Serology of coccidioidomycosis

Summary We believe there is strong evidence to support a continuing search for coccidioidomycosis in new areas, in the Old World as well as in the New World, and in places with a climate and ecology different from the semi-arid conditions of the known endemic areas. Such an investigation would be justified in any population group where there is a high incidence of respiratory disease of unknown etiology. Very satisfactory and practical immunological techniques are available, but the present evidence indicates that the antigens used in these tests should be prepared from strains ofC. immitis recovered from the area to be investigated. Obviously this cannot be done at present, so such a program should be preceeded by an extensive survey of soil samples in the area in order to recover any existing native strains ofC. immitis. Whereas this would be the ideal situation, one could consider initiating the proposed study with coccidioidins prepared from selected strains of this fungus, incorporating as complete a spectrum of known antigens as is possible with our present knowledge, and keeping in mind that even this may not be adequate. We would welcome the opportunity to assist any investigator preparing to undertake a survey for coccidioidomycosis in his country.Paper read at the Eighth International Congresses for Tropical Medicine and Malaria, September 1968, Teheran (Iran).     

Serology of paracoccidioidomycosis

This review provides the background for understanding the role of a battery of diagnostic methods in paracoccidioidomycosis (PCM). This systemic mycosis is a disease endemic in many regions of Latin America, with sporadic cases also occurring throughout the world (mycosis of importation). Although excellent laboratory methods for diagnosis are available, there are deficiencies that must be met by continued research. Understanding the uses and limitations of a battery of laboratory methods is essential to diagnose PCM. Clinicians and laboratory directors must be familiar with the uses and limitations of a battery of serologic and mycological tests to accurately diagnose of PCM. Antibody and antigen detections are valuable adjuncts to histopathology and culture. More recently, the gp43 and gp70 antigen detection assay have improved the methodology of diagnosis of this mycosis, which improves reproducibility and facilitates monitoring antigen clearance during antifungal treatment. Furthermore, detection of antigen in cerebrospinal fluid and in bronchoalveolar lavage fluid increases the sensitivity for diagnosis of PCM in central nervous system and in pulmonary infections, respectively.     

Serology of paracoccidioidomycosis

The purposes of the present work were: i) to study the positivity indices and compare titers obtained with the indirect immunofluorescence (II), tube precipitation (TP), complement fixation (CF) and double immunodiffusion on agar gel (ID) tests in the sera of 196 patients with paracoccidioidomycosis before treatment, and ii) to compare the initial titers of II with those obtained 1 year or more after treatment. II was the most sensitive serologic reaction (85.2%), and the positivity indices for CF, ID and TP were 67.7%, 66.0% and 50.0%, respectively. The sera tended to show parallel mean titers in II, CF and TP tests. One year after treatment there was a fall in titers of II in 66.2% of patients. The data, taken as a whole, demonstrate the usefulness of the indirect immunofluorescent test and the importance of using 2 or more serologic tests for the diagnosis and monitoring of patients with paracoccidioidomycosis.     

Serology of histoplasmosis

We admit that the complete understanding of the serology of histoplasmosis has not as yet been realized. However, as laboratories continue to produce new and better techniques, not only for qualitative but also for quantitative assessment, we may be able to view a relatively complete picture in the near future.Paper read at the Eighth International Congresses for Tropical Medicine and Malaria, September 1968, Teheran (Iran).     

Serology of H-Y antigen

Summary Anti-H-Y antiserum is generally obtained from female inbred mice or rats that have been hyperimmunized with syngeneic male cells. The specificity of such antiserum is defined by its reactivity for male but not female cells. A number of conventional serological assays have been used to measure that reactivity. However, H-Y is a weak antigen, evidently represented sparingly on the surfaces of cells other than sperm, epidermal cells and brain cells; thus the srological assays for H-Y are technically difficult. Yet H-Y serology has enabled significant progress toward the understanding of primary sex differentiation.A recent advance in H-Y serology is the establishment of monoclonal anti-H-Y antisera which promise to facilitate analysis and clarification of the H-Y system.     

Serology of Aspergillus granuloma

A total of 21 cases of granuloma caused by Aspergillus species were encountered during the period 1972–79. The organs involved were nasal and paranasal sinuses, brain, orbit, subcutaneous tissue of cheek, lungs and endocardial valve in the decreasing order of their frequency. Aspergillus flavus was the main etiological agent. Immunodiffusion tests with various Aspergillus species as antigen showed a positivity of 17 out of 18 (94.4 per cent) cases. The role of precipitins in diagnosis and prognosis of the disease has been discussed.     

The Future of Fungal Serology

The incidence of invasive fungal infections continues to grow. Early and rapid diagnosis is essential to prevent morbidity and mortality. The number of assays available for the detection of fungal antigens in human body fluids are increasing in number and becoming part of the basic diagnostic workup for many fungal infections. Detection of specific antibody has been an important component in the diagnosis of fungal infections. Complement fixation and immunodiffusion continue to be the gold standard for antibody detection but are complex to perform, require extensive expertise, and are mostly performed in reference labs. Newer assays are being developed to reduce turn-around time, but have not been fully evaluated. A challenge for improving serologic assays is to move from crude antigens and polyclonal antibodies to purified and/or recombinant antigens and monoclonal antibodies, while retaining good sensitivity and specificity. Recent developments using lateral flow methodology have provided novel point-of-care antigen assays requiring little technical expertise. Such innovative techniques will help to keep the future of fungal serology bright.     

Serology and yeast classification

When analysed by an immuno-fluorescent test method allSaccharomyces spp. examined were antigenically distinguishable, with no natural grouping of yeast strains. The sero-types exhibited a continuous spectrum of antigen combinations. Extensive cellular variation was detected in serological response, which principally resulted from physiological differences between individual yeast cells but mutation was a minor contributor. Combination of divisiveness of the current serological analysis and the presence of transient physiologically-based “antigenic variants” rendered serology of dubious significance for yeast taxonomy. The role of yeast serology is assured, however, in relation to rapid test procedures for yeast identification. The author wishes to thank the Directors of Bass Production Ltd., for permission to publish this Paper. Generous donations of rabbit antisera from Dr. I. Campbell, Heriot-Watt University, are gratefully acknowledged.