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PubMed2006

[Respiratory mechanics in patients with stage III pulmonary sarcoidosis and idiopathic fibrosing alveolitis: similarities and differences].

Impaired function of the lung was studied in 28 patients with Stage 111 pulmonary sarcoidosis and 17 patients with idiopathic fibrosing alveolitis (IFA). The study involved spirography, body plethysmography, and esophageal probing of respiratory mechanics. In patients with Stage III pulmonary sarcoidosis, the mechanics of respiration has the following similarities: restrictive ventilation disorder is revealed in IFA; the functional syndrome with a predominance of restriction is also detectable in some patients with Stage III sarcoidosis; significant differences are found in patients with IFA and Stage III pulmonary sarcoidosis: there is no marked impaired patency of peripheral bronchi in IFA; and all the functional changes found suggest that there is an increase in lung tissue rigidity and a decrease in the capacity of the lung to straighten; in Stage III sarcoidosis, of great importance is a marked impairment of patency of peripherally located bronchi, which is associated with the increase of this or that degree of lung compliance and in the retraction index.

Acute Disease↗
PubMed1990

Synthetic peptides containing T and B cell epitopes from human immunodeficiency virus envelope gp120 induce anti-HIV proliferative responses and high titers of neutralizing antibodies in rhesus monkeys.

We have previously described a synthetic peptide (T1-SP10) derived from two noncontiguous regions of HTLVIIIB envelope gp120 (T1, amino acids 428-443; SP10, amino acids 303-321) that induced type-specific anti-HIV neutralizing antibodies and T cell proliferative responses against native HIV gp120 when used as a carrier-free immunogen in goats. In this study, HTLVIIIB T1-SP10 synthetic peptides were used to immunize rhesus monkeys to determine if the peptides were capable of eliciting HIV-specific neutralizing antibody and proliferative responses in primates. Four compounds (alum, polyA:polyU, threonyl-muramyldipeptide (MDP) and IFA) were also compared for efficacy as adjuvants in this system. Rhesus monkeys immunized with T1-SP10 peptides generated high titers of antibodies against the immunogens and also against HTLVIIIB gp120. Sera from all four animals given T1-SP10 in IFA or threonyl-MDP neutralized infection by HTLVIIIB and blocked virus-dependent cell fusion events. A peak neutralization titer of 1:940 was seen in one animal given IFA (19600) and a titer of 1:900 was seen in one of the monkeys (17371) given threonyl-MDP. Proliferative responses of immune rhesus PBMC to T1-SP10 appeared after the first injection. After eight immunizations, two of eight monkeys (one injected with peptides in threonyl-MDP and one given peptides in IFA) had PBMC proliferative responses to native HTLVIIIB gp120. These data demonstrate that the carrier-free T1-SP10 synthetic peptide construct can induce high titers of neutralizing anti-HIV antibody responses and PBMC proliferative responses to HIV in primates.

Adjuvants, Immunologic↗
PubMed1991

[The immunological diagnosis of tuberculosis].

On the basis of literature review the article makes an appreciation of various methods for tuberculosis serological diagnostics. The authors mark a high information level of immunofermental analysis (IFA). 126 tuberculosis patients, 122 patients with non-tuberculosis etiology and 410 donors were examined with the aid of IFA (phosphide antigen). The min. diagnostic titer in pulmonary tuberculosis is 1:320, in nonpulmonary--1:160. The max. antigen titers in IFA (optical density unit of measurement) were in the cases of disseminated tuberculosis 1.32 0.12; the min.--in uterine tube tuberculosis--0.92 0.08. The titers of donors were 0.20 0.03, and of patients with non-tuberculosis diseases--0.25 0.04. IFA is recommended for practical application in tuberculosis and infectious clinics.

Antibodies, Bacterial↗
PubMed1991

Seroepidemiology of spotted fever group rickettsial infections in humans in Zimbabwe.

In sera collected throughout Zimbabwe the prevalence of antibodies reactive with Rickettsia conorii (Kenya) and a Zimbabwean spotted fever group rickettsia (ZSFR) was investigated using an indirect immunofluorescence assay (IFA). A random sample of these sera was also tested using a commercial IFA test. There was close agreement between IFA titres using the African rickettsial antigens and the commercial antigen slides. When differences in titre were detected, these were rarely greater than a twofold serum dilution. In Western blot immunoassays, IFA positive human sera detected immunogens of ZSFR and R. conorii (Kenya) that could also be demonstrated with homologous mouse antisera. The overall seroprevalence was 52% to R. conorii (Kenya) and 55% to ZSFR. For both antigens the highest seroprevalence was recorded from the south of the country, where the highest incidence of clinical tick-bite fever was reported in a questionnaire survey to medical practitioners. No difference was found between the seroprevalence in males and females, but high titres of antibody were common in samples from young people.

Adolescent↗
PubMedDate not supplied

Vaccination of turkeys with cell-free culture filtrate of Pasteurella multocida.

Turkeys given cell-free culture filtrate (CCF) of Pasteurella multocida strain R44/6 orally, via air sacs, or subcutaneously mixed 1:1 with incomplete Freund's adjuvant (IFA) at 6 and 9.5 weeks of age were compared with negative controls given bacteriologic medium and positive controls vaccinated with a commercial bacterin. At 13 weeks of age, serum antibody titers to P. multocida were detectable only in turkeys given CCF in IFA (low titers) and positive control turkeys (high titers), at which time turkeys were challenged orally with either the homologous strain or strain P-1059. Protection against challenge with strain R44/6 was provided by the commercial bacterin, CCF in IFA, and CCF given via air sacs. When turkeys were challenged with strain P-1059, protection was superior in turkeys given CCF via air sacs, intermediate in turkeys given commercial bacterin or CCF in IFA, and absent in negative control turkeys and turkeys given CCF orally. These results indicate CCF is an effective immunogen when administered via the lower respiratory tract for protecting turkeys against pasteurellosis.

Administration, Oral↗
PubMed1990

The Bascom Palmer Eye Institute Lyme/syphilis survey.

Serologic screening of patients for Lyme borreliosis began at the Bascom Palmer Eye Institute (BPEI) in September 1987. This report reviews the data on 641 sera from that date up to January 1, 1990. Initially only immunofluorescent (IFA) IgG and IgM titers were obtained. Because of increasing numbers of borderline and positive IFA tests, a Lyme enzyme linked immunosorbent assay (ELISA) was added in April 1988. Also, because of significant serologic cross reactivity in patients exposed to Treponema pallidum, rapid plasma reagin (RPR) and fluorescent treponemal antibody absorption (FTA-ABS) tests were added to the serologic screening panel. Of all sera tested, 10% showed reactive RPR tests and 22% showed reactive FTA-ABS tests. Lyme IFA IgG titers were greater than or equal to 1:64 in 17% of the sera, and Lyme ELISA tests were greater than 1.25 in 15% of the sera. Our experience agrees with reports that serum RPR or VDRL tests are nonreactive in Lyme borreliosis, and that false positive FTA-ABS tests can occur in Lyme borreliosis. The importance of getting all four tests--RPR, FTA-ABS, Lyme IFA IgG and IgM, and Lyme ELISA--in all patients suspected of spirochetal disease is emphasized.

Adolescent↗
PubMed1990

Sensitivity, specificity, and predictive values of ClinEase-Virastat saliva test for feline leukemia virus infection.

Detection of virus in saliva using a commercial enzyme-linked immunosorbent assay (ELISA), ClinEase-VirastatR, was compared to evidence of FeLV infection by the indirect immunofluorescent antibody assay (IFA) and plasma ELISA. The sensitivity and specificity of the saliva ELISA were derived by comparison to IFA and plasma ELISA in 103 cats from a large colony in New York State. The sensitivity of the saliva test in relation to IFA and plasma ELISA was approximately 100% and 93%, respectively. The specificity of the saliva ELISA in relation to IFA and plasma ELISA was approximately 85% and 92%, respectively. This test appears to be particularly suitable as a screening test for FeLV infection, especially in populations where the expected prevalence is low. Because of its high sensitivity, the saliva test has a high negative predictive value, particularly in populations where the disease is rare. Since the specificity is moderate, however, the predictive value of a positive test will be poorest in cats originating from places where the infection is rare (e.g. single cat households, or free roaming cats), and better among cats from environments having a high prevalence of FeLV (e.g. multiple-cat households).

Animals↗
PubMed1987

Hybridoma antibody characterization of stage-specific and stage-cross-reactive antigens of Eimeria tenella.

Hybridoma antibodies (HAb) have been raised against the sporozoite stage of 3 species of avian coccidia. These HAb were utilized in Western blot analysis, resulting in the immunoenzymatic detection of sporozoite and merozoite antigens of 1 species, Eimeria tenella. The 5 HAb specific for the sporozoite stage showed either single bands at 22 and 28 kDa or a large diffuse band in the 7-10-kDa range. The 4 HAb that cross-reacted with both asexual stages recognized either a single sporozoite or merozoite antigen of 90 kDa, or multiple antigens (47-69 kDa) for both stages. The 9 HAb demonstrated 5 different immunofluorescent antibody (IFA) patterns, and the 4 cross-reactive HAb showed similar IFA patterns with both asexual stages of E. tenella. The sporozoite-specific HAb which identified the 22, 7-10, and 7-8 kDa antigens showed surface, surface-internal, or internal IFA patterns. The other sporozoite-specific HAb, which labeled the 28-kDa antigen, stained the refractile body. The IFA of the 4 stage-cross-reactive HAb, which recognized the 45-60-kDa and the 90- or 47-69-kDa antigens, localized these antigens to the surface and tip, respectively. Rabbit anti-sporozoite serum appeared to recognize all of the sporozoite and merozoite antigens identified by the HAb as well as a variety of additional stage-cross-reactive antigens.

Animals↗
PubMedDate not supplied

[Use of formalinized epimastigotes for the detection of anti-Trypanosoma cruzi antibodies using immunoenzyme technics].

Formalin-fixed epimastigotes of T. cruzi were employed to develop an ELISA and a Dot-immunobinding assay (Dot-IA). The results were compared with those obtained by the indirect fluorescent antibody test (IFA). Fifty positive and twenty negative sera for Chagas disease, supplied by the reference center (Institute Mario Fatala Chaben, Buenos Aires, Argentina), were analyzed. When the quantitative indirect ELISA was performed, no overlapping between positive and negative sera was observed and the correlation with IFA was 100%. The sensibility of Dot-IA was greater than that of IFA with 2.5% of false positives. Dot-IA performed with epimastigotes is a simple and qualitative test which could be applied for screening of blood donors. On the other hand, the ELISA presented here is an objective test which does not require specialized equipment and could replace with advantage the IFA test for the serodiagnosis of Chagas' disease.

Animals↗
PubMed1986

Serum angiotensin-converting-enzyme in rabbits with and without pulmonary granulomatosis. Granulomatosis induced with complete-Freund's-adjuvant or BCG.

An animal model with pulmonary, non-caseating, granulomatosis was successfully reproduced in rabbits utilizing intravenous injections of complete-Freund's-adjuvant (CFA) or BCG. Granuloma formation from CFA injections was limited to the lungs, but BCG injections caused systemic granulomatosis (lung, liver and spleen) irrespective of whether the BCG was dissolved in saline or in incomplete-Freund's-adjuvant (IFA). Serum angiotensin-converting-enzyme (ACE) levels began to rise approximately 15 days following the intravenous injection of CFA, but similar rises following the injection of IFA without granuloma formation suggest that the ACE rise was not necessarily reflective of granuloma formation in rabbits. BCG in saline caused no rise in serum ACE, but when suspended in IFA the ACE rise was comparable to that resulting from IFA alone. However, the ACE level of broncho-alveolar-lavage cells obtained from rabbits 21 days post-injection of CFA was 7-fold higher than that of lavaged cells obtained 42 days post injection, correlating with an acute alveolitis occurring early during granuloma formation. These studies confirm the usefulness of intravenous injections of CFA or BCG for inducing a granulomatous state, but show that the assay of serum ACE is not useful for reflecting the granulomatous state in rabbits. In addition, serum ACE levels are 2-5 X higher in rabbits than in humans and tend to fluctuate spontaneously following delivery of the animals to the laboratory.

Animals↗
PubMed1987

Serological diagnostics of imported malaria in Czechoslovakia.

Two serologic techniques for malaria detection were compared in this study; the indirect fluorescent antibody (IFA) test used in 214 persons (38 Czechoslovak citizens returning from visits to tropical countries and 176 foreign visitors arriving to Czechoslovakia from areas endemic for malaria) and the indirect hemagglutination (IHA) test employed in 125 persons (29 Czechoslovak citizens and 96 foreigners). Comparisons revealed poor correlation between the IFA test and IHA test data. Of the two tests the IFA test appeared to be distinctly more reliable, more sensitive and more specific, the IHA test turned out to yield both false positive and false negative results. The antigen from Plasmodium gallinaceum gave lower IFA titres than P. falciparum antigen, but reacted with antibodies to all species of human plasmodia, and gave reliable test results. Positive serologic responses were appreciably more frequent in foreigners (46.0%) than Czechoslovak citizens (23.7%). The maximum percent positivity for malarial antibody was among individuals from tropical countries of Africa (74.6%), seropositivity in people from malaria endemic areas in Asia and Latin America was far less frequent (28.4% and 44.4%, respectively).

Animals↗
PubMed1988

Myocardial metabolism of radioiodinated methyl-branched fatty acids.

Methylated fatty acids labeled with radioactive iodine have been proposed as a means of studying regional myocardial uptake of fatty acids in man. To investigate the methylated fatty acid that is best adapted for an assessment of uptake, we have studied the influence of the number and the position of the methyl groups of IFA intracellular metabolism; 16-iodo-2-methyl-hexadecanoic (mono-alpha), 16-iodo-2,2-methyl hexadecanoic (di-alpha), 16-iodo-3-methyl-hexadecanoic (mono-beta), and 16-iodo-3,3-methyl-hexadecanoic (di-beta) acids were injected into the coronary arteries of isolated rat hearts. Intracellular analysis shows that the degradation of mono-alpha was always lower than that of IHA and the storage was always much higher. The differences between mono-beta and IHA were similar to those observed with mono-alpha, but were much more pronounced. With the two dimethylated IFAs there was an inhibition of both oxidation and esterification which led to an accumulation of free FAs in myocardial cells. In conclusion, mono-beta, di-alpha, and di-beta are potentially suitable for studying the cellular uptake of IFA since all of them, and particularly the dimethylated IFAs, have a low oxidation rate.

Animals↗
PubMed1987

An investigation into the clinical pathological changes and serological response in horses experimentally infected with Babesia equi and Babesia caballi.

Serologically negative horses, as determined with the indirect fluorescent antibody test (IFA), were infected with Babesia equi and 60 days later with Babesia caballi. The only clinical signs of disease observed in these animals were a febrile reaction and slight icterus. Haematological changes included a drop in haematocrit and haemoglobin concentration, as well as lowered platelet counts. The serum concentrations of albumin, iron and phosphorus were lowered. Mildly elevated serum bilirubin and fibrinogen concentrations were observed. Antibody titres were determined with the IFA and complement fixation (CF) tests. Antibodies to B. equi were first detected between Days 10-19 and 12-38 with the IFA and CF test, respectively, while the corresponding IFA periods for B. caballi were 6-8 days after infection. The parasitaemia of both B. equi and B. caballi infections never reached the 1% level.

Animals↗
PubMed1986

More experience on the microagglutination test in the diagnosis of Legionella pneumophila infection.

The sensitivity of the indirect immunofluorescence (IFA) test in Legionella pneumophila infection is said to be maximal when a plyimmunoglobulin conjugate is used. However commercially available non-class-specific fluorescent antisera are not always sensitive enough to detect IgM antibodies as class-specific conjugates do. IFA test's drawback is its inability to detect early stages of infection. We routinely performed the microagglutination (MA) test in order to check the reliability of this test alone in screening diagnostic work for L. pneumophila group 1 infections. The 252 sera tested were from suspected or confirmed legionellosis cases. Five-hundred and thirty sera from healthy-people, 49 sera from patients with serologically confirmed chlamydia, coxiella and mycoplasma pneumonia, and ten sera from patients with Pseudomonas aeruginosa infection were used as controls. There was a good agreement between IFA and MA tests, the MA proving almost as specific as, and in some cases more sensitive than the IFA test. This was particularly evident in early stages of infection. For these reasons, together with its low cost and the ease to perform, it appears that the MA test can be a useful screening test for presumptive cases of legionellosis even on a single serum specimen.

Agglutination Tests↗
PubMed1985

Serotyping of Haemophilus pleuropneumoniae by rapid slide agglutination and indirect fluorescent antibody tests in swine.

One hundred and forty-one isolates of Haemophilus pleuropneumoniae from Iowa and Illinois swine were characterized morphologically and biochemically and serotyped by rapid slide agglutination (RSA) and indirect fluorescent antibody (IFA) tests. Hyperimmune antisera were produced in rabbits using inactivated whole-cell suspensions of the reference strains for H pleuropneumoniae serotypes 1 to 7 and strain 202, representing the taxon "minor group." Cross testing of the reference strains and reference antisera indicated the antisera to be essentially serotype-specific, although reactivity of some antisera with heterologous strains was observed. Cultures of the 141 isolates formed adherent or smooth colonies or mixtures of these colony forms. Adherent and smooth colony types were found in all serotypes identified. Microscopic and biochemical characteristics of all isolates were typical of those previously described for H pleuropneumoniae. The overall incidence of H pleuropneumoniae serotypes was serotype 5, 55.3%; serotype 1, 34.0%; serotype 7, 7.8%; and nontypeable, 2.8%. Comparing the 2 test procedures, 87.2% of the isolates could be typed by RSA, and 66.0% could be typed by IFA. Cross-reactions between serotype 4 antisera and serotype 5 and 7 isolates were common with the IFA test. The reactions with serotype 7, but not serotype 5, were eliminated by cross adsorption of serotype 4 antisera. There was good correlation between the 2 test procedures, but RSA was judged to be more specific and sensitive than IFA.

Agglutination Tests↗
PubMed1985

Sensitivity and specificity of the indirect-fluorescent antibody test and two enzyme-linked immunosorbent assays in canine dirofilariasis.

Ninety dogs naturally infected with Dirofilaria immitis and 103 noninfected dogs, as determined by necropsy, were used to compare the sensitivity and specificity of the cuticular and somatic reactions of the indirect fluorescent antibody test (IFA-C and IFA-S, respectively) and 2 enzyme-linked immunosorbent assays (ELISA). In microfilaremic and amicrofilaremic heartworm-infected dogs, negative results were common for all serotests. In dogs without adult heartworms at necropsy, 32% to 49% were positive, using 1 ELISA, 27% to 29% were positive with the other ELISA, 15% to 36% were positive with the IFA-S, and 0% to 1% were positive using the IFA-C, depending on the classification of borderline reactions. The prevalence of false positive serotests was probably not due to the detection of precardial stages of D immitis in dogs obtained from areas of low endemicity. Until the causes of the false-positive tests are resolved, the use of currently available serotests for routine diagnostic screening or as criteria for instituting treatment is not recommended.

Animals↗
PubMed1974

Specificity of the indirect haemagglutination test with Plasmodium falciparum test cells. Comparison of indirect haemagglutination and fluorescent antibody tests on African sera.

The specificity of the indirect haemagglutination (IHA) test with Plasmodium falciparum placental antigen-sensitized test cells was examined with sera from healthy blood donors and from patients with diseases other than malaria. Only 1 nonspecific antibody reaction was seen in more than 700 tests. A comparison of IHA titres and indirect fluorescent antibody (IFA) titres with IgG and IgM conjugates on 503 sera from inhabitants of Mto Wa Mbu in Tanzania showed in successive age groups an increasing number of seropositive reactors with both tests. The increase in the proportion of positive reactions and in the mean titre levels started earlier but was more gradual in the IFA test than in the IHA test. Parasite carriers had higher antibody levels than people without an apparent parasitaemia. Parasite carriers in the younger age groups especially were more frequently seronegative in the IHA test than in the IFA test with anti-IgG conjugates. The reactivity of the IHA test with P. falciparum (Palo Alto/Aotus) antigen was higher than that with P. falciparum placental antigen and was thus closer to that of the IFA test with IgG conjugates.

Adolescent↗
PubMed1974

Development and decline of antiplasmodial indirect fluorescent antibodies in mice infected with Plasmodium berghei (NK65) and treated with drugs.

Malaria parasites in mice present a simplified rodent model for the immunological study of malaria. Experiments have been performed to determine the pattern and persistence of malaria antibody as detected by the indirect fluorescent antibody (IFA) test utilizing specific antimouse IgM and IgG conjugates. The antibody levels in mice inoculated with Plasmodium berghei and treated with antimalarial drugs were traced after complete elimination of the parasites from the host. Within 1-2 weeks after inoculation, both specific IgM and IgG reached peak levels, which thereafter declined rapidly. The results suggest that a high IFA titre may be taken as an indication of recent parasitaemia when the parasites are absent from the host. The protective role of the specific immunoglobulin was not found in the cured animals at the time when the animals showed a high IFA titer. It seems that the detected IFA may not reflect protective immunity against reinfection with malaria parasites.

Animals↗