PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Hypersensitivity, Delayed”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 703 records · Page 39Linked to original sources

Comparison of murine delayed hypersensitivity reactions elicited with particle-associated versus soluble human gamma-globulin.

Footpad reactions elicited in DHS mice using human gamma-globulin (HGG)-coated polystyrene latex particles and soluble HGG (sHGG) were compared. Both the magnitude and the persistence of DHS lesions produced by HGG-latex were considerably greater; at 24, 48 and 72 h after challenge, the level of reactivity induced by HGG-latex was 24, 41 and 71% higher, respectively, than those elicited with sHGG. Early nonspecific swelling following injection of HGG-latex in footpads of normal mice was negligible by 24 h, whereas Arthus-responsive animals did not return to control levels until 48 h. The possible advantages and limitations of using particle-associated protein to elicit DHS reactions are discussed.

Animals↗

Delayed hypersensitivity reactions in rats and their response to clinical dextran.

Four colonies of rats were tested for their ability to produce adjuvant-induced arthritis, oxazolone contact hypersensitivity and the dextran anaphylactoid reaction. Tuck Wistar and Hooded Lister rats, both of which respond to dextran, showed disseminated inflammatory lesions after adjuvant and exhibited oxazolone sensitisation, regardless of the age of the animal. Spontaneously hypertensive rats, which at all ages respond to dextran, also responded to adjuvant and oxazolone but only when they were young; as they grew older, this response to these two agents diminished. Wistar NELP rats, which at all ages do not respond to dextran, responded to oxazolone; sensitivity to adjuvant, however, was maximal only in young animals. The link between the ability of rats to resist the dextran anaphylactoid reaction and their failure to respond to adjuvant with disseminated inflammatory lesions has not been confirmed.

Anaphylaxis↗

Delayed hypersensitivity and HLA in smear-positive pulmonary tuberculosis.

Tuberculin responses were quantified by induration of the skin, velocity of blood flow in dermal microcirculation and composition of the cellular infiltrate in 125 patients with tuberculosis and 39 healty controls. The diameters of the tuberculin responses were greater in HLA-DR15-positive patients than in DR15-negative patients. The density of infiltrating CD(4+)-positive cells showed a positive correlation with induration in DR15-negative subjects (r = 0.54). A fraction of DR15-positive patients gave large tuberculin responses (> or = 15 mm) but with few CD4+ cells in the test site (< 500/mm2); these patients had a greater percentage of cells in the diffuse dermal infiltrate than in the perivascular region, greater blood flow velocities in the tuberculin response but more frequently with central relative slowing of blood flow and had higher total IgG and specific antimycobacterial antibody levels compared to other DR15-positive patients. If the inflammatory infiltrate in the lungs parallels that in the tuberculin skin test, the lack of immunocompetent cells and tissue hypoxia could permit pulmonary cavitation and explain the association of HLA-DR15 with smear-positive pulmonary tuberculosis.

Blood Flow Velocity↗