Parameters of T cell mediated immunity to commensal micro-organisms in patients with chronic purulent rhinosinusitis: a comparison between delayed type hypersensitivity skin test, lymphocyte transformation test and macrophage migration inhibition factor assay.

In 75 patients with unexplained chronic purulent rhinosinusitis T cell mediated immunity to three micro-organisms frequently colonizing the human upper respiratory tract, viz. Haemophilus influenzae, streptococci and Candida albicans, was assessed. Delayed type hypersensitivity (DTH) skin test reactivity was measured in vivo, whereas the blastogenic responsiveness (lymphocyte transformation test; LTT) and lymphokine production (e.g. migration inhibition factor; MIF) of the lymphocytes upon antigen stimulation were measured in vitro. MIF was assayed with a recently developed test system using the human monocytoid cell-line U937 as indicator cells in agarose microdroplets. Two-thirds of the 75 patients tested showed a defective DTH response to one or more of the microbial antigens; this contrasted to the findings in 25 healthy subjects, of whom over 90% showed a positive DTH reaction to any of the three antigens. PHA skin tests were entirely normal in both patients and healthy controls. Microbial antigen-specific LTT responses fluctuated considerably in time from strongly positive to negative and vice versa in healthy individuals as well as in patients. In general however, blastogenic responses in patients were comparable to or even higher than those of healthy persons. In the MIF assay, lymphocytes of all healthy individuals tested showed production of MIF upon stimulation with all three antigens; this again contrasted to two-thirds of the patients, whose lymphocytes showed a defective MIF production. Fluctuations of MIF-production in time could not be established and a very good correlation existed between the data obtained in the MIF assay and those of the DTH skin tests. These results indicate that apart from skin testing, the MIF assay seems to be the most suitable parameter to assess defects in T cell reactivity towards microbial antigens. These defects exist in two-thirds of our patients suffering from chronic purulent rhinosinusitis.

Abnormalities in cell-mediated immune functions to Haemophilus influenzae chronic purulent infections of the upper respiratory tract.

Delayed hypersensitivity (dh) skin test reactivity to a somatic antigen of Haemophilus influenzae was studied in 21 patients with unexplained, chronically relapsing, purulent upper respiratory tract infections. Only 2 showed a dh reactivity comparable to that of healthy controls. A majority--15 patients--had a defective dh response, whereas 4 showed exaggerated reactivity leading to necrosis of the test site and general feelings of malaise. Not only was the dh reactivity to somatic H. influenzae antigen affected, but also that to streptokinase/streptodornase and candidal antigen in most cases, though to a lesser extent. Skin test reactivity to the mitogen PHA was normal as were the dh skin test reactivities in 4 out of 5 control patients with mucous atopic rhinitis/sinusitis and 2 cases of nasal suppuration due to disturbed mucociliary transport. Delayed hypersensitivity skin test disorders were associated with elevated ratios of OKT4 + /OKT8 + peripheral lymphoid cells. In addition a high incidence of atopy and thyroid autoimmunity was evident in patients as well as in their first-degree relatives. A negative lymphocyte proliferative response to somatic H. influenzae antigen was found in 3 of our patients. These results suggest that unexplained, chronically relapsing upper respiratory tract infections might be based on restricted T-cell defects to H. influenzae, streptococcal, and candidal antigens. Such defects are reminiscent of the T-cell immune disorders to fungi playing a role in some cases of chronic mucocutaneous candidiasis.