (p less than 0.05) but not farmers with chronic bronchitis from healthy farmers. In Finland the occurrence of FL seems to be associated mainly with precipitins against Thermoactinomyces vulgaris, not with precipitins against Micropolyspora faeni as in Great Britain, and not with precipitins of Aspergillus umbrosus, which occurred most frequently in the sera of Finnish farmers. This association is in accordance with the exposure to spores of airborne moulds in farmers' work environment, where spore concentrations of Thermoactinomyces vulgaris have been measured to be about six times higher than those of Micropolyspora faeni.

Antibodies, Bacterial↗
PubMed1985

Factors influencing the development of serum precipitins to farmer's lung antigen in Quebec dairy farmers.

A total of 888 randomly selected dairy farmers participated in an epidemiological study to evaluate the prevalence of precipitins to farmer's lung antigens, and the socioeconomic factors associated with their presence. Precipitins were present in 75 farmers (8.4%) (65 to Micropolyspora faeni, seven to Aspergillus spp, two to both Aspergillus and Micropolyspora faeni, and one to Aspergillus and Thermoactinomyces vulgaris). The titres ranged from a dilution of 1/32 to a concentration of X 2 (Ouchterlony's double diffusion method). In the study population there were 544 who had never smoked, 146 ex-smokers, and 198 smokers. Sixty nine precipitin positive subjects were either never smokers or ex-smokers; only six were smokers. The negative relationship between cigarette smoking and precipitins was highly significant (p = 0.004). Factors positively associated with positive precipitin reactions were: size of farm, time spent in the barn, and the presence of a family member previously diagnosed as having farmer's lung disease. Interestingly, positive precipitin reactions were not associated with any of the following: use of silos, hay conditioners, or hay dryers; the presence or quantity of mouldy hay; or the presence of respiratory symptoms. It is concluded that precipitin analysis is not useful as a screening method for farmer's lung, though it can be of diagnostic value in acute farmer's lung disease.

Adult↗
PubMed1975

Incidence of serum precipitins against organic-dust antigens in different populations by counterimmunoelectrophoresis.

The incidence of serum antidust and antifungal precipitins was determined by counterimmunoelectrophoresis in 317 atopic and nonatopic subjects of three geographic areas (north central, southern, and western United States). The selected lyophilized crude antigens employed were from house dust, Micropolyspora faeni, Candida albicans, Alternaria tenuis, Aspergillus fumigatus, Puccinia coronata, Cantharellus cibarius, and Amborsia trifida. Antidust precipitins were detected with high frequency in atopic and nonatopic subjects of each geographic area (48 to 71 percent of different population subgroups). Precipitin reactions were generally intense and often multiple, in keeping with the marked heterogeneity of the crude dust antigen employed. Antidust precipitins were also present in serum fractions precipitated with ammonium sulfate and in IgG-rich fractions obtained by gel filtration (Sephadex G-200) and diethylaminoethyl-cellulose chromatography. Precipitins against crude somatic fungal and actinomycetic antigens were detected with considerably less frequency in all populations surveyed, considerably less frequency in all populations surveyed, and antiragweed precipitins were not detected. Our results suggest that prolonged environmental exposure to diverse, ubiquitous organic dusts results in a "normal" serum precipitating-antibody response. They also extend our previous finding of a high precipitin response against organic dusts in residents of the Gulf south area compared to other geographic areas.

Antibodies, Fungal↗
PubMed1987

Serum precipitins against microbes in mouldy hay with respect to age, sex, atopy, and smoking of farmers.

This study was based on a sample of 3,065 farmers from a larger survey population of 12,056 Finnish farmers. Data were collected in a postal survey conducted by the Social Insurance Institution of Finland. Serum samples for determination of precipitating antibodies were taken at local health centres. Precipitins were determined by the method of microplate immune diffusion. The antigen panel consisted of mycelial antigens of Micropolyspora faeni, Thermoactinomyces vulgaris, Aspergillus fumigatus, and Aspergillus umbrosus. Precipitins to any one of the four microbes were detected in 8.6% of the sera. The most common causes of positive precipitin tests were Aspergillus umbrosus and Thermoactinomyces vulgaris, which agrees with previous findings reported from Finland. In general, the precipitins were more prevalent among women, which corresponds to local cultural traditions, and in older farmers. The prevalence of precipitins did not differ between non-atopic and atopic (defined as past or present co-existence of atopic dermatitis including infantile eczema and/or hay fever or other allergic rhinitis) subjects. In contrast, the prevalence of precipitins was about 1.5-2 times larger among non-smokers than among smokers, which confirms the findings in previous reports. In future studies on occurrence of precipitins, the data should be controlled with respect to age, sex, and smoking.

Adult↗
PubMed1992

Restricted epitope recognition by precipitin-negative anti-La/SS-B-positive sera.

OBJECTIVE: To determine whether anti-La/SS-B-positive sera that are precipitin negative show a distinct B cell epitope pattern. METHODS: Serum reactivity was tested with recombinant La/SS-B fusion proteins. RESULTS: Among the 18 precipitin-negative anti-La/SS-B-positive sera, reactivity was confined to the full-length recombinant protein (La33.3) in 8 (44%); 5 of 18 (28%) reacted only with La33.3 and with the first 107 N-terminal amino acids (LaA), and 4 (22%) reacted with La33.3, LaA, and the middle region of the La molecule (LaC; amino acids 111-242). One serum reacted with La33.3 and LaC. None of the 18 precipitin-negative sera was positive on a carboxy-terminal fragment (LaL2/3; amino acids 346-408). In contrast, all 26 precipitin-positive anti-La/SS-B-positive sera reacted with La33.3, LaA, and LaC, and 92% reacted with LaL2/3. Rheumatoid factor and serum IgG levels were significantly lower in the precipitin-negative group, providing further evidence of a distinct serologic subset. CONCLUSION: The restricted epitope recognition by these sera may explain the lack of precipitin formation and may represent an early autoantibody response to La/SS-B.

Autoantibodies↗
PubMed1976

Alternaria IgG precipitins and adverse reactions.

Late reactions consisting of fever, malaise, and swelling at the site, 4 to 6 hr after injections of Alternaria extract occurred in several patients receiving immunotherapy with Alternaria. These patients had in common serum IgG precipitins and exquisite leukocyte histamine release sensitivity to Alternaria. Such precipitins were 3 times more frequent in patients receiving Alternaria immunotherapy than a control group of patients receiving immunotherapy with other antigens. A prospective study revealed that 5 of 23 Alternaria-sensitive persons had precipitins before immunotherapy and another 6 developed precipitins during therapy. Only one of the 23 experienced a late Alternaria reaction. Thus, precipitins to Alternaria are common and do not seem to be the basis for the late reactions we observed. The finding of precipitins does not contraindicate immunotherapy.

Alternaria↗
PubMed1968

Prevention of staphylococcal bacteriophage activity by antigen A precipitins in human sera.

Antigen A precipitins in human sera prevented plaque formation and propagation of staphylococcal bacteriophages. Over 20% of total IgG was removed from human sera by absorption with staphylococci containing antigen A. The specific precipitating antibody in rabbit antisera formed lines of idenity with antigen A precipitins in lower dilutions of human sera but formed lines of nonidenity with antigen A precipitins in higher dilutions of the same sera, suggesting both specific and nonspecific antigen A precipitins in human sera. The specific and nonspecific antigen A precipitins in human sera may prevent the in vivo activity of staphylococcal bacteriophages which have been demonstrated previously in animals whose sera do not contain either specific or nonspecific antigen A precipitins.

Antiviral Agents↗
PubMed1990

Precipitins in bird breeder's disease: how useful are they?

Precipitating antibodies to avian antigens play a controversial role in the diagnosis of bird breeder's disease (BBD). In order to establish the sensitivity, specificity and accuracy of precipitins in our laboratory, we conducted a prospective study including 128 sera received in 1988 for determination, by immunoelectrophoresis, of avian precipitins. Accurate information was obtained for 90 patients; definitive clinical diagnosis was given by the patient's own physician. We found a high sensitivity (86%), specificity (93%) and accuracy (92%) of avian precipitins in the diagnosis of BBD. Bayes' theorem was applied to determine the predictive value of the test with varying disease prevalence, and established that precipitins were particularly valuable for low or medium a priori probability. Using the receiver operating characteristic (ROC) curve we evaluated the effects of varying the positivity threshold of precipitins. The threshold used in this study appeared to offer the best compromise between sensitivity and specificity. These results suggest that the diagnostic value of avian precipitins in the work-up of BBD should be reconsidered, also because they represent a simple, cheap and non-invasive diagnostic test.

Adolescent↗
PubMed1988

Method for analysis of antigen-antibody precipitins in double immunodiffusion.

Ribonucleoprotein (RNP) antigen-antibody precipitin bands obtained by two-dimensional double immunodiffusion were systematically analyzed and compared using a microcomputer and a SPSS-PC statistical analysis package. Precipitins rated in respective agarose concentrations ranging from 0.3% to 1.5% were obtained from twofold dilutions of a calf thymus nuclear extract (CTNE) containing RNP antigen. These dilutions were reacted against the same dilutions of plasma containing anti-RNP antibody. A Mean Quality Index Score was calculated at each agarose concentration from the sum of ratings assigned for the intensity (thickness) of precipitin bands times the sum of ratings assigned for the clarity (clearness and sharpness) of the precipitin bands. This product was divided by the total number of possible precipitin reactions. The Mean Quality Index Score for the 0.4% agarose was significantly higher than the other concentrations (p less than or equal to 0.05). This method or similar approaches may allow a more systematic way of comparing precipitins developed in gel immunodiffusion.

Antigen-Antibody Reactions↗
PubMed1978

The absence of a relationship between serum precipitins and pulmonary disease in a community.

To study the role of serum precipitins in respiratory illness in a community, sera obtained from 3,047 residents of Tucson, Ariz., were tested for the presence of precipitating antibody to a battery of antigens. Positive reactions were obtained in 54 subjects (1.8 percent), a lower incidence than has been reported previously. The majority of these subjects were older than 54 years of age, an age distribution significantly older than the entire sample (P less than 0.01). Pulmonary function among the subjects with positive precipitin reactions was not significantly different from that of the asymptomatic nonsmokers of the entire sample. None of the subjects who were lifelong residents of Arizona had serum precipitins to any of the thermophilic actinomycetes antigens which were used in the testing. These antigens have been found in association with extrinsic allergic alveolitis, most frequently among patients living in the north central United States and were derived from strains of Micropolyspora faeni, Thermoactinomycetes candidus and vulgaris. Each subject with precipitins to one or more of the tested antigens was matched by age, sex, and socioeconomic class with two subjects from the sample who had negative precipitin reactions. The groups did not differ in their prevalence of respiratory symptoms or abnormalities of pulmonary function. We conclude that the presence of precipitating serum antibodies among subjects in a community is not indicative of the presence of immunologic pulmonary disease but merely reflects previous exposure to the tested antigen. In addition, individuals whose sera contain precipitating antibody appear to have no increased tendency to develop other types of pulmonary disease.

Adolescent↗