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PubMed1987

Clinical and serologic studies of canine borreliosis.

During 1984 and 1985, blood samples were obtained from 271 dogs that were suspected of having borreliosis. The dogs lived in areas known to be infested with ticks and had been examined because of limb/joint disorders or for unknown illnesses marked by fever, anorexia, or fatigue. Lameness had been the most frequently reported clinical manifestation. Analyses of serum specimens, by an indirect fluorescent antibody (IFA) method or by an ELISA, detected antibodies to Borrelia burgdorferi, the etiologic agent of borreliosis in dogs and of Lyme disease in human beings. Antibody to B burgdorferi was detected in 76.3% of 114 specimens from dogs living in the lower Hudson Valley region of New York State (predominantly Westchester County), in 66.5% of 155 specimens from dogs from southern Connecticut, and in single specimens from dogs from Rhode Island and California. Geometric mean antibody titers peaked during the winter. Results of IFA tests and ELISA were in agreement, but the latter method yielded less variable results, had greater sensitivity, and was more easily standardized. Five dogs from New York State and Connecticut seropositive to B burgdorferi had developed kidney disorders during or after episodes of intermittent lameness. Application of murine monoclonal antibody in an IFA procedure verified the presence of B burgdorferi in renal cortical tissues from one dog.

Animals↗
PubMedDate not supplied

New prospects in immunology of toxoplasmosis: skin-tests for control of immunity and immuno-assays and agglutination tests for the detection of specific IgM antibodies.

An excretory-secretory (ES) antigen was extracted from supernatants of cell cultures infected with Toxoplasma gondii, purified and controlled according to current standards. In 638 volunteers, the correlation with fluorescent antibody was 94.2% and no false positive skin tests were noted. The skin test did not transform an originally negative serological test into a positive one. For the prevention of congenital toxoplasmosis, this sensitive, specific and inexpensive skin test can be widely used for the detection of immunity to Toxoplasma in women before their first pregnancy. During pregnancy, the detection of specific IgM is very important for the diagnosis of a recently acquired toxoplasmosis and allows for an immediate treatment. For this detection and for the diagnosis of congenital toxoplasmosis, five different serological tests were compared: Indirect Fluorescent Antibody-test (IFA), ELISA test, ELISA test After Capture of IgM (ACCAs), Reverse Enzyme Immuno Assay R-EIA), Double-Sandwich Enzyme Linked ImmunoSorbent Assay (DS-ELISA) and ImmunoSorbent AGglutination Assay (ISAGA). For 37 sera of recently acquired toxoplasmosis, IgM were detected in 98.7% with ISAGA, in 89.5% with DS-ELISA and ELISA in 83% with R-EIA and in 59% with IFA test. The best specificity is obtained with ISAGA, DS-ELISA and R-EIA, from controls with non immune patients (99 cases), patients with chronic toxoplasmosis (77 sera), rheumatoid factors (35 sera) or anti-nuclear antibodies (7 sera). In 21 sera from infants with congenital toxoplasmosis, ISAGA was positive in 13 cases (62%), IFA in 5 cases (24%), ELISA and R-EIA in 2 cases (9.5%) and DS-ELISA in 9 cases (43%).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1986

Characterization of the humoral immune response in Plasmodium falciparum malaria. III. Factors influencing the coexpression of antibody isotypes (IgM and IgG-1 to 4).

Isotypes (IgM and IgG-1 to 4) of anti-P. falciparum antibodies were investigated in sera of malarial patients or immune donors by enzyme linked immunosorbent assay (ELISA) and two indirect immunofluorescence assays (IFAs), one staining intra-erythrocytic parasites of all stages and the other a restricted number of parasite antigens deposited in the membrane of infected erythrocytes by invading merozoites (Perlmann & Wahlgren, 1983; Perlmann et al., 1984, Wahlgren et al., 1985a). There was no correlation in overall antibody titres between the two IFAs. Antibodies of both IgM and all four IgG isotypes were detected in both assays. With the IFA for intracellular parasites a brilliant fluorescence was obtained with antibodies of all isotypes. However IgG-2 antibodies often gave staining restricted to the surface of schizonts. The incidence and reactivity in individual sera of antibodies of the different isotypes did not relate to the immune status of the donors (acute infection or clinically immune) but related well to the degree of malarial exposure as reflected by the overall antibody titres. This, in all three assays, high titred sera frequently contained antibodies of all isotypes while low titred sera usually only contained antibodies of IgM, IgG-1 and IgG-3 isotype. On average, the overall expression of antibodies of different isotypes in individual sera appears to reflect a sequential downstream (5' to 3') activation of the corresponding Igh-C genes in P. falciparum specific B-cell clones.

Adolescent↗
PubMedDate not supplied

Development and use of hybridoma antibodies directed against Eimeria acervulina merozoites for cross-reactive and ferritin-labeling studies.

Hybridoma antibodies (Hab) were produced against Eimeria acervulina merozoites that had been separated from extraneous intestinal material by a fiber column technique before injection into mice. The Hab demonstrated three different immunofluorescent-antibody (IFA) patterns of tip, surface, or surface-internal fluorescence in or on the merozoites. Some Hab reacted with round immature schizonts, which were also present in the fiber-cleaned merozoite material. Variations in cross-reactivity were seen with a number of Hab tested by IFA with merozoites, sporozoites, and immature schizonts of different coccidial species. Certain Hab were species- and stage-specific, whereas others cross-reacted with some or all stages or species tested. One Hab apparently reacted with only a small percentage of the E. acervulina merozoites in the fiber-cleaned material. The ferritin (Fe)-labeling technique showed that with one Hab, which gave a surface-internal IFA pattern, there was an irregular clumping of the Fe label along the surface of the immature schizont. A heavier deposit of Fe label was seen on the area of the schizont where the merozoite was beginning to form. A heavy uniform labeling of Fe was seen on the surface of the pellicle of the mature merozoites. These results demonstrate that stage-specific and cross-reactive antigens are present in or on the merozoites of E. acervulina, and as shown with one Hab, surface antigens present on the immature schizont are incorporated onto the mature merozoite.

Animals↗
PubMed1986

Neutralizing antibody prevents type D retrovirus viremia in Celebes black macaques.

The Celebes black macaque (Macaca nigra) colony at the Oregon Regional Primate Research Center has a high incidence of simian acquired immunodeficiency syndrome (SAIDS-RF) that may be caused by type D retrovirus type 2 (SRV-2). During the spring and autumn screening of the colony, seven monkeys previously aviremic were found to be viremic on the basis of the Raji co-culture assay. These monkeys and control groups were selected for further study, which included titration of neutralizing antibody activity and immunofluorescent antibody (IFA) activity before and at the time that the animals became viremic. Results indicated that neutralizing antibody was not present before or at the time that monkeys became viremic and that control monkeys who were IFA+ and did not become viremic had high levels of neutralizing antibody. The IFA titre did not change significantly or predictably at the time the animals became viremic.

Acquired Immunodeficiency Syndrome↗
PubMed1979

Indirect fluorescent antibody test in occult dirofilariasis.

Indirect fluorescent antibody titers to Dirofilaria immitis microfilaria (IFA-mf) and peripheral eosinophilia were recorded from 15 to 52 months in ten experimentally infected dogs with occult dirofilariasis (heartworm infection without microfilaremia). Five dogs which were experimentally sensitized with D immitis microfilaria did not exhibit microfilaremia after inoculation with infective-stage larvae. In three other dogs, microfilaremia suddenly ceased after 4 to 7 months. In these three dogs, antimicrofilarial antibodies were detectable by IFA-mf test as soon as microfilaremia ended. In the remaining two dogs, which exhibited spontaneous occult dirofilariasis, antibodies were detected at the end of the prepatent period of 6 months. The presence of adult worms was confirmed by angiocardiography. Significant IFA=mf titers (greater than or equal to 1:8) persisted after successful treatment with an adulticide. Reinfection of treated dogs reestablished occult dirofilarasis. Eosinophilia was present in all dogs and peaked at about 3, 6, and 9 months after they were inoculated with infective-stage larvae. At necropsy, the ten dogs harbored gravid, reproducing adult worms in the heart and pulmonary arteries.

Animals↗
PubMed1985

Upper limit of normal titer for Legionella pneumophila group 1 by indirect immunofluorescence and microagglutination tests in healthy population in Italy.

The background prevalence of antibody to Legionella pneumophila group 1 in two groups of healthy population of the areas of Milano and Roma, Italy, was determined by testing single serum specimens from 530 blood donors by indirect immunofluorescence (IFA) test and by microagglutination (MA). The upper limit of normal (ULN) titer was found to be 16 by IFA and 8 by MA. There was little difference in the prevalence of titers in the two geographic regions. Of the 486 subjects from whom data were available titers above the ULN value did not vary significantly with age or sex. Considering the possibility of an equivocal area IFA titers greater than 64 and MA titers greater than 16 in single serum specimens can be considered as presumptive of infection.

Adolescent↗
PubMed1979

The prevalence of Encephalitozoon antibodies in dogs and an evaluation of the indirect fluorescent antibody test.

Fifteen dogs which were serologically negative to the IFA test against Encephalitozoon developed antibodies in their sera following experimental infection. Six other dogs which were not tested prior to infection had titres to Encephalitozoon after experimental infection. In a sequential study in four dogs, antibodies first appeared between 32 and 39 days after infection. These results show that the IFA test would be suitable for epidemiological studies. Fifty serum samples collected from two kennels in which encephalitozoonosis had been confirmed showed an IFA test positive prevalence rate of 70%. In 220 serum samples submitted for various clinial pathological examinations the prevalence rate of antibodies to Ebcephalitozoon was 18%.

Animals↗
PubMed1984

[Bronchiolar-alveolar cancer in idiopathic fibrosing alveolitis].

An observation of bronchiolo-alveolar carcinoma that developed in the presence of the idiopathic fibrosing alveolitis (IFA) in a woman of 57, is described. The duration of IFA was 12 years. Diffuse pneumosclerosis with the development of the so-called "honey-comb" lungs was observed. Numerous confluent foci of the bronchiolo-alveolar carcinoma in both the lungs are found in the presence of alterations typical for IFA (diffuse sclerosis of alveolar septa, microcystosis). The cause of death was progressing respiratory deficiency.

Adenocarcinoma, Bronchiolo-Alveolar↗
PubMed1983

Effect of pilus dose and type of Freund's adjuvant on the antibody and protective responses of vaccinated sheep to Bacteroides nodosus.

Groups of sheep were immunised twice with one or other of six vaccines consisting of purified pili from Bacteroides nodosus at three dose levels (10, 38 and 154 micrograms) and emulsified with either complete (CFA) or incomplete Freund's adjuvant (IFA). Beginning one month after vaccination the sheep were homologously challenged on irrigated pasture, with naturally transmitted foot rot for a period of 26 weeks. Statistical analyses of the number of feet per sheep with severe foot rot demonstrated that there was a significant effect of vaccinal dose but neither an adjuvant effect nor an interaction between dose and adjuvant. Similar conclusions were reached when the titres of antipilus agglutinins in the serum were analysed. By both criteria the responses to doses of 154 and 38 micrograms of pili were significantly better than to 10 micrograms, but not significantly different from each other. The IFA vaccines caused less reaction at the sites of injection than the CFA vaccines and within the former the vaccines containing 10 and 38 micrograms pilus produced less reaction than those containing 154 micrograms. Hence a vaccine containing 38 micrograms of purified pili in IFA is nearly optimal for homologous protection against severe foot rot and is acceptable in terms of the reaction at the injection site.

Agglutination Tests↗
PubMed1981

Suppression of experimental allergic encephalomyelitis in guinea/pigs by liposome-associated human myelin basic protein.

Human myelin basic protein (MBP) was inserted into phosphatidyl-serine liposomes and Hartley guinea pigs were treated with 1 or 2 injections of MBP-liposomes mixture by the intracardial route before an encephalitogenic challenge with MBP in CFA. Other groups of guinea pigs were pretreated with equivalent amounts of MBP in saline or of MBP in IFA. Of 24 untreated animals, 22 developed EAE and died or had to be sacrificed within 15 days after challenge. Only 4 of 29 guinea pigs treated with either 75 microgram or 112 microgram MBP-liposomes developed clinical signs of the disease. In the group pretreated with MBP in saline, 11 of 15 animals died, whereas in the MBP-IFA group, only 4 out of 10 died. Histologic modifications were also decreased in the MBP-liposomes and MBP-IFA groups, but in many instances, clinical normal guinea pigs showed disseminated perivascular infiltrates in the brain and spinal cord. Delayed hypersensitivity reactions to MBP were positive in all but 1 animal tested. Early T-rosette levels followed essentially the clinical course of the disease: they were drastically decreased 7 days after challenge in the untreated and MBP-saline-treated groups, but remained essentially normal in the MBP-liposomes group throughout the experiment. Lymphocyte transformation tests carried out in parallel with soluble MBP and with MBP-liposomes indicated that animals in certain groups responded preferentially to 1 form or the other of the antigen. Compared with prevailing procedures, the single i.v. injection of a relatively small amount of liposome-associated MBP appears to represent a promising approach for the antigen-specific suppression of EAE.

Animals↗
PubMed1982

Autoimmune effector cells. III. Role of adjuvant and accessory cells in the in vitro induction of autoimmune encephalomyelitis.

The present investigation shows that autoreactive effector cells that transfer experimental allergic encephalomyelitis (EAE) can be activated from spleens and lymph nodes of Lewis rats given a single injection of 25 micrograms myelin basic protein (BP) in incomplete Freund's adjuvant (IFA), despite the fact that the cell donors do not develop EAE. Rather, these donor rats are unresponsive to EAE when given an encephalitogenic emulsion of BP in complete Freund's adjuvant (CFA). Lymphoid cells from rats given a single injection of BP-IFA were almost as effective as cells from BP-CFA-treated rats with respect to transferring EAE after in vitro activation with BP or concanavalin A (Con A). Irrespective of whether donors received BP in IFA or CFA, BP-cultured spleen and lymph node cells (SpC and LNC, respectively) transferred EAE, whereas Con A-cultured SpC but not LNC exhibited effector cell activity. Con A-cultured LNC were able to transfer EAE if the cultures were reconstituted with irradiated adherent phagocytic cells (which could be obtained from normal Lewis rat spleens) or with conditioned medium from these adherent SpC. These findings indicate that accessory cells are required for in vitro induction of this T cell-mediated autoimmune response.

Adjuvants, Immunologic↗
PubMed1984

Specificity of antigens from pathogenic Aspergillus species. I. Studies with ELISA and immunofluorescence.

Studies were made by enzyme linked immunosorbent assay (ELISA) and indirect fluorescent antibody (IFA) tests on the reactivities and specificities of 13 antigens prepared from four species of Aspergillus against antisera from immunized rabbits and 64 sera from patients with aspergillosis, other systemic mycoses and nocardiosis. Although reactions in both serological tests were invariably strongest with homologous antigen: antibody systems, antisera from rabbits immunized with A. fumigatus, Blastomyces dermatitidis, Candida albicans and Paracoccidioides brasiliensis reacted in the ELISA test with all of the Aspergillus antigens. In contrast, cross-reactivity was virtually non-existent with antiserum to Histoplasma capsulatum. Of five antigens prepared from A fumigatus tested by ELISA against human sera from patients with aspergillosis and other nocardial and systemic fungal infections, sensitivities varied from 81 to 100% for sera from 32 patients with aspergillosis, and specificities from 20 to 97% for sera from 30 patients with nocardiosis and other systemic mycoses. Purified A. fumigatus C antigen reacted weakly with sera from eight of these 30 patients, but the reactions were readily distinguishable from those obtained with sera from patients with aspergillosis. At optimal serum dilutions, cross-reactivities of A. fumigatus in the IFA studies were non-existent in the sera from 28 patients with candidosis, coccidioidomycosis, cryptococcosis, histoplasmosis, paracoccidioidomycosis and nocardiosis. Sensitivities of IFA were 94% for patients with aspergilloma and 83% for patients with allergic bronchopulmonary aspergillosis.

Animals↗
PubMed1984

Accelerated expansion of antibody heterogeneity by complete Freund's adjuvant during the response to bacterial alpha-amylase.

Changes in the isoelectric focusing (IEF) spectra of specific antibodies were followed during the response of individual mice to bacterial alpha-amylase (B alpha A) in either incomplete or complete Freund's adjuvant (IFA or CFA). The response to a suboptimal dose of B alpha A was maximally enhanced by employing CFA at an optimal dose of Mycobacterium tuberculosis. Regardless of the strain difference in responsiveness to B alpha A between C3H/He (C3) and C57B1/6 (B6) mice, the enhancing effect of CFA was characterized by an accelerated expansion of IEF spectra and by the intensified stain of focused antibody, compared with the response of mice immunized with the same antigen dose in IFA. The manner and the rate of heterogeneity expansion during the enhanced antibody response to a low dose in CFA were quite similar to the strictly restricted expansion of spectra during a response of a high dose of B alpha A in IFA, although each mouse showed an individual banding pattern with a different degree of heterogeneity, depending on the antibody titre. Thus, CFA accelerated the expansion of IEF spectra during the response to B alpha A without affecting the general manner of sequential expansion of anti-B alpha A antibody heterogeneity.

Animals↗
PubMed1983

The inhibitory effect of human immune sera upon the in vitro development of Plasmodium falciparum.

Sera from patients who had recovered from malaria were examined for their capacity to inhibit the growth of Plasmodium falciparum in vitro. The sera were dialysed to eliminate any residual drugs taken by the donor. IgG purified from inhibitory sera was found to be as effective as the original sera. The inhibitory activity of some of the immune serum was pronounced after the second day in culture. This may suggest that the mechanism of action of antibodies affects the merozoites which appear for a short period in the two day cycle of the parasite. There was no correlation between antibody titre measured by IFA and the inhibitory capacity of the sera: some samples with high IFA titres did not inhibit the growth while some with low IFA titres inhibited the parasite. Autoantibodies directed against the erythrocytes, which were found in some sera, had no antimalarial inhibitory role and the absorption of them did not alter the inhibitory effect. There were more inhibitory sera among Nigerian than amount Thai and Ethiopian sera. The experiments were performed with a Nigerian strain and therefore the results may be explained by differences between the various falciparum strains of malaria.

Antibodies↗
PubMed1984

Application of electroimmunodiffusion and crossed electroimmunodiffusion tests for the diagnosis of visceral leishmaniasis (kala-azar).

Techniques of electroimmunodiffusion (EID) and crossed electroimmunodiffusion (CEID) were applied and compared with the indirect fluorescent antibody (IFA) test for the diagnosis of visceral leishmaniasis. Results obtained by EID on 28 serum samples of proven cases of kala-azar correlated well with IFA. False-positive reactions were encountered by IFA assay among healthy controls and non-kala-azar patients. Using EID technique, species-specific antibody to L. donovani was demonstrated in all sera of kala-azar patients. CEID was less sensitive than EID as a few false-negative results were obtained with this technique. It is concluded that the EID test which is specific, sensitive and more economical could be applied for diagnosis of systemic leishmaniasis.

Antibodies↗
PubMed1983

Antigenicity of bovine parvovirus in fetal infections.

The humoral immune response of bovine fetuses to bovine parvovirus (BPV) infection during the 2nd and 3rd trimesters was studied by the single radial immunodiffusion, hemagglutination-inhibition (HI), indirect immunofluorescence (IFA), microneutralization (MN), plaque-neutralization, and double immunodiffusion (DID) tests. Serum samples collected from 23 BPV-inoculated and several control fetuses were tested. The immunoglobulin (Ig) M concentrations reached 355 mg/100 ml at 10 days after fetal inoculations were done and then decreased. The IgG concentration increased 10 days after inoculation and was maximal 142 days later. A correlation between Ig concentrations and antibodies reacting in the HI, IFA, MN, DID, and plaque-neutralization tests existed in all samples. Neutralizing and HI antibodies were detected 10 days after fetal inoculations. The highest MN titer of 4,096 was detected in a fetus 10 days after the inoculation done during the 3rd trimester. Six serum samples were positive in the IFA test. These samples, collected 10 to 60 days after fetuses were inoculated, had IgG concentrations of 615 mg/100 ml or higher, and had titers of 16 to 64. Treatment of BPV with carbonate-bicarbonate buffer (pH 10.5) disrupted the virus and liberated antigens reacting in the DID test. Electron microscopic examination of the negatively stained antigen preparation revealed loss of structural integrity of the viral particles. This suspension of disrupted BPV was reactive with some of the fetal serum samples in the DID test, inducing 1 or 2 precipitin lines.

Animals↗