interleukin-8 and AIDS-Related-Opportunistic-Infections

This thesis is based on studies carried out during my appointment as a research fellow at the Department of Infectious Diseases, Hvidovre Hospital, University of Copenhagen, Denmark from 1993 to 1997. Part of this period was spent as a guest researcher at the Critical Care Medicine Department, National Institutes of Health, Bethesda, Maryland, USA. Pneumocystis carinii pneumonia (PCP) is the most frequent AIDS defining illness over the past 20 years. PCP is associated with considerable morbidity and mortality. An inflammatory reaction to P. carinii is believed to cause respiratory failure. This thesis has attempted to delineate important mechanisms of the inflammatory cascade, and to determine how inflammation is initiated during PCP. In histopathological studies of lung specimens it was shown that PCP caused significant inflammation and destruction of tissue. Specific pathological changes of the alveolar epithelium was observed in PCP but not for other HIV related lung diseases. By determining concentrations of soluble markers of immune activation we found that anti-microbial therapy exacerbated an ongoing inflammatory reaction. Adjuvant glucocorticosteroids suppressed levels of soluble immune markers. Bronchoalveolar lavage (BAL) neutrophilia has been associated with disease severity, and an increased risk of death from PCP. Through competitive inhibitory studies, we showed that BAL fluid neutrophil chemotactic activity largely was explained by the presence of interleukin-8 (IL-8). Further, we showed a correlation between high levels of BAL fluid IL-8 and mortality. Adjuvant treatment with glucocorticosteroids lowered BAL fluid IL-8 levels. In experimental studies we found that P. carinii Major Surface Antigen (MSG) induced IL-8 and tumor necrosis factor-alpha secretion from human monocytes and an alveolar epithelial cell line (A549). Binding of MSG to monocytes appeared to be mediated by mannose receptors, while A549 cells recognized MSG through mannose and glucan receptors. Glucocorticosteroids attenuated IL-8 secretion from A549 cells. These studies have confirmed that P. carinii infection induces tissue damage through a significant inflammatory response initiated by secretion of inflammatory mediators. Glucocorticosteroids attenuates the inflammatory response.

Topics: AIDS-Related Opportunistic Infections; Biomarkers; Humans; Hydro-Lyases; Interleukin-8; Pneumonia, Pneumocystis; Tumor Necrosis Factor-alpha

Cryptosporidium parvum can be regarded as a minimally invasive mucosal pathogen, since it invades surface epithelial cells that line the intestinal tract but does not invade deeper layers of the intestinal mucosa. Nonetheless, infection can be associated with diarrhea and marked mucosal inflammation. This article briefly reviews in vitro and in vivo models useful for studying the pathogenesis of C. parvum infection and explores the role of innate and acquired immune responses in host defense against this protozoan parasite.

Topics: AIDS-Related Opportunistic Infections; Animals; Antibody Formation; Cells, Cultured; Chemokine CXCL1; Chemokines, CXC; Chemotactic Factors; Cryptosporidiosis; Cryptosporidium parvum; Disease Models, Animal; Epithelial Cells; Growth Substances; Humans; Immunity, Cellular; Immunity, Innate; Intercellular Signaling Peptides and Proteins; Interferon-gamma; Interleukin-8; Intestines; Up-Regulation

Pneumocystis carinii pneumonia (PCP) may cause severe respiratory distress. This is believed to be partly caused by the accumulation of neutrophils in the lung. Interleukin-8 (IL-8) and leukotriene B4 (LTB4) are potent neutrophil chemo-attractants and activators. Eicosanoids [i.e. prostaglandins (PG) and leukotrienes (LT)] are pro-inflammatory mediators released from arachidonic acid by action of phospholipase A2 (PLA2) and have been implicated in the host response to micro-organisms. Bronchoalveolar lavage (BAL) was performed on patients with PCP as part of a randomized study of adjuvant corticosteroids vs. placebo, in addition to standard antimicrobial therapy. Re-bronchoscopy was offered at day 10. BAL fluid was available for 26 patients who had follow-up bronchoscopy performed. At diagnosis, IL-8 levels were elevated in patients with PCP, compared to healthy controls, and correlated with relative BAL neutrophilia and P(A-a)O2. LTB4 was also elevated in PCP, but failed to correlate with either BAL neutrophilia or P(A-a)O2. PLA2 activity in patients correlated with IL-8 levels and BAL neutrophilia, but not with P(A-a)O2. A trend towards a decrease in IL-8 levels in BAL fluid was detected in the corticosteroid-treated patients from days 0-10, whereas no change was detected in the placebo group. No change in levels of LTB4, LTC4, PGE2, PGF2a and PLA2 were detected cover time in either treatment group. This study establishes a correlation between IL-8, BAL neutrophilia and P(A-a)O2, and suggests a role of IL-8 as a mediator in the pathogenesis of PCP, whereas the role of eicosanoids seems less clear.

Topics: Adult; AIDS-Related Opportunistic Infections; Bronchoalveolar Lavage Fluid; Eicosanoids; Female; Humans; Interleukin-8; Lung; Male; Middle Aged; Neutrophils; Phospholipases A; Phospholipases A2; Pneumonia, Pneumocystis; Prednisolone

Opportunistic infections (OIs) are common among human immunodeficiency virus (HIV) patients; however, genetic susceptibility to these infections has not been studied. Recent studies have shown that interleukin-8 (IL-8) A/T genotype carriers are more susceptible to a variety of diseases. In this study, we showed the effects of IL-8 gene polymorphisms on OIs and symptoms such as sexually transmitted diseases (STDs), tuberculosis (TB), diarrhea, shortness of breath, weight loss, and viral load, in HIV and acquired immunodeficiency syndrome patients. Genomic DNA was purified from mouthwash samples collected from patients attending HIV centers in the Vhembe district. The IL-8 (-251) A/T locus was genotyped using allele-specific polymerase chain reaction followed by agarose gel electrophoresis. The results showed a weak association between the IL-8 AA genotype and OIs such as STDs (P = 0.143), diarrhea (P = 0.906), and TB (P = 0.762). Significant associations were found between the IL-8 AT genotype and weight loss (P = 0.019), shortness of breath (P = 0.043), and skin problems (P = 0.003). Low viral load was also found to be significantly associated with IL-8 AA genotype (P = 0.009). The present study suggests that different IL-8 genotypes are associated with resistance to various OIs. However, further studies using larger samples sizes are needed to confirm this hypothesis.

Topics: Adolescent; Adult; Aged; AIDS-Related Opportunistic Infections; Diarrhea; Female; Genetic Predisposition to Disease; Humans; Interleukin-8; Male; Middle Aged; Polymorphism, Single Nucleotide; Sexually Transmitted Diseases; South Africa; Tuberculosis; Viral Load; Young Adult

In a case-control study, we studied the effect of a single nucleotide polymorphism in the IL-8 promoter on the risk of the development of AIDS-related Kaposi's sarcoma (KS). KS developed in 46% of individuals with the TT genotype and in 66% of AA/AT genotypes (P=0.038). Patients with TT genotype were rarely affected with visceral KS (7% versus 36%; P=0.06), which suggests that carriers of the TT genotype are protected from (severe) KS development.

Topics: Acquired Immunodeficiency Syndrome; AIDS-Related Opportunistic Infections; Case-Control Studies; Genotype; Humans; Interleukin-8; Odds Ratio; Polymorphism, Genetic; Promoter Regions, Genetic; Risk Factors; Sarcoma, Kaposi

The expression of the two human interleukin (IL)-8 receptors, designated IL-8RA (CXCR-1) and IL-8RB (CXCR-2), on the surface of whole blood polymorphonuclear leukocytes (PMNL) was determined by use of receptor-specific monoclonal antibodies and flow cytometry. Sixteen subjects each were included in 4 study groups: healthy blood donors (ND), patients with pulmonary tuberculosis (TB), human immunodeficiency virus type 1-seropositive patients (HIV), and HIV-1-seropositive subjects with pulmonary tuberculosis (HIV/TB). A significant reduction in the percentage of PMNL expressing IL-8RA and IL-8RB and in their respective fluorescence intensities was found in TB, HIV, and HIV/TB groups compared with that obtained for the ND group. The greatest down-regulation of both receptors occurred in the HIV/TB group. Furthermore, associated with this reduced expression of IL-8 receptors was impairment of both intracellular calcium flux and migration of PMNL in response to IL-8 in a group of HIV/TB patients compared with that in healthy persons.

Topics: Adult; AIDS-Related Opportunistic Infections; Antibodies, Monoclonal; Antigens, CD; Antitubercular Agents; Calcium; CD4 Lymphocyte Count; Chemotaxis, Leukocyte; Female; Flow Cytometry; HIV-1; Humans; Interleukin-8; Lymphocytes; Male; Neutrophils; Receptors, Chemokine; Receptors, Interleukin; Receptors, Interleukin-8A; Receptors, Interleukin-8B; Tuberculosis, Pulmonary

Mycobacterium avium is one of the most prevalent opportunistic infections in AIDS patients, and neither prophylaxis nor treatment against M. avium is effective. To evaluate host defense mechanisms against mycobacterial infections, studies investigated whether neutrophils from AIDS patients could inhibit the growth of M. avium in vitro and what cytokines enhance neutrophil function against M. avium. Peripheral blood neutrophils from human immunodeficiency virus-negative and AIDS patients were incubated with media, granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), interleukin-8, or macrophage-inhibitory proteins and infected with M. avium, and the inhibition of bacterial growth was determined. G-CSF (1000 U/mL) and GM-CSF (2000 U/mL) stimulated neutrophils from AIDS patients to significantly inhibit M. avium growth. These results demonstrate that neutrophils from AIDS patients can respond to exogenously supplied G-CSF or GM-CSF by inhibiting the growth of M. avium.

Topics: Acquired Immunodeficiency Syndrome; Adult; AIDS-Related Opportunistic Infections; Blood Donors; Female; Granulocyte Colony-Stimulating Factor; Humans; Interleukin-8; Lipopolysaccharides; Macrophages; Male; Middle Aged; Mycobacterium avium; Neutrophils; Recombinant Proteins

Human herpesvirus 8 (HHV-8) is a recently discovered, virus that is highly associated with Kaposi's sarcoma (KS) and AIDS-associated body cavity lymphomas, although it is also found in some normal individuals. HHV-8 is related by nucleotide sequence homology to herpesvirus saimiri (HVS), which causes T cell lymphomas in some New World monkeys, and to Epstein-Barr virus (EBV), a human herpesvirus linked etiologically with Burkitt's lymphoma and nasopharyngeal carcinoma. We report that, like HVS but unlike EBV, HHV-8 contains a gene (ORF74) with significant sequence homology to the high-affinity IL-8 receptor, a member of the alpha (CXC) chemokine receptor family of transmembrane G protein-coupled receptors. We also show by reverse transcription PCR that the chemokine receptor-related HHV-8 gene is detectable in some RNA samples from KS tissue, and that its expression varies independently from that of ORF26, a minor capsid protein. The presence of a potential chemokine receptor in HHV-8 and its expression in KS tissue suggests that it may be important in the regulation of viral gene expression and may play a role in the etiology of KS and AIDS-related body cavity lymphomas.

Topics: AIDS-Related Opportunistic Infections; Amino Acid Sequence; Antigens, CD; Base Sequence; Capsid; DNA, Viral; Genes, Viral; Herpesvirus 8, Human; Humans; Interleukin-8; Molecular Sequence Data; Open Reading Frames; Receptors, Chemokine; Receptors, Cytokine; Receptors, Interleukin; Receptors, Interleukin-8A; Sarcoma, Kaposi; Sequence Homology, Amino Acid; Viral Proteins

Candidiasis is the most commonly encountered opportunistic infection among HIV-positive subjects. The purpose of this study was to assess specific keratinocyte immune parameters in the pseudomembranous and erythematous forms of HIV-associated oral candidiasis.. This collaborative study from three centers analyzed 25 HIV-positive and 10 HIV-negative subjects with either pseudomembranous or erythematous candidiasis. Oral biopsy specimens from lesional tissues were procured, and histopathologic features were correlated with immunohistochemical and in situ hybridization investigations for the expression of interleukin 1 alpha, interleukin 8, antimicrobial calprotectin, lymphocyte populations, and Candida antigen.. Both pseudomembranous and erythematous candidiasis among HIV-infected subjects showed a mild interface lymphocytic mucositis with the presence of neutrophilic subcorneal abscesses in the latter. Erythematous candidiasis cases that failed to show surface mycelia, did yield positive results for Candida antigens in the parakeratinized layer. The expression of inflammatory chemokines were positive in all groups and calprotectin appeared to serve as a keratinocyte barrier to hyphal penetration.. The erythematous form of candidiasis is often devoid of hyphae yet the presence of Candida antigens in the surface epithelium implicates an immune or allergic process. The intactness of chemokines and antimicrobial calprotectin in keratinocytes may explain why disseminated candidiasis is rarely encountered in HIV-infected patients.

Topics: AIDS-Related Opportunistic Infections; Antigens, Fungal; Antigens, Surface; Calcium-Binding Proteins; Candida; Candidiasis, Oral; Chemokines; Erythema; Gene Expression Regulation; Gene Expression Regulation, Fungal; HIV Seronegativity; HIV Seropositivity; Humans; Hypersensitivity; Immunohistochemistry; In Situ Hybridization; Interleukin-1; Interleukin-8; Keratinocytes; Leukocyte L1 Antigen Complex; Lymphocytes; Mouth Mucosa; Neural Cell Adhesion Molecules; Neutrophils; Stomatitis

Pneumocystis carinii pneumonia (PCP) is accompanied by an acute inflammatory infiltration of the lung parenchyma. The cellular infiltrate is characterized by inflammatory cells including neutrophils, lymphocytes and macrophages. Furthermore, neutrophilia in bronchoalveolar lavage (BAL) fluid has been shown to confer a poor prognosis in PCP. We therefore investigated the potential of BAL fluid from 17 patients with PCP to induce neutrophil chemotaxis. BAL fluid from patients induced considerable neutrophil chemotactic activity compared to normal controls. Elevated levels of IL-8 were detected in patient samples as compared to controls. A specific anti-IL-8 antibody significantly reduced chemotactic activity of patient samples by more than 50%. In conclusion, IL-8 appears to be a significant participant of neutrophil chemotaxis in AIDS-associated PCP, and may participate in the recruitment of neutrophils to the lung during PCP.

Topics: Adult; AIDS-Related Opportunistic Infections; Antibodies, Blocking; Bronchoalveolar Lavage Fluid; CD4 Lymphocyte Count; Chemotaxis; Humans; Interleukin-8; Leukotriene B4; Middle Aged; Neutrophils; Pneumonia, Pneumocystis; Recombinant Proteins

Cytokine levels were studied in the cerebrospinal fluid (CSF) of 16 adults with cryptococcal meningitis (CM). Low levels of tumor necrosis factor (TNF)-alpha and interferon-gamma, high levels of interleukin (IL)-1beta, IL-6, and IL-8, and the presence of IL-10 were documented. There were no significant differences in levels of TNF-alpha and interferon-gamma for CM and control patients. Mean CSF levels of IL-1beta (139.5 pg/mL), IL-6 (346 pg/mL), IL-8 (1160 pg/mL), and IL-10 (9.27 pg/mL) were significantly (P < .01) elevated in CM patients compared with levels in control patients. Despite the high CSF levels of IL-8, minimal leukocytosis was seen. Significant correlations between cryptococcal antigen titers and IL-10 levels (r = .8, P < .05), protein and cryptococcal antigen titer (r = .9, P < .05), and protein and IL-10 levels (r = .8, P < .05) were found.

Topics: Adult; AIDS-Related Opportunistic Infections; Cryptococcus neoformans; Cytokines; Humans; Interferon-gamma; Interleukin-8; Interleukins; Leukocytosis; Meningitis, Cryptococcal; Tumor Necrosis Factor-alpha

We evaluated the significance of interleukin-8 (IL-8) in Pneumocystis carinii pneumonia (PCP). Bronchoalveolar lavage (BAL) fluid and serum was prospectively collected in 76 consecutive HIV-infected patients with a primary episode of PCP, as well as in ten healthy control subjects. Patients were found to have elevated levels of IL-8 in BAL fluid compared to control subjects (p < 0.01). Nine patients died during the course of PCP. Non-survivors had significantly higher IL-8 levels in BAL fluid than survivors (p < 0.05). Furthermore patients with levels of IL-8 in BAL greater then 90 pg/ml (i.e. greater than control subjects) had significantly worse vital prognosis (log rank test, p < 0.05). Thirteen patients required mechanical ventilation (MV), and these patients had significantly elevated levels of IL-8 compared with patients not requiring MV (p < 0.05).. i) IL-8 in BAL fluid correlates to the clinical severity of the pneumonia, and ii) is a predictor of mortality and severe respiratory compromise.

Topics: Adult; AIDS-Related Opportunistic Infections; Bronchoalveolar Lavage Fluid; Denmark; Humans; Interleukin-8; Middle Aged; Pneumonia, Pneumocystis; Prognosis; Prospective Studies

Polymorphonuclear leukocytes (PMN) are the predominant inflammatory cells recruited in acute lung injury. This study compares the concentration of interleukin-8 (IL-8) to those of GRO alpha, both of which are CXC chemokines, in bronchoalveolar lavage fluid (BALF) in three acute pathologic states: bacterial pneumonia (BPN); adult respiratory distress syndrome (ARDS); and Pneumocystis carinii pneumonia (PCP). Levels of both IL-8 and GRO alpha were below 5 pg/ml in 16 nonsmoking volunteers who served as controls. Despite more than twice as many neutrophils in the BALF of the BPN group (n = 12) than in the group with ARDS (n = 13), both groups had similar levels of IL-8, of 569 +/- 120 pg/ml and 507 +/- 96 pg/ml, respectively. The GRO alpha concentrations in the BPN and ARDS patients were respectively 3.3 and 3.4 times those of IL-8, reaching 1,870 +/- 314 pg/ml for the BPN and 1,699 +/- 377 for the ARDS patients. In the PCP group (n = 48, 45 human immunodeficiency virus [HIV]-positive, 3 HIV-negative), GRO alpha levels (897 +/- 172 pg/ml) were sevenfold higher than IL-8 levels (123 +/- 40 pg/ml). In all pathologic states there was a good correlation between GRO alpha and IL-8 (r = 0.53, p = 0.0001). GRO alpha or IL-8 both correlate with the absolute neutrophil number/ml when all groups were studied together (r = 0.52, p = 0.0001). Only in the PCP and ARDS groups did IL-8 correlate with the PMN number.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Adolescent; Adult; AIDS-Related Opportunistic Infections; Bronchoalveolar Lavage Fluid; Bronchopneumonia; Chemokine CXCL1; Chemokines; Chemokines, CXC; Chemotactic Factors; Chemotaxis, Leukocyte; Growth Substances; HIV-1; Humans; Intercellular Signaling Peptides and Proteins; Interleukin-8; Male; Neutrophils; Pneumonia, Bacterial; Pneumonia, Pneumocystis; Respiratory Distress Syndrome; Statistics, Nonparametric

Interleukin-8 (IL-8) is a potent neutrophil chemoattractant and activator. Pneumocystis carinii pneumonia is associated with an accumulation of neutrophils in bronchoalveolar lavage (BAL) fluid. Thus, we hypothesized that IL-8 is involved in the pathogenesis of P. carinii pneumonia. BAL fluid and serum were prospectively collected in 76 consecutive HIV-infected patients with a primary episode of P. carinii pneumonia, as well as in 10 healthy control subjects. Patients were found to have elevated levels of IL-8 in BAL fluid compared with control subjects (p < 0.01). Nine patients died during the course of P. carinii pneumonia. Comparing survivors with nonsurvivors, the median IL-8 level in BAL fluid was 127 (0 to 3,900) versus 584 (127 to 6,100) pg/ml (p < 0.05). Furthermore, patients with levels of IL-8 in BAL fluid greater than 90 pg/ml (i.e., greater than control subjects) had significantly worse vital prognosis (log rank test, p < 0.05). Thirteen percent required mechanical ventilation (MV). Patients requiring MV had a median IL-8 level of 396 (25 to 6,100) versus 129 (0 to 3,900) pg/ml for patients not requiring MV (p < 0.05).. i) IL-8 in BAL fluid correlates to the clinical severity of the pneumonia, and ii) is a predictor of mortality and severe respiratory compromise.

Topics: Adult; AIDS-Related Opportunistic Infections; Biomarkers; Bronchoalveolar Lavage Fluid; Humans; Interleukin-8; Middle Aged; Pneumonia, Pneumocystis; Prognosis; Prospective Studies

Topics: AIDS-Related Opportunistic Infections; Bacterial Infections; Biomarkers; Bronchoalveolar Lavage Fluid; Enzyme-Linked Immunosorbent Assay; Granulocyte Colony-Stimulating Factor; Humans; Interleukin-8; Pneumonia; Pneumonia, Pneumocystis; Tuberculosis

To investigate the pathogenesis of lung injury in Pneumocystic carinii pneumonia and nonspecific interstitial pneumonitis (NIP), common pulmonary complications of human immunodeficiency virus (HIV) infection. The efficacy of corticosteroid therapy in P carinii pneumonia and the observation that bronchoalveolar lavage (BAL) neutrophilia predicts a poor prognosis support the premise that the lung injury of P carinii pneumonia is due to the host's inflammatory response to the infection.. In vitro measurements on previously collected BAL fluid samples.. The Clinical Center of the National Institutes of Health, a research hospital and tertiary care referral center.. Five normal volunteers, 5 asymptomatic HIV-positive patients, 10 HIV-positive patients with NIP (5 asymptomatic and 5 with respiratory symptoms), and 19 HIV-positive patients with P carinii pneumonia.. BAL leukotriene B4 (LTB4), interleukin 8 (IL-8), and phospholipase A2 (PLA2) were measured. IL-8 and PLA2 were elevated in patients with P carinii pneumonia, and IL-8 correlated with BAL fluid absolute neutrophil count. LTB4, IL-8, and PLA2 levels were elevated in patients with NIP; LTB4 and PLA2 levels correlated with absolute neutrophil count, and IL-8 correlated with alveolar-arterial oxygen pressure difference. IL-8 was elevated in the asymptomatic HIV-positive patients, and there was a trend toward elevation of PLA2 in this group.. IL-8 appears to play a role in the pathogenesis of lung injury in P carinii pneumonia and may be the principal neutrophil chemotaxin in this disease; PLA2 may also be involved in the pathogenesis of P carinii pneumonia. Both LTB4 and IL-8 may be involved in the recruitment of neutrophils and subsequent lung injury of NIP. These data suggest that there are varying mechanisms by which inflammatory cells are recruited to the lung in different HIV-related lung diseases.

Topics: Adult; AIDS-Related Opportunistic Infections; Bronchoalveolar Lavage Fluid; Chromatography, High Pressure Liquid; Female; HIV Infections; HIV Seropositivity; Humans; Interleukin-8; Leukotriene B4; Lung Diseases; Male; Middle Aged; Phospholipases A; Phospholipases A2; Pneumonia, Pneumocystis; Pulmonary Fibrosis