Interferon production during the course of Mycoplasma pneumoniae infection.

In patients infected with Mycoplasma pneumoniae the development of interferon (IFN) was studied in nasopharyngeal secretions and sera. The production of IFN-gamma by lymphocytes was also investigated in response to M. pneumoniae antigen and mumps virus antigen. IFN-alpha was detected in 25 (61.0%) of 41 nasopharyngeal secretion samples and in 25 (59.5%) of 42 serum samples within 6 days after the onset of illness. IFN-alpha was significantly higher in nasopharyngeal secretions than in sera and a significant correlation was observed between the two. In most of the patients lymphocytes produced a larger amount of IFN-gamma in the convalescent stage than in the acute stage, when lymphocytes were stimulated with M. pneumoniae antigen. In some patients, however, lymphocytes did not produce IFN-gamma during the course of illness. Such lymphocytes, negative for IFN-gamma production in response to M. pneumoniae, produced IFN-gamma after the depletion of macrophages, and readdition of macrophages suppressed the production of IFN-gamma by lymphocytes. When lymphocytes were stimulated with heterogeneous antigen (mumps virus), they produced no IFN or a small amount of IFN in the acute stage of M. pneumoniae infection, and IFN production increased in the convalescent stage. Different mechanisms seem to work for homogeneous and heterogeneous antigens in the suppression of IFN production in M. pneumoniae infection.

A field trial, using killed-Mycoplasma gallisepticum vaccine to protect against chicken respiratory mycoplasmosis.

In a field trial with chickens, the efficacy of killed Mycoplasma gallisepticum vaccine against respiratory mycoplasmosis was determined. Broiler chickens were vaccinated by aerosol administration at 3, 14, and 25 days of age, and observations were made of survival rate, body weight gain ratio, macroscopic lesion grade of airsacculitis, isolation of organisms, serologic test results, histopathologic changes, and clinical signs. Inhalation of the vaccinal aerosol did not influence livability and body weight gain ratios. In the control group, M gallisepticum, M synoviae, or both, wereisolated in 6 of 10 chickens at age 84 days and in 1 of 10 chickens at age 134 days. In all of the vaccinated groups (10 broilers each), however, results of bacteriologic cultural examination during the observation period were negative. The killed M gallisepticum vaccine also suppressed increase of antibody titers in the tube agglutination and the hemagglutination-inhibition tests at different intervals. Both the histopathologic changes and the clinical signs appeared minimal in the vaccinated group.

Experimentally induced synovitis of chickens with Mycoplasma synoviae: effects of bursectomy and thymectomy on course of the infection for the first four weeks.

Specific pathogen-free chickens (bursectomized and x-irradiated (SBx-X), thymectomized and x-irradiated, x-irradiated, as well as nontreated) were inoculated (in the right tibiometatarsal joint) at the 4th week after hatching with a synovitis-derived Mycoplasma synoviae strain. Differences were not observed in recovery rate of mycoplasmas from tissues among these groups. The SBx-X chickens which were killed at 2 and 4 weeks after the intraarticular inoculation or which died during this period and bacteremia and severe synovitis with edema and heterophil infiltration in synovial fluid and in area from synovial membrane to subcutaneous tissue. Swelling of left leg joints or foot pads were observed mainly in the SBx-X group. A significant difference in the mortality rate and severity of airsacculitis was observed between SBx-X and other groups. The thymectomized and x-irradiated chickens did not show edema, synovial fluid, or swelling in the joint area. However, small lymph follicles composed of lymphoid and plasma cell were formed locally in synovial membranes of various joints. These results indicated that bursa-dependent lymphocytes are correlated with resistance to develop the lesions and that thymus-dependent lymphocytes are necessary for macroscopic lesions to develop.

[Protective effects of Mycoplasma pneumoniae live vaccine or its hyperimmune serum on the experimental infection in mice].

SPF-BALB/c mice in which Mycoplasma pneumoniae cell proliferation accompanied by immunological responses had been confirmed, were immunized with live vaccines or with hyperimmune sera of M. pneumoniae FH-P24 and its mutant strains (P24-S1, P24-S11), were then assayed for infection-protection. Eight weeks after the last vaccination, 70 percent protection was obtained by inoculation once or twice with live FH-P24 and P24-S1 vaccines, respectively. After 12 weeks, 80% protection was achieved by FH-P24 and 60% by P24-S1 live vaccine, while protectivity was not obtained by P24-S11 live vaccine. In case of passively immunized mice, IgG antibody titers and protective effect were not always found to be parallel. Namely, mice which were passively immunized with anti-FH-P24 serum, showed only 20% protection. However to get the above results, it was necessary that the anti-mutant strain serum be ten times higher than anti-FH-P24 serum in IgG titer. In the immunoblot analysis, sera from patients infected with M. pneumoniae immunoblotted the 168-KDa (P1 protein) and the 85-KDa protein of FH-P24 and P24-S1, but not the 85-KDa protein of P24-S11.

Mediastinal synovial sarcoma.

Synovial sarcoma of the mediastinum is a rare neoplasm that has overlapping histological and immunophenotypic features with other tumors in the differential diagnosis. We describe a case of this disease. The tumor was located at the right side of the pericardium, where an FDG-PET scan showed an uptake. It was resected, a resection which was complicated by the necessity of partially resecting the pericaridium and right middle lobe which were invaded by the tumor. The doubling time of the main tumor was 11.8 days. The margin of the resected specimen was tumor-free both macro- and microscopically. Reverse transcription-PCR confirmed the diagnosis of synovial sarcoma. The patient rejected chemotherapy or radiation therapy, and had recurrent tumors only one month after the operation. Finally, she opted to have only palliative care and died 79 days after the operation.

Favorable acute and long-term outcomes after the resection of pulmonary aspergillomas.

OBJECTIVE: This retrospective study was designed to examine the acute and long-term outcomes after surgical treatment of patients with pulmonary aspergillomas. PATIENTS AND METHODS: From 1992 to 2006, 24 patients (21 men, mean age 58.4 years) with pulmonary aspergillomas underwent pulmonary resection. Operative indications were massive or repetitive hemoptysis in 6 patients, medically unmanageable localized infection in 14 patients, and undetermined mass in 4 patients. Eighteen patients (75.0 %) had background pulmonary diseases and four patients (16.7 %) were mildly immunocompromised. Eight patients had simple aspergillomas, while sixteen patients had complex aspergillomas. Two patients with pleural empyema had their pleural spaces sterilized before pulmonary resections. Fungus balls and pulmonary cavities along with the surrounding lung were removed in all patients. RESULTS: Surgical procedures consisted of 13 lobectomies, 5 pneumonectomies including one completion pneumonectomy, 2 segmentectomies and 4 wedge resections. Postoperative complication occurred in 10 patients (41.6 %) and one patient died from aortic bleeding due to postoperative empyema. Other major complications were prolonged air leaks, bleeding, and chylothorax. In the follow-up period, all but one patient were free from aspergillosis. Hemoptysis was not seen in any patient. Overall survival rates at 2, 5, and 10 years were 86.6 %, 79.4 % and 79.4 %, respectively. Disease-free survival rates from aspergillosis were 86.6 %, 72.6 % and 72.6 % at 2, 5, and 10 years, respectively. CONCLUSION: Pulmonary resection for aspergilloma showed favorable acute and long-term outcomes when surgical treatment was applied in selected patients.

Acquired immunity to Mycoplasma pneumoniae. Pneumonia in hamsters.

An inactivated Mycoplasma pneumoniae vaccine was prepared from a culture in a liquid medium supplemented with water extract of egg yolk. Vaccinated Syrian hamsters were exposed to virulent M. pneumoniae aerosol and were examined for the retention of mycoplasmas and for histopathological changes in the respiratory tracts. When a vaccine prepared with strain FH was administered intramuscularly or by inhalation in aerosol, no significant resistance was shown with respect to mycoplasma proliferation. An increased resistance, however, was observed when an aluminium phosphate-adsorbed vaccine, and when a plain vaccine (although to a lesser degree) prepared with hamster 24-passaged strain FH, was administered intramuscularly. Histopathologically, lung lesions were markedly suppressed in groups showing high resistance. A correlation between the serum antibody titer and the resistance to infection was observed. Hamsters which received a hyperimmune rabbit antiserum intracordally showed a high resistance to M. pneumoniae infection. The suppression of histopathological changes also coincided with high complement-fixing antibody titers of either actively or passively immunized hamster serum. The results suggest that humoral immunity plays an important role in resistance to M. pneumoniae pneumonia in hamsters.

Characterization and pathogenicity of hemolysis mutants of Mycoplasma pneumoniae.

Hemolysis mutants were produced by treating Mycoplasma pneumoniae FH-P24 strain with N-methyl-N-nitro-nitrosoguanidine and were classified into three different groups. The first group of mutants, strains P24-L1, L2, and L11, showed wide and clear hemolytic zones. Their attachment ability to erythrocytes of various animals and to hamster lung cells were the same as those of the parent strain. The second group, strain P24-S1, showed non-hemolysis and non-hemadsorption, but retained the attachment ability to lung cells, although not to erythrocytes. The third group, strain P24-S11, was non-hemolytic, had completely lost the attaching ability, and did not proliferate in vivo. Strains in the first group produced significant microscopic pneumonic lesions in hamsters while strain P24-S1 produced milder lung lesions. Strain P24-S11 did not cause any lung lesions, and organisms were not recovered from the lungs of hamsters. The attachment of M. pneumoniae to respiratory epithelium as a cause of infection and the existence of a relationship between the hemolytic abilities of the organisms and histopathogenicity in the hamster lung tissue were further supported by the present data. It was also shown that the use of hemolysis mutants is useful for the elucidation of pathogenesis in mycoplasma infections.

Immunogenicity and protective effect of hemolysis mutants of Mycoplasma pneumoniae.

Two attenuated strains of Mycoplasma pneumoniae, P24-S1 and P24-S11, were tested for their ability as a live vaccine to confer on hamsters immune resistance against challenge infection with a virulent strain of M. pneumoniae, FH-P24. Fifty percent protection was obtained by vaccination with the P24-S1 strain administered once or twice. In contrast, only 10% of the animals were protected by the P24-S11 vaccine even when it was given three times. Vaccination with the P24-S1 strain resulted in higher humoral and cellular immune responses than the P24-S11 did. These results suggest that the P24-S1 strain has the primary qualities a vaccine which may be used for protection against human mycoplasmal infection.

Role of humoral antibodies in resistance to Mycoplasma pneumoniae pneumonia in hamsters.

Golden Syrian hamsters adoptively immunized with hyperimmune Mycoplasma pneumoniae rabbit antiserum, immunoglobulin (Ig) M-rich (IgM) fraction, IgG-rich (IgG) fraction, antiserum absorbed with either killed M. pneumoniae or killed Staphylococcus aureus organisms, or antiserum treated with 2-mercaptoethanol (2-ME) were examined for resistance against aerosol infection with virulent M. pneumoniae. Significant resistance to the establishment of infection in the respiratory tract was shown in hamsters pretreated with the untreated antiserum, IgG fraction or 2-ME-treated antiserum, whereas animals pretreated with the IgM fraction and the antisera absorbed with M. pneumoniae or S. aureus organisms were not significantly resistant. Histopathologically, lung lesions were markedly suppressed in animals with high resistance, but were typically pneumonic in animals with low or no resistance. The efficacy of adoptively administered serum preparations was closely related to their antibody titers. The results indicate that humoral antibody plays an important role in protection against experimental M. pneumoniae pneumonia in hamsters, although the participation of the cell-mediated immune response was not determined.

Suppressive effect of macrophages on interferon-gamma production by human peripheral lymphocytes stimulated with Mycoplasma pneumoniae.

Production of interferon (IFN)-gamma was investigated in human peripheral lymphocytes stimulated with Mycoplasma pneumoniae. Lymphocytes obtained from non-immune individuals produced no IFN. IFN-gamma was produced by T cells obtained from immune individuals, and the helper/inducer T cells produced two- to sixfold higher titer of IFN-gamma than the suppressor/cytotoxic T cells. The addition of macrophages in T cell cultures suppressed the production of IFN-gamma; this differs from the previous result wherein the addition of macrophages enhanced the production of IFN-gamma, when stimulated with mumps virus or measles virus.

Immunological responses of hamsters in the acquired immune state to Mycoplasma pneumoniae infection.

Protective effects of vaccination of hamsters against Mycoplasma pneumoniae infection, evaluated according to the recovery of mycoplasmas and histopathological changes in the respiratory tract after challenge infection, persisted for at least 6 months after the final vaccination. Serum antibody levels reached a maximum in the second week after the last vaccination and decreased markedly between the first and the third months, but increased again in sera obtained from animals given booster injections. Metabolism-inhibiting antibodies were detected in bronchial washings of animals showing high resistance obtained by vaccinal or passive immunization. Antiserum transfer was also effective for protection but cell-mediated immune responses were not demonstrated in any animals up to 6 months after the vaccination. Even after 10 months, suppression of both mycoplasmal proliferation and lung lesions was apparent, and a single dose of the vaccine induced a significant booster effect. These findings suggest that (1) humoral immunity is more important than cell-mediated immunity in resistance of hamsters to M. pneumoniae pneumonia, and (2) the antibody secreted in the respiratory tract may be involved in the local defense mechanisms.