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PubMed1962

Studies on Coccidioides immitis. I. A simple medium for in vitro spherulation.

Northey, W. T. (Arizona State University, Tempe) and L. D. Brooks. Studies on Coccidioides immitis. I. A simple medium for in vitro spherulation. J. Bacteriol. 84:742-746. 1962.-A simple medium is suggested which markedly enhances the in vitro conversion of the dimorphic fungus Coccidioides immitis. The principal component of this medium is Edamine, an enzymatic digest of lactalbumin. The arthrospore-spherule conversion was accomplished in as little as 12 hr when this medium was used. Maturation of the spherules with subsequent release of endospores was completed within 72 hr. The value of various supplements to the basal Edamine medium was investigated.

Albumins↗
PubMed1963

Studies on coccidioides immitis. II. Physiological studies on in vitro spherulation.

Brooks, Lula D. (Arizona State University, Tempe) and William T. Northey. Studies on Coccidioides immitis. II. Physiological studies on in vitro spherulation. J. Bacteriol. 85:12-15. 1963.-Studies on the amino acids assayed in Edamine revealed that the amino acids phenylalanine, tyrosine, and tryptophan, in addition to the amino acid derivatives dihydroxyphenylalanine (DOPA), epinephrine, tyramine monohydrochloride (tyramine HCl), and pyrocatechol play an important role in the Coccidioides immitis conversion process. In the presence of phenylalanine, tyrosine, tryptophan, DOPA, pyrocatechol, dextrose, and biotin, conversion as well as maturation was demonstrated. However, in epinephrine and tyramine HCl combinations, conversion occurred without maturation of the spherules. The availability of increased amounts of melanin precursors is suggested as a possible explanation for the increased susceptibility of the dark-skinned races to disseminated coccidioidomycosis. Conversion and maturation were also noted when lactic and fumaric acids served as carbon sources. The conversion of a limited number of arthrospores to spherules and their subsequent maturation in the presence of only phenol and biotin suggest the possibility that the key to the C. immitis conversion process lies in the availability of certain ring structures.

Biotin↗
PubMed1964

CONTINUOUS IN VITRO CULTIVATION OF SPHERULES OF COCCIDIOIDES IMMITIS.

Breslau, Abraham M. (Veterans Administration Center and University of California Los Angeles Center for the Health Sciences, Los Angeles, Calif.), and Mike Y. Kubota. Continuous in vitro cultivation of spherules of Coccidioides immitis. J. Bacteriol. 87:468-472. 1964.-Spherules of Coccidioides immitis were grown in vitro in continuous culture for more than 4 years. Cultures were grown in modified Converse medium in a modified Lubarsky and Plunkett culture tube incubated at 40 C under increased CO(2) tension. Spherules that had transformed from hyphae were freed from mycelial fragments, and were allowed to settle to the bottom of the tube. The mycelium which normally degenerated at 40 C was removed repeatedly with a syringe and needle until the culture was almost pure spherules. For continuous culture, 10 to 12 ml of old medium were removed, and were replaced by fresh medium previously bubbled with a mixture of 20% carbon dioxide and 80% air.

Biotin↗
PubMed1964

SIGNIFICANCE OF SOIL SALINITY ON THE ECOLOGY OF COCCIDIOIDES IMMITIS.

Elconin, Ann F. (University of Southern California, Los Angeles), Roger O. Egeberg, and Margaret C. Egeberg. Significance of soil salinity on the ecology of Coccidioides immitis. J. Bacteriol. 87:500-503. 1964.-An 8-year study of the soil in a small parcel of land where coccidioidomycosis is endemic was conducted. Over 5,000 samples collected from the surface of the soil at monthly intervals were tested for the presence of Coccidioides immitis. These samples were also analyzed to determine their major chemical composition. During the first 3 years, C. immitis was recovered in profusion from the spring samples, but during the next 4 years the fungus virtually disappeared from this endemic area. C. immitis reappeared in the spring of the final year of this study. There had been no significant deviation in the climatic conditions, flora, or fauna of the region. Chemical analysis of soils showed a marked elevation of the soluble salts (principally Na, Ca, SO(4), and Cl) during those years when C. immitis was recovered. The soluble salts, expressed in terms of the saturation extract conductivity, ranged from 11 to 27 in those spring seasons when C. immitis was recovered, and from 3.5 to 8.8 when it was not found. This degree of correlation indicates that the high level of surface salinity encouraged the growth of C. immitis, and could be a factor in accounting for the spotty distribution of this fungus within endemic areas.

Calcium↗
PubMed1964

EFFECT OF SALINITY AND TEMPERATURE ON COCCIDIOIDES IMMITIS AND THREE ANTAGONISTIC SOIL SAPROPHYTES.

Egeberg, Roger O. (University of Southern California, Los Angeles), Ann F. Elconin, and Margaret C. Egeberg. Effect of salinity and temperature on Coccidioides immitis and three antagonistic soil saprophytes. J. Bacteriol. 88:473-476. 1964.-Experiments exploring the factors which determine the ability of Coccidioides immitis to survive and reproduce in the soil in situ are described and discussed. Previous work indicated that soil temperatures and salinity influence the growth and distribution of C. immitis. It was thought that these factors might work through enhancing the growth of C. immitis or inhibiting the growth of its possible antagonists, or both. In searching for antagonists, samples of surface soil from an endemic area were screened by standard culture techniques. Three significant antagonists were isolated and were identified as two strains of Bacillus subtilis, and Penicillium janthinellum. Subcultures of each of these isolates were grown on Saboraud's media modified by sodium chloride and calcium chloride in parallel series. The salts used were the predominant salts, and the range of temperature was comparable to that found in the soil. The organisms were grown at 18 to 27 C and at 40 C. The latter temperature approximated the temperature of the top centimeter of soil for 4 to 6 hr a day in the spring when C. immitis is recovered. P. janthinellum was unable to survive 40 C. The growth of the other two, while unaffected by temperature change alone, was inhibited by the salts. Conversely, C. immitis was stimulated by the salts when grown at the higher temperature. These findings support the hypothesis that markedly increased salinity and seasonal high temperature of the surface soil inhibit or kill these antogonists while enhancing the growth of C. immitis.

Bacillus subtilis↗
PubMed1998

Coccidioidal infection of the thyroid.

Infection of the thyroid gland with Coccidioides immitis, the causative agent of coccidioidomycosis, is very rarely recognized antemortem. We report 2 recent cases, one immunosuppressed by corticosteroid treatment of sarcoidosis and the other without any recognized impairment of host defenses. In the first case, thyroid gland involvement was but 1 indication of disseminated infection. In the second case, the patient appeared to have autoimmune thyrotoxicosis without clinical evidence of coccidioidomycosis elsewhere. Although historical autopsy studies have indicated that coccidioidal involvement of the thyroid gland can infrequently occur as part of fatal disseminated infection, to our knowledge only 2 other cases of infection detected during life have been reported. Optimal treatment of this rare complication of coccidioidomycosis is uncertain.

Abscess↗
PubMedDate not supplied

Pulmonary coccidioidal pseudomycetoma.

Coccidiomycosis is rarely associated with a pulmonary mycetoma. We report a patient with progressive cavitary coccidiomycosis, whose initial radiographic and clinical appearance simulated a mycetoma. Examination of the surgically resected lung showed necrotizing Coccidioides immitis granulomas with spherules and arthroconidialike structures, but no evidence of a mycetoma. We propose the term pulmonary coccidioidal pseudomycetoma as the best descriptor for this patient's clinical, radiographic, pathologic, and microbiologic presentation.

Adult↗
PubMed2005

Comparison of Coccidioides immitis serological antibody titres between forms of clinical coccidioidomycosis in horses.

A retrospective study was performed to determine if there is an association between serological Coccidioides immitis antibody titres (IgG) and form/severity of coccidioidal disease in horses, and to identify trends in survival and treatment success based on the form of the disease. Data were obtained on horses with positive serological titres tested at the Coccidioidomycosis Serology Laboratory, School of Medicine, University of California, Davis from 1981 to 2004. Thirty-nine cases in which a diagnosis of coccidioidomycosis had been made were selected for inclusion. Six distinct categories were identified including abortion (n=6), miliary/interstitial pneumonia (n=6), pneumonia with thoracic effusion (pleural or pericardial) (n=11), disseminated (n=10), osteomyelitis (n=3) and external abscessation (n=3) both without pulmonary disease. Statistical differences in titre distribution were found between the abortion category and the pulmonary category (P=0.003), the abortion category and pneumonia with thoracic effusion (P=0.001), the abortion category and disseminated disease (P=0.001), and the pulmonary form and pneumonia with effusion (P=0.001). The other categories had overlapping titre results. Higher serological antibody titres seemed to be associated with a poorer prognosis for survival. Categories with the highest titres, disseminated (geometric mean titre=104) and pneumonia with thoracic effusion (geometric mean titre=226), were overwhelmingly fatal (19/21 known deaths) due to severe clinical disease. The categories with lower titres, abortion (geometric mean titre=4), bone involvement only (geometric mean titre=13) and cutaneous (geometric mean titre=5), had a better survival rate (10/12 known survivors) and less severe clinical disease. Measurement of serological titre may be a useful diagnostic aid in establishing form and severity of disease and thus inform prognosis.

Animals↗
PubMed2005

Immune response of vaccinated and non-vaccinated mice to Coccidioides posadasii infection.

An immunogenic, recombinant protein of the fungal respiratory pathogen, Coccidioides posadasii, was previously identified as a beta-1,3-glucanosyltransferase homolog (Gel1) and shown to confer protection to C57BL/6 mice against coccidioidomycosis. However, little is known about the nature of the humoral and cellular immune responses of these vaccinated mice to intranasal infection with a lethal inoculum of C. posadasii spores compared to non-immune control animals. Our studies showed that protective immunity in mice vaccinated with two 1 microg doses of the recombinant Gel1 (rGel1) plus adjuvant was characterized by high titers of antigen-specific IgG2c and elevated levels of interleukin (IL)-12 and interferon-gamma (IFN-gamma) production at 7-14 days post-challenge compared to significantly lower levels of the respective antibody and cytokines in non-immune, infected mice. Mice immunized with either 0.2 or 5 microg doses of rGel1 plus adjuvant were less well protected and showed evidence of a marked decrease in the level of T helper-type 1 (T(H)1) immune response. Early T(H)1 immune regulation is essential for protection against pulmonary infection with Coccidioides, and the dose of the rGel1 vaccine narrowly defines the nature of immune response in the lungs of infected mice.

Animals↗
PubMed2002

Disease surveillance in recombining pathogens: multilocus genotypes identify sources of human Coccidioides infections.

Molecular surveillance of pathogenic microbes works by genotyping isolates with DNA fingerprinting techniques and then using these genotypes to assign individuals to populations. Clonality is assumed in many fingerprinting studies, although this assumption has been shown to be false for many organisms. To accommodate recombining organisms into surveillance programs, methods using population allele frequencies in combination with individual multilocus genotypes are necessary. Here, we develop a statistical method appropriate for haploid recombining microbes that allows individuals to be assigned to populations. We illustrate the usefulness of this technique by inferring the source populations for Coccidioides isolates recovered from patients treated outside the endemic area of Coccidioides sp., the etiological agents of human coccidioidomycosis, but with a travel history including visits to one or more endemic areas.

Alleles↗
PubMed2002

Molecular approaches to the study of Coccidioides immitis.

The study of the molecular biology of Coccidioides sp. is only just beginning. As the importance of coccidioidomycosis grows as a public health problem, our need for understanding of pathogenesis, immune responses, and improved antifungal therapy also increases in proportion. Tools have now become available to study gene manipulation in this pathogen and this will allow molecular approaches to be used. Genetic experiments will also be accelerated by the availability of the whole coccidioidal genome, expected to be made public in the spring of 2003 (see http://www.tigr.org/tdb/tgi/cigi/GenInfo.html). Thus, there seems to be several reasons to expect considerable progress in the coming years.

Animals↗
PubMed1986

Treatment of murine coccidioidal meningitis with fluconazole (UK 49,858).

Male ICR mice were challenged intracerebrally with endospores of Coccidioides immitis and then treated with water (control), fluconazole, amphotericin B (Fungizone), or ketoconazole (Nizoral). All three drugs markedly prolonged survival, and all three drugs lowered brain colony counts of C. immitis. Survival of mice treated orally with fluconazole at the high dose was longer than in the ketoconazole treated group. Amphotericin B was more efficacious than fluconazole. Further investigations are needed to determine the efficacy of fluconazole in treatment of coccidioidal meningitis.

Amphotericin B↗
PubMed1992

Coccidioides immitis presenting as a mycelial pathogen with empyema and hydropneumothorax.

A previously healthy Caucasian male developed hydropneumothorax and a pleural peel filled with pleomorphic, septate hyphae. The only organism grown from cultures of the lung and pleural fluid was Coccidioides immitis, confirmed by exoantigen testing. Spherule-endospore forms were produced, however, following injection of the arthroconidial tissue isolate into BALB/c mice. The patient had a positive immunodiffusion complement-fixation test and developed a positive coccidioidin skin test during therapy. He recovered following thoracotomy and wedge resection of the ruptured coccidioidal cavity, and therapy with amphotericin B followed by fluconazole. The sole presence of the mycelial form of the dimorphic fungus C. immitis in the pleural space may have been due to a low CO2 partial pressure at that site secondary to a bronchopleural fistula. The case shows a distinctive and uncommon presentation of coccidioidomycosis which demonstrates the specificity of both the immunodiffusion complement-fixation assay in diagnosing this disease and the exoantigen test in confirming culture results.

Animals↗
PubMed2004

Profiling gene expression in Coccidioides posadasii.

Coccidioides posadasii is a dimorphic fungal pathogen which grows as a filamentous saprobe in the soil and multicellular parasitic form in host lung tissue. Studies of gene expression profiles during saprobic and parasitic phase development can provide clues about morphogenetic regulation and may lead to the discovery of molecular targets for novel antifungal drugs. Suppression-subtractive hybridization (SSH) and quantitative real-time polymerase chain reaction (QRT-PCR) were used to identify and quantify differential gene expression during in vitro growth of Coccidioides. DNA fragments obtained from the subtraction of cDNA pools derived from the saprobic and parasitic phase RNA preparations were each cloned into an appropriate vector and subjected to sequence analysis. Semi-quantitative, reverse transcription polymerase chain reaction (RT-PCR) experiments were first conducted to assess whether these inserts represented differentially expressed genes. Nucleotide sequences of the partial and full-length genes selected by RT-PCR were obtained by genome walking and rapid amplification of cDNA ends (RACE) methods. QRT-PCR analysis of the expression of these genes during saprobic and parasitic cell growth was then conducted using DNA standard curves normalized to a constitutively expressed control gene. Four C. posadasii genes whose expression is essentially restricted to the parasitic cycle were discovered using this approach. These genes include homologues of OPS1 (encodes opsin-related protein), MDR1 (multidrug resistance protein), ALDR1 (aldehyde reductase), and PSP1 (hypothetical lipid transporter/flippase protein). The combined applications of SSH and QRT-PCR permit global analysis of gene expression patterns in C. posadasii.

Coccidioides↗
PubMed2000

Flow cytometric assessment of human peripheral blood mononuclear cells in response to a coccidioidal antigen.

The in vitro responses of peripheral blood mononuclear cells (PBMC) from healthy immune and non-immune donors were assessed by flow cytometry after incubation with the coccidioidal antigen toluene spherule lysate (TSL). After 120 h of incubation with 100 microg ml(-1) of TSL, expression of the activation markers CD69, CD25 and human leukocyte antigen-DR were all significantly increased in CD3+ lymphocytes from immune donors compared to non-immune donors (P < 0.03 for all). No differences in the surface expression of the costimulatory molecules CD28, CD152 or CD154 was seen between immune and non-immune donors after either 24 or 120 h of TSL incubation, nor were differences detected in the expression of the B7 ligands CD80 or CD86 on CD14+ monocytes. The percent of CD3+ lymphocytes expressing intracellular interferon-gamma (IFN-gamma) was significantly increased in immune compared to non-immune donors and was further increased by the addition of 10 ng ml(-1) of human recombinant interleukin (IL)-12 (P < 0.05 for both). Both CD4+ and CD8+ lymphocytes contributed to IFN-gamma production. These data indicate that coccidioidal antigen stimulation of lymphocytes from healthy immune donors leads to specific expression of activation molecules and production of intracellular IFN-gamma. Addition of IL-12 leads to a significant recruitment of cells producing IFN-gamma among immune donors.

Abatacept↗
PubMed1999

Proline-rich vaccine candidate antigen of Coccidioides immitis: conservation among isolates and differential expression with spherule maturation.

A proline rich antigen (PRA), which protects mice against Coccidioides immitis, has been analyzed for differential expression and variation among isolates. Northern blots of RNA from different stages of growth were probed with previously cloned cDNA and showed that mRNA for PRA increased as spherules transformed and matured from mycelia. This pattern corresponds to the relative potency of whole cell vaccines from similar preparations. The PRA gene was then cloned from a genomic library of the Silveira strain of C. immitis and its sequence analyzed. Eight other coccidioidal isolates, selected for diversity in geographic origin and resulting clinical disease, demonstrated heterogeneity in Southern blots and in sequences of polymerase chain reaction products. Silveira differed from other California isolates at 33 of 555 bases, whereas it differed from non-California isolates by <=2 bases. Only one of these substitutions affected protein sequence. Thus, tests or vaccines based on this gene are likely to cover most isolates.

Animals↗
PubMed2002

Levels of matrix metalloproteinase-9 within cerebrospinal fluid in a rabbit model of coccidioidal meningitis and vasculitis.

Matrix metalloproteinase (MMP)-9 is produced by the central nervous system and inflammatory cells in a variety of inflammatory conditions in both animals and humans. MMP-9 promotes inflammation, breakdown of the blood-brain barrier, and vasculitis. Because vasculitis is seen frequently in patients with coccidioidal meningitis (CM), this study evaluated the presence of MMP-9 within the cerebrospinal fluid (CSF) of rabbits infected intracisternally with Coccidioides immitis arthroconidia. Infected rabbits demonstrated systemic and neurological sequelae to infection, including CSF pleocytosis. Levels of MMP-9 within CSF were assayed by use of zymography and compared with MMP-2 levels, which served as an internal control. Elevated levels of MMP-9 were detectable by day 3, continued to increase through day 10, and declined by day 15 after infection. MMP-9 may contribute to inflammation and vasculitis in this animal model. Future work can focus on evaluation of MMP inhibitors, to gain a better perspective of the role of this MMP in CM.

Animals↗
PubMed2003

A murine model of coccidioidal meningitis.

Coccidioidal meningitis is lethal in humans. A reproducible murine model was established by lumbar intrathecal injection of Coccidioides immitis arthroconidia. Cerebrospinal fluid (CSF) samples were obtained by cisternal puncture. Lethal infection developed in all mice given 10-60 colony-forming units (cfu). Lethargy, ataxia, or paralysis preceded death. Temporal studies after challenge with 27 cfu revealed positive brain (4/5 mice) and spinal cord (2/5 mice) cultures on day 3; CSF samples contained 688 leukocytes/mm(3) and 33 cfu/mL. The results of histopathologic analysis were unremarkable. By day 8, all mice were culture positive (5.0 log(10) cfu in brain tissue and 4.1 log(10) cfu in spinal cord tissue); CSF samples contained 4833 leukocytes/mm(3) and 3425 cfu/mL. Histopathologic examinations showed acute meningitis of the brain and spinal cord, some parenchymal invasion and abscesses, and meningeal arteritis. Groups of mice given ketoconazole had prolonged survival and suppressed lung disease; histopathologic examination demonstrated granulomatous meningitis, possibly a more chronic form. With the development of these models, studies of pathogenesis, host response, and therapy are possible.

Animals↗