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At least 19 recordsLinked to original sources
PubMed1977

Histoplasma meningitis with common variable hypogammaglobulinemia.

Histoplasma meningitis (HM) has been reported to occur primarily in association with disseminated histoplasmosis (DH). We report a case of histoplasma meningitis occurring in a patient with common variable hypogammaglobulinemia (CVH) in which no manifestations of DH were observed. L. L., a 66-year-old Caucasian male, clerical worker, developed occasional episodes of dizziness and tinnitus in mid-1971. During 1972, increasing frequency of these episodes and gradually progressive confusion were noted. In January 1973, vomiting, forther confusion, obnubilation, and a left central facial paresis developed and he was hospitalized. Physical examination revealed no pulmonary abnormalities, lymphadenopathy or hepatosplenomegaly. Over the ensuing 6-week evaluation, there was occasional fever to 38.5 degrees C. Chest roentgenogram was normal. Cerebral angiography suggested a mass in the left cerebellar hemisphere. EEG was diffusely slow. Multiple CSF examinations revealed: Glucose 7-18 mg/with a normal blood glucose, protein 109-256 mg/and cells 66-140 (95 + % mononuclear). Histoplasma capsulatum was cultured from CSF but not from sputum, urine, blood or bone marrow. Skin tests for PPD, histoplasmosis, coccidiodomycosis, blastomycosis, mumps, dinitrochlorobenzene and streptokinase-streptodornase were negative then and 6 months later. Histoplasma serum antibody was absent. Immunoglobulin analysis revealed IgG 430 mg %, IgA 46 mg %, and IgM 35 mg %, which with the history and skin test results suggested CVH. Treatment with 2.51 gm of amphotericin B given intravenously over a 3-month period resulted in complete reversal of all neurologic signs and clearing of the confusion. The remission has been maintained for two years. This case represents a primary infection of the CNS by histoplasma. The relationship between the HM and the CVH will be discussed.

Agammaglobulinemia↗
PubMed1976

Specific immunological test for the rapid identification of members of the genus Histoplasma.

A sensitive and specific immunological method was developed for rapid identification of the mycelial forms of Histoplasma capsulatum var. capsulatum, H. capsulatum var. duboisii, and H. farciminosum and for separation of these pathogenic fungi from morphologically similar hyphomycetes and other fungal pathogens. This method is based on the fact that all of the Histoplasma spp. produce H and M histoplasmin antigens, whereas the other fungi do not. Inocula consisting of heavy mycelial growth from a pure, full-grown culture were transferred into flasks containing small volumes of brain heart infusion broth. These cultures were placed on a shaker and grown at 25 C. Using the micro-immunodiffusion technique and antisera containing antibodies to H and M precipitinogens, we detected exoantigens in 3-day-old brain heart infusion culture supernatants concentrated 25 and 50 times. The ability of the procedure to identify Histoplasma spp. was evaluated by testing 96 unknown mycelial cultures that grossly or microscopically resembled Histoplasma spp. Three- and six-day-old concentrated culture supernatants prepared from each unknown were tested against rabbit anti-Arthroderma tuberculatum, Chrysosporium keratinophilum, H. capsulatum var. duboisii, and Corynascus (Thielavia) sepedonium sera and human histoplasmosis case serum. Each unknown was also identified by conventional laboratory procedures involving cultural and, where necessary, in vivo studies. In the comparative evaluation the immunological test was observed to be 100% sensitive. It permitted the accurate generic identification of the Histoplasma spp. within 5 days, in contrast to the average of 33 days required by the routine mycological procedure.

Antigens, Fungal↗
PubMed1978

Histoplasma meningitis with hyperactive suppressor T cells in cerebrospinal fluid.

Histoplasma meningitis usually occurs in conjunction with disseminated histoplasmosis. We studied a patient with common variable hypogammaglobulinemia who manifested meningitis without disseminated histoplasmosis. No histoplasma antibody was detected in cerebrospinal fluid (CSF) or blood. Evaluation of lymphocyte function in the blood revealed normal numbers of T cells with increased numbers of B cells. Most blood lymphocytes were identifiable, but most lymphocytes in CSF were null cells. Lymphocyte proliferative response to phytohemagglutinin or pokeweed mitogen was poor. T cells in CSF suppressed proliferative responses to histoplasma antigen by cells from blood or CSF, whereas T cells from blood did not. This difference suggested compartmentalization of T-cell function. The lack of humoral and cellular response to histoplasma in CSF may have allowed meningitis to develop, while the cellular response to histoplasma elsewhere prevented development of disseminated histoplasmosis.

Aged↗
PubMed2025

Expansion of secreted cystine knot proteins reveals virulence factors in the human fungal pathogen Histoplasma.

Identifying fungal secreted factors that influence host infection remains a key challenge in microbial pathogenesis. While secreted effectors, particularly small cysteine-rich proteins, are well characterized in plant fungal pathogens, their counterparts in mammalian pathogens are understudied. We apply criteria from plant fungal effectors to the mammalian fungal pathogen Histoplasma, yielding a set of putative effectors highly enriched for knottins, proteins that adopt a distinctive cystine knot fold. Using an algorithm, we further identify 25 putative knottins in the Histoplasma genome, revealing a significant expansion of knottin genes. Knottin domains are found in diverse molecules but play an unknown role in virulence. Functional studies of individual Histoplasma knottins demonstrate their critical roles in intracellular survival and host cell lysis during macrophage infection as well as virulence in vivo. These findings highlight the importance of knottins in fungal pathogenesis and suggest their broader relevance for discovering conserved mechanisms of host manipulation.

Histoplasma↗
PubMed1977

Adoptive transfer of immunity from mice immunized with ribosomes or live yeast cells of Histoplasma capsulatum.

This investigation was designed to compare the role of lymphoid cells and immune serum in protective immunity induced by immunization with ribosomes or live yeast cells of Histoplasma capsulatum. Spleen cells, peritoneal cells, and serum from C3H mice immunized with Histoplasma ribosomes or live cells were transferred intravenously to separate groups of syngeneic recipients. All recipients along with a set of immunized and control mice were challenged intravenously with 4 x 10(6) yeast cells of H. capsulatum, and protection was assessed. Immunization with ribosomes or live cells provided 90 to 100% protection. Mice receiving filtered spleen cells or peritoneal cells from donors immunnized with live cells showed 90 to 100% protection; 80 to 90% protection was observed for mice receiving cells from ribosome-immunized donors. In contrast, no evidence of protection was seen in mice receiving serum from either live-cell- or ribosome-immunized mice. Peritoneal cells were far more efficient than spleen cells in adoptive transfer of immunity. The adoptive immunity in recipients persisted for at least 3 weeks after transfer, the longest period tested in the present study. These results indicate that the immunity elicited by immunization with Histoplasma ribosomes or live cells is mediated by a cellular mechanism.

Animals↗
PubMed1992

Typing of Histoplasma capsulatum by restriction fragment length polymorphisms in a nuclear gene.

We previously described yps-3, a Histoplasma-specific nuclear gene probe useful in the identification of Histoplasma capsulatum. By using restriction fragment length polymorphisms (RFLPs) of DNA detected by the yps-3 gene and mitochondrial DNA, 76 clinical and soil isolates of H. capsulatum were classified. The majority of North American isolates obtained from endemic regions of the midwestern United States were members of the previously characterized class 2, although four clinical isolates from different patients with AIDS from that region were grouped in class 1 with the temperature-sensitive Downs strain. A Florida soil isolate (FLS1) was placed in class 4 on the basis of RFLP with both probes. Two American Type Culture Collection strains (G184B and G186B) from Panama were grouped into class 3 by this analysis. A group of five H. capsulatum isolates obtained from patients with AIDS in New York City were typed into a new class 5 on the basis of yps-3 polymorphisms; those organisms fell into two broad mitochondrial DNA patterns, designated 5b and 5c. Two new isolates from Panama were also members of this broad yps-3 class 5 group, but they exhibited a distinct mitochondrial DNA profile (class 5a). A sixth class was detected in DNA obtained from a patient with AIDS from Panama; that DNA had unique RFLP profiles with respect to both probes. These observations suggest that the Histoplasma-specific yps-3 gene probe is a sensitive tool for typing H. capsulatum in clinical specimens. Additionally, these studies provide molecular support for the hypothesis that AIDS-associated histoplasmosis in nonendemic areas is due to reactivation of a previously acquired infection.

Acquired Immunodeficiency Syndrome↗
PubMed1979

Lymphocyte stimulation by yeast phase Histoplasma capsulatum in presumed ocular histoplasmosis syndrome.

We measured skin reactions serum antibody, and lymphocyte stimulation to Histoplasma antigens in a series of patients with presumed ocular histoplasmosis syndrome and in controls. The most sensitive test, lymphocyte stimulation to H. capsulatum sonicate, also correlated with severity of the disease. Lymphocyte stimulation to Histoplasma may be a useful adjunct to the monitoring of presumed ocular histoplasmosis syndrome.

Antibodies, Fungal↗
PubMed1978

Significance of thymus-derived lymphocytes in immunity elicited by immunization with ribosomes or live yeast cells of Histoplasma capsulatum.

The lymphoid cells responsible for protective immunity to histoplasmosis were characterized. Adoptive transfer of spleen and peritoneal cells treated with antiserum to theta-antigen from mice immunized with ribosomes or live yeast cells of Histoplasma capsulatum abrogated the ability of these cells to protect the syngeneic recipients, whereas treatment of lymphoid cells with antiserum to IgG did not affect the immunity. Prior removal of glass-adhering cells from spleen and peritoneal cell suspensions did not alter their protective activity. Treatment with mitomycin C, an antimitotic agent, ablated the capacity of immune lymphocytes to protect the syngeneic recipients. These results indicate that the immune spleen and peritoneal cells that confer immunity to histoplasmosis are thymus-dependent (T) lymphocytes and that their active proliferation in the recipients is necessary for expression of the protective immunity. Furthermore, the immunity elicited by immunization with histoplasma ribosomes and live yeast cells is mediated by a similar mechanism.

Adhesiveness↗
PubMed1977

Cell wall studies of Histoplasma capsulatum and Blastomyces dermatitidis using autologous and heterologous enzymes.

Enzymes capable of hydrolyzing cell walls of Blastomyces dermatitidis and chemotypes I and II of Histoplasma capsulatum were prepared in the laboratory or obtained from commercial sources. They included chitinases, beta-1,3-glucanases, beta-1,6-glucanase, and Pronase. Monosaccharides and disaccharides of glucose released from the cell walls by the enzymes were determined qualitatively by paper and gas-liquid chromatography, and monosaccharides were quantitated by the latter technique as well. An enzyme system isolated from Streptomyces sp. containing both chitinase and glucanase released maximum amounts of glucose and N-acetylglucosamine from the cell walls of H. capsulatum chemotype I. A chitinase preparation, free of glucanase, from Serratia marcescens released only chitobiose and N-acetylglucosamine from chemotype I cell walls, but the total quantity of N-acetylglucosamine released was about 60% less than that released by the Streptomyces system. A beta-1,3-glucanase from Bacillus circulans hydrolyzed the cell walls of H. capsulatum chemotype I, but a beta-1,6-glucanase failed to release glucose from the same walls. Autolytic enzymes, viz., beta-1,3-glucanases and several glycosidases were detected as constitutive enzymes in both yeast and mycelial phases of B. dermatitidis and H. capsulatum chemotypes I and II. No difference in the amount of activity was found between cell sap and culture filtrate preparations. The beta-glucanases prepared from the Histoplasma and Blastomyces strains were active on the cell walls of the yeast phases of H. capsulatum chemotypes I and II, releasing laminaribiose and glucose, but were essentially inactive on the cell walls of B. dermatitidis. Chitinase, beta-1,6-glucanase, alpha-glucanase, and alpha-glucosidase activities were absent from these fungal enzyme preparations.

Acetylglucosamine↗
PubMed1977

Characterization of antigens from type A and B yeast cells of Histoplasma capsulatum.

The antigenic composition of cytoplasmic extract and culture filtrate antigens of type A and B yeast cells of Histoplasma capsulatum grown in a synthetic medium was studied. These preparations from type A and B yeast cells contained varying amounts of protein, carbohydrates, and protein-carbohydrate complexes. The antigenic analysis of these preparations was performed by antigen-antiserum absorption with subsequent immunodiffusion and cross-immunoelectrophoresis with absorption in situ in an intermediate gel. All protein antigens observed in culture filtrate of either type A or B yeast cells were also present in the cytoplasmic extracts of the same type. The cytoplasmic extract of type A and B yeast cells each contained certain characteristic antigens that were not shared by the other type. Rocket immunoelectrophoresis with different molecular weight fractions of the antigenic preparations from both types indicated the polydisperse nature of Histoplasma yeast cell antigens.

Antigen-Antibody Reactions↗
PubMed1979

Cross-reactivity between antigens of Coccidioides immitis, Histoplasma capsulatum and Blastomyces dermatitidis in lymphocyte transformation assays.

The cross-reactivity of four Coccidioides antigens, three Histoplasma antigens, and two Blastomyces antigens were determined in lymphocyte transformation assays of 11 coccidioidin-reactive, histoplasmin-nonreactive subjects (group I), 13 coccidioidin-nonreactive, histoplasmin-reactive persons (group II), and 13 subjects who were skin test negative to both antigens (group III). Mycelial and yeast (or spherule)-phase antigens of the three fungi were included. Significant cross-reactivity was obtained with both coccidioidins, spherulin, and the alkali-soluble, water-soluble cell wall antigen of C. immitis, to the extent that the responses of histoplasmin-reactive persons were not statistically different (P > 0.05) from those of coccidioidin-reactive persons. In contrast, optimal dilutions of Histoplasma mycelial and yeast-phase lysates effectively distinguished (P < 0.01) responses of histoplasmin- and coccidioidin-reactive persons. The alkali-soluble cell wall antigen of H. capsulatum showed extensive cross-reactivity at most concentrations and was markedly stimulatory to lymphocytes of skin test-negative persons. Blastomycin elicited significant cross-reactions in histoplasmin-sensitive subjects and to a lesser extent in coccidioidin-sensitive subjects. The alkali-soluble cell wall antigen cross-reacted in cultures of histoplasmin-reactive persons but not in those of coccidioidin-reactive persons. All antigens effectively distinguished (P < 0.001) homologous responses of skin test-positive persons (groups I and II) from those of skin test-negative persons (group III). The extensive cross-reactivity in lymphocyte transformation assays in the absence of cross-reactivity in skin tests suggests that these two immune responses may be mediated by different T lymphocyte populations, may be elicited by different antigenic components, or both.

Antigens, Fungal↗
PubMed1977

Histoplasma capsulatum endocarditis: report of a case following heart surgery.

Clinical, laboratory, and pathologic features of a case of Histoplasma capsulatum endocarditis in a 57-year-old white male following an open mitral commissurotomy are presented. This is the second reported case of Histoplasma endocarditis following surgery. Treatment with amphotericin B failed in these two cases, though cases of Histoplasmosis endocarditis have been successfully treated. The importance of early diagnosis and treatment is emphasized.

Cardiac Surgical Procedures↗
PubMedDate not supplied

A medium for inducing conversion of Histoplasma capsulatum var. capsulatum into its yeast-like form.

Histoplasma capsulatum var. capsulatum is a dimorphic fungus that, under special conditions, converts from its more common mycelial form to a yeast-like form. Achieving this conversion, however, has been problematical for researchers. The present study tested conversion rates in ten Histoplasma capsulatum var. capsulatum strains using seven culture media, four of which were conventional and three novel. One of our novel media, MLGema, induced complete conversion of two strains within five days of incubation at 35 degrees C, and of all strains that eventually converted by the time of the second subculturing transfer, under defined experimental conditions. MLGema is also inexpensive and easy to produce.

Culture Media↗
PubMed1978

The radiological features of Histoplasma pericarditis.

The radiographic features of pericarditis due to Histoplasma capsulatum are described in 5 children. This diagnosis is suggested when enlargement of the cardiac silhouette is associated with pneumonia, parenchymal nodules or adenopathy. These findings are particularly significant if the patient lives or has lived in an area which is endemic for histoplasmosis. While pleural effusion is rare in primary histoplasmosis, it is frequently present in patients with histoplasma pericarditis.

Adolescent↗
PubMed1978

Left atrial myxoma infected with Histoplasma capsulatum.

A patient is presented in whom a left atrial myxoma was found to be infected with Histoplasma capsulatum. Histoplasmosis has not been previously associated with this tumor, nor has any fungus without preceding bacterial endocarditis and long-term antibiotic therapy. The clinical course in foru previously reported cases of bacterially infected myxoma is reviewed. There have been 18 prior cases of Histoplasma endocarditis and in two the patients have survived. Their clinical presentation and response to therapy are also reviewed, and pertinent therapeutic conclusions drawn. The role of echocardiography in this patient's evaluation and the ultimate successful therapy are discussed.

Amphotericin B↗
PubMed1977

Histoplasma capsulatum in vessels of the choroid.

In a 3-year-old boy disseminated histoplasmosis was recognized from a liver biopsy. The patient died shortly afterwards and had foci of the disease in liver, spleen, and kidneys. Large numbers of yeast cells of Histoplasma capsulatum were found within histiocytes in other organs including the eye. This rare finding is remarkable in view of the search for Histoplasma capsulatum in the syndrome known as "so-called histoplasmosis of the choroid."

Adolescent↗
PubMed1978

Migration inhibition factor study in Histoplasma capsulatum.

Mice sublethally infected with viable Histoplasma capsulatum or immunized with merthiolate-killed yeast phase cells showed decreased mortality on subsequent challenge infection as compared to controls. Migration inhibition (MI) assays using peritoneal and spleen cells from immunized but unchallenged mice showed no parallel correlation with percent mortality. MI assay indices fluctuated without concomitant changes in resistance to challenge injection with live yeast phase cells. Viable vaccines induced greater resistance to challenge infection than killed cells, although both were comparable in sensitizing ability as measured by MI assay techniques with this mouse model.

Animals↗