Tissue eosinophil numbers and phospholipase B activity in mice infected with Trichinella spiralis

Eosinophil relationship in gut anaphylaxis during experimental ancylostomosis

Changes induced in the circulating and intestinal eosinophil levels and worm load were studied in female Swiss albino mice infected with multiple doses of Ancylostoma caninum larvae. There was a significant rise of both circulating and intestinal eosinophils in all the infected animals when compared with controls. In all the experimental groups of animals, peak eosinophilia was observed during the third week of post-infection and sustained upto 30th day with slight alterations. These studies indicated that eosinophilia will be induced due to anaphylactic reactions in the gut and eosinophilia in multiple infections is an anamnestic response.

Lysophospholipase activity of Ascaris suum-induced mouse peritoneal neutrophils and eosinophils

Lysophospholipase activity of mouse peritoneal neutrophils and eosinophils was studied to determine if neutrophils and eosinophils have lysophospholipase activity when treated with Ascaris suum whole worm extract, if zymosan activated complement can induce increased lysophospholipase activity, or if the immune status of the host has an effect on lysophospholipase activity. Neutrophils from noninfected or infected (immunized) mice were found to have increased lysophospholipase activity when treated with A. suum whole worm extract or zymosan activated complement demonstrating neutrophils as a source of lysophospholipase activity in the presence or absence of an immune response. Eosinophils from immunized mice had increased lysophospholipase activity when treated with either A. suum whole worm extract or zymosan activated complement.

Light and electron microscopic demonstration of phospholipase B activity in the mouse eosinophil

Phospholipase B (EC 3.1.1.5) which hydrolyzes phospholipids in the alpha and beta positions was demonstrated in murine leukocytes using light and electron microscopic histochemical techniques. Leukocytes (neutrophils, lymphocytes, macrophages, eosinophils) were harvested from peritoneal exudates of mice. Cells were fixed in 4% calcium-formol fixative for 10 min at 4 degrees C for light microscopy and 30 min at room temperature for electron microscopy, after which they were incubated at 37 degrees C in medium at pH 6.6 containing 2 microM lysolecithin and CaCl2. The fatty acids released during the hydrolytic reaction were trapped as a calcium precipitate and were converted to a cobalt precipitate for light microscopy by treatment with cobalt acetate or to a lead precipitate for electron microscopy by treatment with lead nitrate. The reaction products were observed to be present in eosinophils and absent in neutrophils, lymphocytes and macrophages. It is concluded that the eosinophilic leukocyte is the carrier cell for phospholipase B in inflammatory reactions.

Effect of anti-thymocyte serum on the eosinophil and lysophospholipase responses in mice infected with Trichinella spiralis

Anti-thymocyte serum (ATS) was administered to CD-1 mice infected with 100 Trichinella spiralis larvae and its effects on intestinal lysophospholipase (EC 3.1.1.5) activity, peripheral blood lymphocytes and bone marrow, peripheral blood and intestinal eosinophilia were assayed in the same experimental animal. The ATS caused a significant suppression of both the tissue lysophospholipase response and eosinophilia, in all three compartments, when compared to the values found in infected mice that were either treated with normal rabbit serum (NRS) or untreated. The suppressed eosinophil response and reduced lysophospholipase activity demonstrated a close temporal relation throughout the experiment. These findings support the hypothesis that helminth parasite-induced eosinophilia is the cause of increased lysophospholipase activity present in parasitized tissue and that the responses are thymus cell dependent.