Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0032285 (pneumonia)
 54,520 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Alveolar macrophages (AM) were obtained by bronchoalveolar lavage (BAL) from patients presenting with pneumonitis: 30 human immunodeficiency virus (HIV)-infected individuals and 12 transplant recipients. Nine normal volunteers acted as controls. The cells were washed and cytospins prepared. Monoclonal antibodies (MoAbs) and immunoperoxidase methods were used to analyse the expression of HLA-DR molecules as well as phenotypic macrophage markers. P values apply to the differences between medians using the Mann-Whitney test. Median percentages of macrophages, lymphocytes and neutrophils were similar in all three groups. No differences were found in the median percentages of macrophages expressing the monocyte phenotype (MoAb UCHM1, CD14). However, in HIV-infected patients and transplant recipients a median of only 45% of macrophages expressed the pan-macrophage phenotype identified by MoAb EBM11 (CD68) in contrast with 98% in the normal volunteers. The AM population expressing the dendritic cell marker (MoAb RFD1) was also markedly reduced in both groups of immunocompromised patients (2 vs 28% in normal volunteers). Transplant recipients had significantly more phagocytic cells identified by MoAb RFD7 than the HIV-infected patients (25 vs 2%), but the numbers were still low when compared with the volunteers (48%). HLA-DR expression on BAL cells was reduced by 90% in both immunocompromised groups. For the transplant recipients, severity of pneumonitis was correlated with expression of dendritic cell marker RFD1, (Spearman's rank correlation r = 0.538, p less than 0.05) and pan-macrophage marker EBM11 (r = 0.581, p less than 0.05), while no such correlation was found in HIV-infected patients. These results suggest that a defective macrophage population is probably a serious factor contributing to immunosuppression.
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PMID:Alveolar macrophage populations are distorted in immunocompromised patients with pneumonitis. 135 52

Cytomegalovirus (CMV) infection in transplant patients is associated with an increased incidence of gram-negative pneumonia; the mechanism for this is unknown. Human alveolar macrophages (HAM) are an important part of the response of the lung to gram-negative bacteria. They interact with lipopolysaccharide (LPS) via the surface receptor CD14. The effect of CMV on CD14 expression by HAM was examined. HAM were obtained from normal volunteers by bronchoalveolar lavage, and some were exposed to CMV. CD14 expression was assessed by immunofluorescent microscopy and flow cytometry. CMV inhibited the surface expression of CD14 on HAM. Release of soluble CD14 was also reduced from infected cells, and Northern blot analysis revealed that CD14 mRNA was reduced in CMV-exposed cells. These findings were specific for CD14 expression. These results demonstrate that CMV inhibits the ability of HAM to express CD14.
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PMID:Cytomegalovirus inhibits CD14 expression on human alveolar macrophages. 865 15

Alveolar macrophages (AM), which represent the major resident population of immunocompetent cells in the lower respiratory tract, have been implicated in the pathogenesis of acute lung injury in view of their exceptional capacity to release a large array of inflammatory mediators. The ex vivo analysis of these cells, accessible to bronchoalveolar lavage (BAL) is hampered by the fact that, under conditions of respiratory failure, the AM pool is heavily expanded by polymorphonuclear neutrophils (PMN), which necessitates separation of these cell populations. In the present study, we describe a flow cytometric approach to sort human AM obtained from BAL samples of both healthy volunteers (n = 10) and patients with severe pneumonia demanding mechanical ventilation (n = 10), using forward scatter and high autofluorescence characteristics to discriminate AM from PMN and lymphocytes. This technique yielded highly purified AM populations (>95%) as evidenced by morphological analysis, cytochemistry, and CD71 and CD14 expression of the sorted cells. The flow sorting process, per se, did not induce the expression of the acute-phase cytokine tumor necrosis factor-alpha (TNF-alpha) in control AM as determined by reverse transcriptase-polymerase chain reaction. Unstimulated and lipopolysaccharide-induced TNF-alpha protein secretion were comparable in sorted and unsorted AM as demonstrated by enzyme-linked immunosorbent assay. We suggest flow sorting of viable human AM as an efficient and nonperturbing separation technique to yield highly purified cell populations especially from PMN-rich BAL fluids of critically ill patients.
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PMID:Separation of human alveolar macrophages by flow cytometry. 912 15

We report 2 cases of agranular CD2- CD4+ CD56+ non-Hodgkin lymphoma in which skin seemed to be the primary site. A 21-year-old woman's initial symptom was a skin nodule on the right cheek. She also had tumors in the nasopharynx, and the bone marrow subsequently became involved. No lymphadenopathy was present. She experienced complete remission after dose-intensified therapy with cyclophosphamide, hydroxydaunomycin, vincristine [Oncovin], and prednisone (CHOP), but the disease relapsed in the central nervous system 6 months later. An 81-year-old man experienced an 11-month history of skin nodules in the left forearm. On admission, he had a bone marrow infiltration of lymphoma cells. He died of pneumonia during chemotherapy. The malignant cells of the 2 patients had similar morphologic features, with a monocytoid nucleus and no cytoplasmic granules. The cells in both cases showed a unique phenotype: CD2-, CD3-, CD4+, CD8-, CD13-, CD14-, CD34-, CD16-, CD56+, CD57-, HLA-DR-positive. Staining for peroxidase and alpha-naphthyl butyrate esterase was negative. The T-cell receptor beta, gamma, delta, IgH, kappa, lambda genes were of germ line configurations. The DNA of Epstein-Barr virus was not detected from the bone marrow cells by polymerase chain reaction. Only 3 other cases with similar phenotypes have been reported; all had skin lesions. Although the origin of these cells remains unknown, we propose that this is a distinct clinicopathologic entity.
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PMID:A cutaneous agranular CD2- CD4+ CD56+ "lymphoma": report of two cases and review of the literature. 1043 11

Elevated levels of air pollution particulates < or = 10 microm in diameter (PM10) have been associated with an increase in mortality and morbidity due to pulmonary complications, including pneumonia. Impairment of inflammatory and host defense functions of the alveolar macrophage (AM) may be a precipitating factor. The present study was undertaken to determine whether human AM and blood derived monocytes (MO) modulate the expression of receptors important for phagocytosis of opsonized microbes (CD11b, CD11c), gram-negative bacteria (CD14), extracellular matrix interaction (CD29), and immune responses (CD11a, CD54, HLA-DR) when exposed to particulates obtained from urban air (UAP). Furthermore, phagocytosis of and oxidant generation by opsonized yeast were investigated in particle-exposed cells. AM and MO exposed to UAP for 18 h expressed significantly lower levels of CD11b and CD29. CD14 expression was markedly decreased in MO but not in AM, and CD11c was reduced in AM but not in MO. CD11a, CD54, and HLA-DR were unaltered in both phagocyte populations. Decreased receptor expression was not dependent on particle load in the cells. Phagocytosis of Saccharomyces cerevisiae and the chemiluminescence response were also significantly inhibited by UAP. Time-course studies revealed that decreased oxidant generation was evident already at 3 h postexposure, while significant effects on phagocytosis and CD11b expression were found at 18 h. These data indicate that exposure to particulate pollution is likely to impair host defense functions of AM and MO, which are important in elimination of a variety of pathogens in the lung.
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PMID:Decreased CD11b expression, phagocytosis, and oxidative burst in urban particulate pollution-exposed human monocytes and alveolar macrophages. 986 Mar 21

In the absence of a donor alternative a stem cell transplantation consisting of two cord blood components originating from the haploidentical brother was performed in a 2-year-old girl with c-ALL, early CNS relapse and 7% of blast cells in the BM 14 days before transplantation. Because of various ongoing infectious complications at that time, 1/8 of the immunogenetically acceptable sibling cord blood was ex vivo expanded 10 days before the transplantation date. The total CB consisting of 1.17 x 10(9) NC was cryopreserved in four separate bags. The one containing 1/8 of the total CB with 1.4 x 10(8) NC CliniMACS selected CD34+ cells was expanded in the presence of 100 ng/ml G-CSF, 100 ng/ml TPO and 100 ng/ml flt3-L in 10% autologous CB plasma and X-VIVO 10 medium at day -10 before transplantation. This expanded cell population was sterile and consisted of about 60% granulocytic cells (CD13+, CD15+), about 30% myelomonocytic cells (CD14, HLA-DR+), 5.2% megakaryocytes (CD61+) and 1.2% CD34+ cells. The proportion of T (CD3+), NK cells (CD56+) as well as dendritic cells (CD83+) was below 0.2%. The unseparated CB infused at day 0 and +1 consisted of a total of thawed 4.4 x 10(7) NC/kg BW, 5.8 x 10(4) CFU-GM/kg BW, 1.54 x 10(5) CD34+cells/kg BW and 7. 73 x 10(2) LTC-IC/kg BW. In addition, the 1 x 10(7) NC/kg BW ex vivo expanded cells representing 1.9 x 10(4) CFU-GM/kg BW, 1.13 x 10(5) CD34 cells/kg BW and 4.37 x 10(2) LTC-IC/kg BW, were infused at day +1. At day +2 after transplantation the patient revealed a focal pneumonia on X-ray with generalized sepsis and became catecholamine dependent. From day +4 the patient received 280 microg/m2 G-CSF. At day +5 she developed an erythroderma, which could not be identified as acute GVHD by biopsy. Early engraftment with leukocyte counts at days 8 and 14 were 350 and 700/microl, ANC 310 and 410/microl, respectively. Donor cells determined by chimerism analysis were 97% and 98% in the periphery at this early time. Most importantly, the pneumonia as well as the septicemia subsided within a few days. Notably, as well is the clearly shortened aplastic phase observed after this simultaneous CB cell component transplantation. The patients T cell and NK cell reconstitution could be detected at day +37 with 330 CD3+ cells/microl and 40 CD56+ cells/microl, respectively. The time to reach an absolute platelet count of 20 000 (50 000)/microl was 75 (103) days. The disease-free survival now exceeds 1 year in complete remission without chronic GVHD or any other health problems. These data show that the applicability of ex vivo expanded committed progenitors and LTC-IC, even in high risk leukemia at the time of transplantation, is feasible and can provide sufficient myeloid progenitors resulting in rapid engraftment able to clear bacterial pneumonia and sepsis. In addition, accelerated hematopoietic reconstitution apparently served as a well functioning platform for definitive graft-versus-leukemia activity. This transplantation of defined ex vivo generated components presents a feasible and generally applicable approach and may open a promising new avenue for cell therapy in malignant diseases.
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PMID:Simultaneous cord blood transplantation of ex vivo expanded together with non-expanded cells for high risk leukemia. 1046 29

Pneumocystis carinii is fungus which is a frequent cause of severe pneumonia in immunocompromised individuals. The P. carinii genome contains the PRT1 subtelomeric multigene family that encodes a kexin-like serine protease which is expressed on the surface of P. carinii. Analysis of the sequence of the carboxy-terminal sequence of many copies of PRT1 showed that they contained motifs characteristic of a glycosylphosphatidylinositol (GPI) anchor signal sequence. The ability of the C-terminal sequences of PRT1 to direct the addition of a GPI anchor was tested. CD14, a GPI-anchored monocyte glycoprotein antigen, was used as the basis of a heterologous system. CD14 was truncated to remove the carboxy-terminal sequences responsible for GPI-anchor addition. Addition of carboxy-terminal sequences from PRT1 restored high-level surface expression to the truncated CD14. Further, the majority of CD14-PRT1 recombinant protein was removed from the cell membrane by treatment with GPI-specific phospholipase C. These results suggest that the carboxy-terminal residues of most of the members of the PRT1 family of proteases have the potential to form a functional GPI-attachment signal.
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PMID:Functional glycosylphosphatidylinositol anchor signal sequences in the Pneumocystis carinii PRT1 protease family. 1169 52

Recent studies suggest that infection with Chlamydia pneumoniae is associated with atherosclerosis, and that cytokines play an important role in the initiation and progression of Chlamydia-induced inflammation. When freshly isolated peripheral blood mononuclear cells (PBMC) were stimulated for 24 h with sonicated C. pneumoniae, significant amounts of the pro-inflammatory cytokines TNF-alpha and IL-1beta and of the anti-inflammatory cytokine IL-10 were released into the supernatant. The addition of serum increased cytokine release induced by C. pneumonia two- to fivefold (p < 0.01). This effect was not due to complement, mannose-binding lectin (MBL) or lipopolysaccharide-binding protein (LBP). Incubation of PBMC with either anti-Toll-like receptor 4 (TLR4) or anti-CD14 blocking antibodies did not influence the production of cytokines induced by Chlamydia. The induction of cytokines by C. pneumoniae in macrophages from C3H / HeJ mice, known to have a defective TLR4, was identical to that measured in control macrophages from C3H / HeN mice. In contrast, incubation of PBMC with an anti-TLR2 blocking antibody significantly inhibited the production of TNF by 67 % and of IL-1beta by 72 %. In conclusion, C. pneumoniae stimulates cytokine production in a serum-dependent manner, but independently of complement, MBL and LBP. C. pneumoniae induces the pro-inflammatory cytokines TNF and IL-1beta through TLR2, but not TLR4 and CD14.
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PMID:Non-LPS components of Chlamydia pneumoniae stimulate cytokine production through Toll-like receptor 2-dependent pathways. 1193 27

The influence of LPS preincubation on hydrogen peroxide (H(2)O(2))-induced loss of epithelial barrier function was investigated in rat alveolar epithelial type II cells (ATII). Both apical and basolateral H(2)O(2) administration caused a manyfold increase in transepithelial [(3)H]mannitol passage. Apical but not basolateral preincubation of ATII with LPS did not influence control barrier properties but fully abrogated the H(2)O(2)-induced leakage response. The effect of apical LPS was CD14 dependent and was accompanied by a strong up-regulation of NO synthase II mRNA and protein and NO release. Inhibition of NO by N(G)-monomethyl-L-arginine suppressed the LPS effect, whereas it was reproduced by exogenous application of gaseous NO or NO donor agents. Manipulation of the glutathione homeostasis (buthionine-(S,R)-sulfoximine) and the cGMP pathway (1H-(1,2,4)oxadiazolo[4,3-alpha]quinoxaline-1-one; zaprinast) did not interfere with the protective effect of LPS. Superoxide (O*(-)(2)) generation by ATII cells was reduced by exogenous NO and LPS preincubation. O*(-)(2) scavenging with exogenous superoxide dismutase, the intracellular superoxide dismutase analog Mn(III)tetrakis(4-benzoic acid) porphyrin, and the superoxide scavenger nitroblue tetrazolium and, in particular, hydroxyl radical scavenging with hydroxyl radical scavenger 1,3-dimethyl-thiourea inhibited the H(2)O(2)-induced epithelial leakage response. In conclusion, apical but not basolateral LPS preincubation of ATII cells provides strong protection against H(2)O(2)-induced transepithelial leakage, attributable to an up-regulation of epithelial NO synthesis. It is suggested that the LPS-induced NO formation is effective via interaction with reactive oxygen species, including superoxide and hydroxyl radicals. The polarized epithelial response to LPS may be part of the lung innate immune system, activated by inhaled endotoxin or under conditions of pneumonia.
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PMID:Apical, but not basolateral, endotoxin preincubation protects alveolar epithelial cells against hydrogen peroxide-induced loss of barrier function: the role of nitric oxide synthesis. 1213 74

Endotoxin from Gram-negative bacteria bound to CD14 signals through Toll-like receptor (TLR) 4, while components of Gram-positive bacteria, fungi, and Mycobacterium tuberculosis (M.tb.) preferentially use TLR2 signaling. We asked whether TLR4 plays any role in host resistance to M.tb. infection in vivo. Therefore, we infected the TLR4 mutant C3H/HeJ mice and their controls, C3H/HeN mice, with M.tb. by aerosol. TLR4 mutant mice had a reduced capacity to eliminate mycobacteria from the lungs, spread the infection to spleen and liver, with 10-100 times higher CFU organ levels than the wild-type mice and succumbed within 5-7 mo, whereas most of the wild-type mice controlled infection and survived the duration of the experiment. The lungs of TLR4 mutant mice showed chronic pneumonia with increased neutrophil infiltration, reduced macrophages recruitment, and abundant acid-fast bacilli. Furthermore, the pulmonary expression of TNF-alpha, IL-12p40, and monocyte chemoattractant protein 1 was significantly lower in C3H/HeJ mice when compared with the wild-type controls. C3H/HeJ-derived macrophages infected in vitro with M.tb. produced lower levels of TNF-alpha. Finally, the purified mycobacterial glycolipid, phosphatidylinositol mannosides, induced signaling in both a TLR2- and TLR4-dependent manner, thus suggesting that recognition of phosphatidylinositol mannosides in vivo may influence the development of protective immunity. In summary, macrophage recruitment and the proinflammatory response to M.tb. are impaired in TLR4 mutant mice, resulting in chronic infection with impaired elimination of mycobacteria. Therefore, TLR4 signaling is required to mount a protective response during chronic M.tb. infection.
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PMID:Toll-like receptor 4 expression is required to control chronic Mycobacterium tuberculosis infection in mice. 1221 33


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