title: Cellular and cytokine changes in the alveolar environment among immunocompromised patients during Pneumocystis jirovecii infection.
abstract: 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.
authors.affiliation: Service de Parasitologie Mycologie, Centre Hospitalier Universitaire de Toulouse, H ô pital Rangueil, Toulouse, France. xabierlete@yahoo.fr
authors.forename: Xavier
authors.initials: X
authors.lastname: Iriart
authors.forename: Benoit
authors.initials: B
authors.lastname: Witkowski
authors.forename: Caroline
authors.initials: C
authors.lastname: Courtais
authors.forename: Sarah
authors.initials: S
authors.lastname: Abbes
authors.forename: Jean
authors.initials: J
authors.lastname: Tkaczuk
authors.forename: Monique
authors.initials: M
authors.lastname: Courtade
authors.forename: Sophie
authors.initials: S
authors.lastname: Cassaing
authors.forename: Judith
authors.initials: J
authors.lastname: Fillaux
authors.forename: Antoine
authors.initials: A
authors.lastname: Blancher
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Magnaval
authors.forename: Bernard
authors.initials: B
authors.lastname: Pipy
authors.forename: Antoine
authors.initials: A
authors.lastname: Berry
mesh_terms: D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry / Q000166:cytology; D018791:CD4 Lymphocyte Count; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D016207:Cytokines / Q000378:metabolism*; D005260:Female; D006801:Humans; D007111:Immunity, Cellular; D016867:Immunocompromised Host; D016676:Macrophages, Alveolar / Q000276:immunology; D008297:Male; D008875:Middle Aged; D045363:Pneumocystis carinii / Q000276:immunology / Q000472:pathogenicity*; D011020:Pneumonia, Pneumocystis / Q000276:immunology / Q000473:pathology*; D011650:Pulmonary Alveoli / Q000276:immunology / Q000382:microbiology / Q000473:pathology*
chemical_list: D016207:Cytokines