Reversed helper/suppressor T-lymphocyte ratio in bronchoalveolar lavage fluid from patients with breast cancer and Pneumocystis carinii pneumonia

Immunogenicity and protective efficacy of a pan-fungal vaccine in preclinical models of aspergillosis, candidiasis, and pneumocystosis

Invasive fungal infections cause over 1.5 million deaths worldwide. Despite increases in fungal infections as well as the numbers of individuals at risk, there are no clinically approved fungal vaccines. We produced a "pan-fungal" peptide, NXT-2, based on a previously identified vaccine candidate and homologous sequences from Pneumocystis, Aspergillus,Candida, and Cryptococcus. We evaluated the immunogenicity and protective capacity of NXT-2 in murine and nonhuman primate models of invasive aspergillosis, systemic candidiasis, and pneumocystosis. NXT-2 was highly immunogenic and immunized animals had decreased mortality and morbidity compared to nonvaccinated animals following induction of immunosuppression and challenge with Aspergillus, Candida, or Pneumocystis. Data in multiple animal models support the concept that immunization with a pan-fungal vaccine prior to immunosuppression induces broad, cross-protective antifungal immunity in at-risk individuals.

A Phase II Study Evaluating the Safety and Efficacy of Sunitinib Malate in Combination With Weekly Paclitaxel Followed by Doxorubicin and Daily Oral Cyclophosphamide Plus G-CSF as Neoadjuvant Chemotherapy for Locally Advanced or Inflammatory Breast Cancer

INTRODUCTION

Neoadjuvant chemotherapy is standard treatment for locally advanced breast cancer (LABC) or inflammatory breast cancer (IBC). We hypothesized that adding sunitinib, a tyrosine kinase inhibitor with antitumor and antiangiogenic activity, to an anthracycline and taxane regimen would improve pathologic complete response (pCR) rates to a prespecified endpoint of 45% in patients with HER2-negative LABC or IBC.

METHODS

We conducted a multicenter, phase II trial of neoadjuvant sunitinib with paclitaxel (S+T) followed by doxorubicin and cyclophosphamide plus G-CSF for patients with HER2-negative LABC or IBC. Patients received sunitinib 25 mg PO daily with paclitaxel 80 mg/m² IV weekly ×12 followed by doxorubicin 24 mg/m² IV weekly + cyclophosphamide 60 mg/m² PO daily with G-CSF support. Response was evaluated using pCR in the breast and the CPS + EG score (clinical-pathologic scoring + estrogen receptor [ER] and grade).

RESULTS

Seventy patients enrolled, and 66 were evaluable for efficacy. Eighteen patients (27%) had pCR in the breast (10 had ER⁺ disease and 8 had triple-negative disease). When defining response as pCR and/or CPS + EG score ≤2, 31 (47%) were responders. In pateints with ER positive disease, 23 (64%) were responders. The most common toxicities were cytopenias and fatigue.

CONCLUSIONS

Neoadjuvant S+T followed by AC+G-CSF was safe and tolerable in LABC and IBC. The study did not meet the prespecified endpoint for pCR; however, 47% were responders using pCR and/or CPS + EG score ≤2. ER positive patients had the highest response rate (64%). The addition of sunitinib to neoadjuvant chemotherapy may provide promising incremental benefit for patients with ER positive LABC.

Early variations in lymphocytes and T lymphocyte subsets are associated with radiation pneumonitis in lung cancer patients and experimental mice received thoracic irradiation

There were no ideal markers to predict the development of radiation pneumonitis (RP). We want to investigate the value of variations of lymphocytes and T lymphocyte subsets in predicting RP after radiotherapy (RT) of lung cancer based on previous clinical findings. A total of 182 lung cancer patients who received RT were retrospectively analyzed. Circulating lymphocytes and T lymphocyte subsets were measured before, during, and after RT. Patients were evaluated from the start of RT to 6 months post‐RT. A mice model with acute radiation‐induced lung injury was established and circulating lymphocytes were measured weekly until 8 weeks after irradiation. Univariate and multivariate analyses were adopted to identify risk factors of RP. Lymphocyte levels significantly decreased (P < .001) in patients before RP symptoms developed that also was able to be seen in the mice model and the values recovered during remission of symptoms. The decrease in lymphocyte count reflected the severity of RP. Meanwhile, CD4⁺ T lymphocyte count was significantly lower during the occurrence of symptoms in patients with RP than in those without RP (P < .001), and it improved along with RP recovery. Levels of lymphocytes and CD4⁺ T lymphocyte subsets proved as independent predictors of RP. Here we showed that lower peripheral blood levels of lymphocytes and CD4⁺ T lymphocyte were associated with an increased risk of RP, which was validated by this mice model, and thus are associated with differences in radiation‐induced lung toxicity among individuals and help identify those who are susceptible to developing RP after RT.

Pneumocystis Carinii Pneumonia in Adult Non-HIV Disorders

Pneumocystis carinii pneumonia (PCP) remains a serious infection in the immunocompromised host (in the absence of HIV infection) and presents significant management and diagnostic challenges to ICU physicians. Non-HIV PCP is generally abrupt in onset, and follows a fulminate course with high rates of hospitalization, ICT admission, respiratory failure, and requirement for intubation. Mortality is generally high, especially if mechanical ventilation is required. Non-invasive ventilatory support may be considered, although the rapid progression to respiratory failure often necessitates intubation at the time of presentation. Bronchoscopy is often required to establish the diagnosis, and empirical antimicrobial treatment specifically targeted to P. carinii should be initiated while awaiting confirmation. Adjunctive corticosteroids may accelerate recovery, although their use has not yet been established in non-HIV PCP. For the ICU physicians to diagnose PCP, the non-specific presentation of an acute febrile illness and respiratory distress with diffuse pulmonary infiltrates requires a high clinical index of suspician, familiarity with clinical conditions associated with increased risk for PCP, and a low threshold for bronchoscopy to establish the diagnosis.

Cellular and cytokine changes in the alveolar environment among immunocompromised patients during Pneumocystis jirovecii infection

Limited data exist on the cytokine and cellular changes in the alveolar environment in immunocompromised patients during Pneumocystis jirovecii infection. A cellular and a cytokine analysis were performed on bronchoalveolar lavage (BAL) samples from three groups of patients, i.e., an initial study group of 64 immunocompromised P. jirovecii-positive individuals and two control groups of P. jirovecii-negative patients who had been or not immunosuppressed (65 patients). The results were related to alveolar dilution as determined by urea measurement. Compared with non-infected groups, P. jirovecii-infected patients had a lower level of alveolar macrophages (AM), particularly those with high burdens of P. jirovecii. Alveolar macrophages over-expressed the Dectin-1 receptor, which was largely implicated in P. jirovecii clearance. The alveolar CD8+T and CD4+T lymphocyte counts were increased and an inverse correlation was observed between the alveolar CD4+ cell count and the P. jirovecii burden. Although the alveolar IL-6 level was considerably increased, alveolar IL-17, IL-10, TNF-α, TGF-β concentrations of P. jirovecii patients were not different from the control groups. Changes in the pulmonary environment were also highlighted during P. jirovecii colonization. Our study suggests that there is a correlation between the P. jirovecii burden in the alveolus (from colonization to a high P. jirovecii burden), and the degree of impairment of the alveolar immune response.

Lymphopenia associated with adjuvant anthracycline/ taxane regimens

BACKGROUND

We observed 2 cases of Pneumocystis carinii pneumonia (PCP) occurring in HIV-negative patients during treatment with dose-dense chemotherapy with doxorubicin/cyclophosphamide (AC) followed by paclitaxel (T). These represent the first case reports of PCP occurring during dose-dense chemotherapy for breast cancer. Because lymphocyte depletion is thought to predispose patients to PCP, we explored whether the shortened intervals between cycles during dose-dense chemotherapy might place patients at risk for lymphocyte depletion and thereby a potentially increased risk of opportunistic infection.

PATIENTS AND METHODS

Three cohorts of patients were analyzed. Cohort 1 involved 135 patients receiving dose-dense AC --> T on a phase II study. Cohort 2 included 64 patients who received treatment with dose-dense AC --> albumin-bound paclitaxel on a phase II clinical trial. Cohort 3 consisted of 59 patients who received AC --> T given every 3 weeks who were identified from the Clinical Research Information System database at Dana-Farber Cancer Institute. For cohorts 1 and 3, the electronic medical record was reviewed to determine absolute lymphocyte counts (ALCs) and absolute neutrophil counts (ANCs) for day 1 of each of the 8 cycles of treatment. For cohort 2, data was prospectively collected and entered into an electronic database. The lowest ALC obtained by each patient on day 1 of any cycle was termed the nadir.

RESULTS

Patients experienced grade 3 (ALC < 500 cells/mm3) or grade 4 (ALC < 200 cells/mm3) lymphopenia in all 3 cohorts: 63% with dose-dense AC -->T, 23.4% in dosedense AC --> albumin-bound paclitaxel, and 69% with dose-dense AC --> T every 3 weeks. Patients experienced their lowest median ALC count at cycle 5 of treatment in all 3 cohorts, with a median nadir of 400 cells/mm3 in cohort 1, 690 cells/mm3 in cohort 2, and 400 cells/mm3 in cohort 3.

CONCLUSION

The majority of patients receiving AC --> T every 2 or 3 weeks experience grade 3/4 lymphopenia. Median lymphocyte counts appear to be lowest around cycle 5, the point at which we observed 2 cases of PCP. Lymphocyte counts appear to be reaching a low enough level to place patients at risk for opportunistic infection during treatment with dosedense AC --> T and with AC --> T given every 3 weeks.

Association of Chronic Obstructive Pulmonary Disease Severity andPneumocystisColonization

Factors modulating the variable progression of chronic obstructive pulmonary disease (COPD) are largely unknown, but infectious agents may play a role. Because Pneumocystis has previously been shown to induce a CD8(+) lymphocyte- and neutrophil-predominant response similar to that in COPD, we explored the association of the organism with accelerated disease progression. We examined Pneumocystis colonization rates in lung tissue obtained during lung resection or transplantation in smokers with a range of airway obstruction severity and in a control group with lung diseases other than COPD. Using nested polymerase chain reaction, Pneumocystis colonization was detected in 36.7% of patients with very severe COPD (Global Health Initiative on Obstructive Lung Disease [GOLD] Stage IV) compared with 5.3% of smokers with normal lung function or less severe COPD (Stages 0, I, II, and III) (p = 0.004) and with 9.1% of control subjects (p = 0.007). Colonized subjects exhibited more severe airway obstruction (median FEV(1) = 21% predicted versus 62% in noncolonized subjects, p = 0.006). GOLD IV was the strongest predictor of Pneumocystis colonization (odds ratio = 7.3, 95% confidence interval = 2.4-22.4, p < 0.001) and was independent of smoking history. We conclude that there is a strong association between Pneumocystis colonization and severity of airflow obstruction in smokers, suggesting a possible pathogenic link with COPD progression.

Pneumocystis carinii pneumonia as a complication of bendamustine monotherapy in a patient with advanced progressive breast cancer

BACKGROUND

Bendamustine is an alkylator with anticipated antimetabolic activity. It has shown activity in malignant lymphoma, multiple myeloma, and breast cancer. Recognized side-effects are relatively mild with myelosuppression as the dose-limiting toxicity. The CD4/CD8 ratio may be reduced. To what extent the alteration of lymphocytes, especially CD4(+) lymphocytes, correlates with an increase in opportunistic infections cannot be definitively answered.

CASE REPORT

The patient, female, aged 48 years, was suffering from an advanced progressive breast cancer. After initial treatment with several chemotherapies, a cytotoxic therapy was initiated, with bendamustine (150 mg/m(2)) administered on two consecutive days and repeated every 4 weeks. After five courses, the patient developed Pneumocystis carinii pneumonia (PCP), disclosed in the bronchoalveolar lavage. While receiving bendamustine therapy, the CD4(+) and CD8(+) lymphocyte counts in the peripheral blood were determined by flow cytometry. The next-to-normal CD4/CD8 ratio before therapy (0,82) had decreased to 0,05 during the therapy mainly due to a decline of CD4(+) lymphocyte. The patient was seronegative for human immunodeficiency virus. In spite of high-dose intravenous trimethoprim/sulfamethoxazole and methylprednisolone application, the patient died of a respiratory failure 3 days after PCP was diagnosed.

CONCLUSION

Bendamustine is capable of inducing a reduction in CD4(+) lymphocyte counts causing a severe T-lymphocyte-mediated immunosuppression. Measuring CD4(+) lymphocyte counts may be helpful in determining the risk of PCP in patients treated with bendamustine.

Alterations in T lymphocyte profiles of bronchoalveolar lavage fluid from SIV- and Pneumocystis carinii-coinfected rhesus macaques

The goal of this study was to examine SIV- and Pneumocystis carinii-coinfected rhesus macaques as a model of P. carinii infection in HIV-seropositive humans. The influence of P. carinii infection on the cellular composition of bronchoalveolar lavage (BAL) fluid from SIV-infected and normal rhesus macaques was examined by flow cytometric analysis and polymerase chain reaction (PCR). BAL fluid from SIV- and P. carinii coinfected macaques showed a substantial T lymphocyte influx composed of more than 90% CD8+ T cells. These results are in contrast to BAL fluid from SIV-infected macaques with no detectable P. carinii-specific PCR product, where CD4+ T cells were present in significant numbers and the CD8+ T cell population was less than 70% of total CD3+ lymphocytes. We observed no significant differences in peripheral blood CD4+ or CD8+ T cell levels in the SIV-infected animals, regardless of P. carinii status, indicating that the CD8+ T cell infiltration in the lungs of the P. carinii-positive animals was likely the result of P. carinii infection. These results demonstrate that although peripheral blood CD4+ T cell levels are predictive of susceptibility to P. carinii infection in this model, the levels are not reflective of the T cell profile in the lung during SIV and P. carinii coinfection. The SIV- and P. carinii-coinfected macaques showed a spectrum of lung disease severity that was histologically similar to human P. carinii pneumonia (PCP). Interestingly, even mild P. carinii infection was sufficient to alter the normal CD4+/CD8+ T cell profiles in the lungs of SIV-infected rhesus macaques. These results are similar to immunologic findings in human AIDS-associated PCP and support the usefulness of this model in the study of immune responses to P. carinii.

Lung abscess in adults: clinical comparison of immunocompromised to non-immunocompromised patients

Information related to the clinical characteristics and isolated microbes associated with lung abscesses comparing immunocompromised (IC) to non-immunocompromised (non-IC) patients is limited. A retrospective review for 1984-1996 identified 34 consecutive adult cases of lung abscess (representing 0.2% of all cases of pneumonia), including 10 non-IC and 24 IC patients. Comparison of age, gender, tobacco use, pre-existing pulmonary disease or recognized aspiration risk factors were not significantly different between the two groups. Upper lobe involvement accounted for the majority of cases, although multi-lobe involvement was limited to IC patients. There were no differences in the need for surgical intervention, and mortality was very low for both groups. Anaerobes were the most frequent isolates for non-IC patients (30%), whereas aerobes were the most frequent isolate for IC patients (63%). Importantly, certain organisms were exclusively isolated in the IC group and multiple isolates were obtained only from the IC patients.Thus, comparing non-IC to IC patients, clinical characteristics may be similar whereas important differences may exist in the microbiology associated with lung abscess. These findings have important implications for the clinical management of these patient groups, and support a strategy to aggressively identify microbial agents in abscess material.

Pneumocystis carinii pneumonia in patients without HIV infection

Pneumocystis carinii is an important, but sporadic, opportunistic pulmonary pathogen in immunosuppressed HIV seronegative persons. Historically, patients at highest risk for P. carinii pneumonia are included infants with severe malnutrition, children with primary immunodeficiencies, patients with hematological malignancies, and recipients of solid organ or bone marrow transplants. Recently, solid tumor patients, in particular those receiving high-dose corticosteroids for brain neoplasms, and patients with inflammatory or collagen-vascular disorders, especially patients with Wegener granulomatosis receiving immunosuppressive therapy, have been identified as subgroups at increased risk for P. carinii pneumonia. Other factors associated with P. carinii pneumonia include the intensity of the immunosuppressive regimen and tapering doses of corticosteroids. Because P. carinii pneumonia is associated with significant morbidity and mortality, it is important to identify high-risk patient populations to administer effective chemoprophylactic agents, such as trimethoprim-sulfamethoxazole.

Peripheral blood CD4 + T-lymphocyte counts during Pneumocystis carinii pneumonia in immunocompromised patients without HIV infection

STUDY OBJECTIVES

To assess the potential use of peripheral blood CD4 + T-lymphocyte counts (CD4 + counts) as a clinically useful biological marker to identify specific immunocompromised patients (without HIV infection) at high risk for Pneumocystis carinii pneumonia (PCP).

DESIGN

Prospective observational study.

SETTING

Three hundred seventy-five-bed tertiary-care urban referral teaching hospital, and 250-bed community-based referral hospital.

PATIENTS

One hundred seventy-one consecutive confirmed HIV-seronegative hospitalized and ambulatory adults, including 22 patients with active PCP, 8 patients with bacterial pneumonia, 24 persons in two groups considered at high clinical risk, 38 persons in two groups considered at low or undefined risk, and 79 persons in four groups considered not at risk for PCP (including healthy individuals).

MEASUREMENTS AND RESULTS

Compared to counts in healthy individuals, median CD4 + counts were significantly decreased in patients with active PCP (61 cells/microL vs 832 cells/microL; p = 0.001) where 91% of patients had a CD4 + count < 300 cells/microL at the time of PCP diagnosis. Median CD4 + counts were also reduced in the high clinical risk groups of recent organ transplant recipients (117 cells/microL; p = 0.007), 64% with < 300 cells/microL, and patients receiving chemotherapy (221 cells/microL; p<0.01), 80% with < 300 cells/microL. For the low or undefined clinical risk groups, the median CD4 + counts were not significantly reduced, although 39 to 46% of individuals receiving long-term corticosteroid therapy (alone or in combination with other agents) had CD4 + counts < 300 cells/microL. Median CD4 + counts in individuals considered not at risk for PCP were similar to those in healthy subjects. Compared to counts in patients with active PCP, median CD4 + counts were significantly higher in bacterial pneumonia patients (486 cells/microL; p<0.05), but similar to those in healthy subjects.

CONCLUSIONS

These data suggest that for immunosuppressed persons without HIV infection (especially in low or undefined PCP risk groups), CD4 + counts may be a useful clinical marker to identify specific individuals at particularly high clinical risk for PCP and may help to guide chemoprophylaxis.

Serial transplants of DMBA-induced mammary tumors in fischer rats as model system for human breast cancer: V. Myoepithelial-mesenchymal conversion during passaging as possible cause for modulation of pineal-tumor interaction

An elevation of melatonin secretion parallel to an enhanced production of macrophage-derived biopterin was observed in female F344 Fischer rats bearing passage 2 serial transplants derived from a malignant mammary tumor induced by 7,12-dimethylbenz[a]anthracene (DMBA). As opposed to that both parameters were depressed at passage 12. These results indicate the presence of divergent immunoneuroendocrine interactions during different phases of tumor growth. Since these biochemical events must have their common origin in changes taking place within these tumor transplants the current histopathological study was initiated. The primary tumor used for serial transplantation was a moderately differentiated adenocarcinoma of the mammary gland showing cytokeratin-positive epithelial components located in the inner epithelial tubule layer. In addition, bland-looking round or elongated actin-positive myoepithelial cells were detected which apart from epithelial cells are known to constitute the main cellular components of the mammary ductal system which resemble smooth muscle cells both morphologically and functionally. The tumor of passage 1 showed glandular tubules, lined by an inner epithelial layer, and many nests of clear, bland-looking actin-positive myoepithelial cells lying around tubules as well as in the stroma between actin-negative epithelial elements. The tumor of passage 2 used for transplantation consisted of a chaotic mixture of epithelial carcinomatous cells, forming a few irregular small tubules or solid nests, and, predominantly, of elongated plump or spindle-shaped, "myoid" atypical myoepithelial cells with a strong actin-positive reaction and some of these cells showed a focal vimentin expression. The tumor was characterized as a carcinosarcoma. At passage 12 epithelial cells were not identified. The tumor displayed features of a pleomorphic sarcoma consisting mainly of giant cells with bizarre nuclei being cytokeratin- and desmin-negative, weakly vimentin-positive but strongly actin-positive. These results indicate that DMBA-induced mammary tumor cells in female F344 Fischer rats undergo dramatic morphological changes during serial transplantation characterized by a total loss of malignant epithelial (carcinomatous) cells and the emergence and subsequent predominance of malignant (sarcomatous) mesenchymal cells. It appears that these sarcomatous cells develop out of myoepithelial cells since atypical myoepithelial cells with a strong actin-positive reaction showed a focal vimentin expression at passage 2 indicating myofibroblastic differentiation as part of mesenchymal transition. The loss of epithelial cell elements as well as a parallel transition of myoepithelial to mesenchymal cell elements during passaging could lead to a lack of immunological recognition of these tumor transplants and to depression of melatonin. Possible mechanisms involved in these phenomena as well as the relevance of these findings for a better understanding of the role of melatonin in human mammary cancer are discussed.

Use of adjunctive corticosteroids in severe adult non-HIV Pneumocystis carinii pneumonia

STUDY OBJECTIVE

To examine the use of adjunctive corticosteroids in cases of severe Pneumocystis carinii pneumonia (PCP) in non-HIV-infected adult patients.

DESIGN

Retrospective review of medical records.

SETTING

Tertiary care urban teaching hospital.

PATIENTS

Review identified 31 consecutive histologically confirmed primary cases of adult non-HIV-related PCP. Complete records were available for 30 patients, including 20 male and 10 female patients with a mean age of 58.3+/-15 years (+/-SD). Underlying conditions included organ transplantation (n=13), long-term immunosuppressive therapy (n=9), and chemotherapy for malignancy (n=8). All patients had documented PO2 <65 mm Hg or arterial oxygen saturation <90% on room air.

INTERVENTIONS

Following the identification of P carinii, in addition to trimethoprim-sulfamethoxazole or pentamidine therapy, 16 patients received increased steroids (> or =60 mg prednisone daily equivalent; increased high-dose steroid group), whereas 14 patients were maintained on a regimen of low doses (< or =30 mg prednisone equivalent daily) or had steroid therapy tapered (low-dose steroid group).

RESULTS

The increased high-dose steroid group demonstrated a shorter required duration for mechanical ventilation (6.3+/-6 days vs 18.0+/-21 days; p=0.047), a shorter duration of ICU admission (8.5+/-7 days vs 15.8+/-8 days; p=0.025), and a shorter duration of supplemental oxygen use (10.0+/-4 vs 32.2+/-33; p=0.05). The hospital duration to discharge for the nine survivors in each group favored the use of corticosteroids (15.4+/-5 days vs 36.3+/-33 days; p=0.077). Similar rates were observed for intubation (75% vs 57%; p=0.442) and in-hospital mortality (44% vs 36%; p=0.722).

CONCLUSIONS

These preliminary data suggest that high-dose adjunctive corticosteroids may accelerate recovery in cases of severe adult non-HIV PCP.

The role of alveolar macrophages in Pneumocystis carinii degradation and clearance from the lung

Although studies indicate that alveolar macrophages participate in host defense against Pneumocystis carinii, their role in organism degradation and clearance from the lung has not yet been established. We, therefore, quantified the uptake and degradation of 35S-labeled P. carinii by cultured macrophages, demonstrating significant degradation of P. carinii over 6 h. We further evaluated the role of macrophages in elimination of P. carinii from the living host. Rats received either intratracheal PBS, liposomal PBS (L-PBS), or liposomal dichloromethylene diphosphonate (L-Cl2MDP), a preparation which leads to selective depletion of macrophages. Over 72 h, L-Cl2MDP-treated animals had loss of > 85% of their alveolar macrophages. In contrast, L-PBS-treated rats had cellular differentials identical to rats receiving PBS. Macrophage-depleted rats and controls were next inoculated with P. carinii and organism clearance was determined after 24 h. P. carinii elimination was evaluated with both cyst counts and an ELISA directed against glycoprotein A (gpA), the major antigen of P. carinii. Both assays indicated that macrophage-depleted rats had substantial inpairment of P. carinii clearance compared to L-PBS- or PBS-treated rats. These data provide the first direct evidence that macrophages mediate elimination of P. carinii from the living host.

Fibroblast heterogeneity in the periodontium and other tissues

Fibroblasts are the major resident cells which inhabit the periodontal tissues. As such, they are crucial for maintaining the connective tissues which support and anchor the tooth. Little is known of their origins, synthesis of regulatory cytokines and growth factors in health and disease, and importance in soft tissue regeneration. An emerging concept is that fibroblasts are not homogeneous, but instead consist of subsets of cells which can regulate bone marrow-derived cells such as T lymphocytes. Fibroblasts can be separated into subsets on the basis of morphology, size and expression of intermediate filaments as well as collagen subtypes. Differential surface marker expression has also been a key feature to distinguish fibroblast subsets from many tissues. Antigens such as Thy-1, class II MHC, and C1q are among those surface proteins which have been employed successfully to separate fibroblasts. Importantly, these fibroblast subsets are not only antigenically diverse, but also possess distinct functions. Thy 1+ pulmonary fibroblasts can display class II MHC antigens, synthesize IL-1 and can activate T lymphocytes, whereas the Thy 1+ subset is devoid of these functions. Recently, fibroblasts from the human orbit have also been shown to be separable on the basis of Thy 1 surface marker expression. Fibroblasts derived from human gingiva and periodontal ligament also appear to be composed of subsets with a heritable pattern of surface markers which will permit their separation into functional subpopulations. This paper will review findings of fibroblast heterogeneity in periodontal and other tissues. Evidence will be presented for the use of surface markers to delineate functional subsets. The ability to discriminate subsets of fibroblasts will aid in studies of periodontal disease pathogenesis and wound healing.

Pneumocystis carinii pneumonia in patients without acquired immunodeficiency syndrome: associated illness and prior corticosteroid therapy

OBJECTIVE

To determine the clinical spectrum of immunosuppressive conditions and systemic corticosteroid therapy associated with the development of Pneumocystis carinii pneumonia in a consecutive series of patients without acquired immunodeficiency syndrome (AIDS).

DESIGN

We retrospectively analyzed a consecutive series of 116 patients without AIDS who were assessed at Mayo Medical Center for a first episode of P. carinii pneumonia between 1985 and 1991.

METHODS

Medical records were examined to determine underlying immunosuppressive disorders, premorbid corticosteroid dosage and duration of therapy, associated infections, and subsequent respiratory failure and in-hospital mortality.

RESULTS

Conditions associated with a first episode of P. carinii pneumonia were hematologic malignant disorders (30.2%), organ transplantation (25.0%), inflammatory disorders (22.4%), solid tumors (12.9%), and miscellaneous conditions (9.5%). Regardless of the associated underlying disease, corticosteroids had been administered systemically in 105 patients (90.5%) within 1 month before the diagnosis of P. carinii pneumonia. The median daily corticosteroid dose was equivalent to 30 mg of prednisone; however, 25% of patients had received as little as 16 mg of prednisone daily. The median duration of corticosteroid therapy was 12 weeks before the development of pneumonia; however, P. carinii pneumonia developed after 8 weeks or less of corticosteroid therapy in 25% of these patients. Respiratory failure occurred in 43%, and in-hospital mortality was 34% for patients with P. carinii pneumonia in conditions other than AIDS.

CONCLUSION

Although these results do not suggest that premorbid administration of corticosteroids is the only factor that contributes to the development of P. carinii pneumonia in these patients, they show that, in this large consecutive series, systemic corticosteroid therapy, even in moderate doses, was administered to most patients during the month preceding the onset of P. carinii pneumonia. Consideration should be given to instituting P. carinii prophylaxis (when not contra-indicated) in patients for whom prolonged systemic corticosteroid therapy is prescribed.

Pulmonary lymphangitic metastasis from breast cancer. Lymphocytic alveolitis is associated with favorable prognosis

BACKGROUND

More than 20 percent of patients with breast cancer have pulmonary lymphangitic spread at death. Previous reports have indicated that some patients may respond to aggressive chemotherapy that includes corticosteroids.

METHODS

Bronchoscopy with bronchoalveolar lavage (BAL) was used to assess pulmonary infiltrates in 14 patients with infiltrating ductal breast cancer. All patients had received prior cytotoxic or hormonal therapy. Following a diagnosis of pulmonary metastasis by BAL or biopsy specimen, all patients received prednisone and chemotherapy.

RESULTS

BAL confirmed the diagnosis of metastatic tumor in 10 of 14 patients. The conditions of the remaining patients were diagnosed by one or more other bronchoscopy specimens. Patients were divided into two groups based on BAL lymphocyte percentage (10 percent is the upper limit of normal in our laboratory). Seven patients had > 10 percent lymphocytes (high lymphs: 26 +/- 11.6 percent [mean +/- SD]) compared with seven patients with normal lymphocyte percentage (low lymphs: 4 +/- 1.9 percent, p < 0.01). Six of seven patients with low lymphs died within three months of BAL compared with one in seven patients with high lymphs (p < 0.01). Within six months, all patients with low lymphs were dead whereas five of seven patients with high lymphs were alive, (p < 0.01). Comparing the two groups, there was no significant difference in percentage of BAL neutrophils, patient age, duration of disease prior to diagnosis, or arterial-alveolar oxygen gradient.

CONCLUSION

In breast cancer patients with pulmonary lymphangitic metastasis, a lymphocytic alveolitis is associated with a better overall prognosis.

Pharmacological modulation of inhaled sodium metabisulphite-induced airway microvascular leakage and bronchoconstriction in the guinea-pig

1. We have investigated the effects of chlorpheniramine, atropine and capsaicin pretreatment on inhaled sodium metabisulphite (MBS)-induced airway microvascular leakage and bronchoconstriction in anaesthetized guinea-pigs in order to clarify the mechanisms involved in these responses. The effects of frusemide and nedocromil sodium were also examined. 2. Lung resistance (RL) was measured for 6 min after inhalation of MBS (20, 40, 80 and 200 mM; 30 breaths), followed by measurement of extravasation of Evans blue dye into airway tissues, used as an index of airway microvascular leakage. MBS caused an increase in RL and leakage of dye at all airway levels in a dose-dependent manner. 3. Chlorpheniramine (10 mg kg-1, i.v.), atropine (1 mg kg-1, i.v.), their combination or inhaled nedocromil sodium (10 mg ml-1, 7 min) had no effect against the airway microvascular leakage induced by 80 mM MBS (30 breaths). Capsaicin pretreatment (50 mg kg-1, s.c.) caused a significant decrease in the leakage of dye in the main bronchi and inhaled frusemide (10 mg ml-1, 7 min) also in the main bronchi and proximal intrapulmonary airway. 4. Chlorpheniramine, atropine, their combination, capsaicin pretreatment and frusemide, but not nedocromil sodium, inhibited significantly the peak RL induced by 80 mM MBS (30 breaths) by approximately 50%. 5. We conclude that a cholinergic reflex and neuropeptides released from sensory nerve endings may participate in the mechanisms of MBS-induced airway responses. Frusemide but not nedocromil sodium may have an inhibitor effect on these neural mechanisms. The inhibitory effect of nedocromil sodium against lower doses of MBS is not excluded.