Immunofluorescent characterization of lymphocytes in lungs of rats infected with Mycoplasma pulmonis

Abstract

Immunofluorescence was used to determine the relative percentages of T and B lymphocytes found in the lungs of normal and Mycoplasma pulmonis-infected F344 rats. Lymphocytes recovered from controls were approximately 25% T, 25% B, and 50% unclassified mononuclear cells. Infected animals had a 2.6-fold greater number of T cells and IgA-bearing cells, and a 1.6-fold greater number of unclassified mononuclear cells. These studies show that M. pulmonis infection significantly alters lung lymphocyte populations both quantitatively and in subpopulation distribution. Therefore, future studies of rat lung lymphocytes should utilize animals known to be free of this ubiquitous respiratory pathogen.

Murine respiratory mycoplasmosis in F344 and LEW rats: evolution of lesions and lung lymphoid cell populations

“…As described in other studies (13,21,22,26,36), including our own previous studies in rats (15), a significant number of cells morphologically indistinguishable from lymphocytes failed to stain with either T or B cell reagents. Furthermore, they failed to stain with anti-alveolar macrophage serum and were not adherent, phagocytic, or pinocytic.…”

“…Lymphoid cell recovery. Lung mononuclear cells were collected from each animal by a modification of the techniques of Hunninghake and Fauci (15,24) with the following isolation medium: RPMI 1640 medium (GIBCO, Grand Island, N.Y.) buffered to pH 7.3 with 25 mM HEPES (N-2-hydroxyethylpiperazine-N'-2ethanesulfonic acid; GIBCO) plus 1% L-glutamine (Difco Laboratories, Detroit, Mich.), 10%o fetal bovine serum (Difco), 100 U of penicillin G per ml, 5 mg of DNase (GIBCO) per liter, and 50 p.g of streptomycin per ml (15,24).…”

Vaccination of Lewis rats with temperature-sensitive mutants of Mycoplasma pulmonis: adoptive transfer of immunity by spleen cells but not by sera

“…Numerous cells infiltrate lungs of rats and mice following M. pulmonis infection (4,8,11). A significant number of cells (about 50% in tissue sections) were morphologically indistinguishable from lymphocytes, which failed to stain with either Tor B-cell reagents, and were called null cells.…”

T lymphocyte responses are critical determinants in the pathogenesis and resistance to mycoplasma respiratory disease

“…It is clear that lymphocyte recruitment and activation are important in the pathogenesis of mycoplasma respiratory disease, and T cells are an important component of these responses. As indicated earlier, a common characteristic of most animal and human mycoplasma disease is a slow, progressive increase in the number of organisms, accompanied by an accumulation of lymphoid cells consistent with chronic inflammation (3,61,93,94). In humans for example, M. pneumoniae infection is characterized by acute perivascular and peribronchial lymphoid infiltration resulting in destruction of respiratory epithelium (3,61).…”