Abstract
Diffuse panbronchiolitis (DPB) is a chronic airway disorder first described by Homma, Yamanaka et al. in Japan (Naika 23: 442, 1969. Chest 83: 63, 1983.). Respiratory bronchioles are extensively damaged and severe respiratory functional impairment, especially the obstructive type, is seen. This disease belongs to a distinctively different category from other chronic obstructive pulmonary diseases or bronchiectasis.
Serum cold agglutinin (CA) titer has been reported to be frequently elevated with normal anti-Mycoplasma antibody titer (Hirata et al; Nikkyo 38: 90, 1978), and we investigated the serological character of CA in DPB.
1. Anti-Mycoplasma antibody titer was not elevated in any of the 10 cases.
2. CA titer was decreased when reacted with blood group 0 cord blood erythrocytes instead of adult red cells. CA titer was almost the same when papain-treated and neuraminidase-treated red blood cells were used. These results indicate that CA in DPB has anti-I specificity.
3. Results of the human milk inhibition test reported by Marsh et al. suggested that anti-IF (F=fetal) is more predominant than anti-ID (D=developed) in DPB.
4. CA elute was obtained by washing CA-bound red blood cells at a low temperature and tested by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Distinct bands were proved with anti-human μ and γ antisera. Indirect Coombs' tests using red blood cells sensitized by mercaptoethanol-treated CA sera and anti-human μ, γ, α, χ and λ. antisera, revealed that there were IgM, G and, in some cases, IgA fractions in CA, and that these CA were polyclonal.
5. The thermal amplitude of CA was tested at four diffurent temperatures; 4°C, 15°C, 25°C and 37°C. The CA titer greatly decreased when stored at a temperature above 15°C.
We concluded that CA in DPB is polyclonal, containing IgG and in some cases IgA as well as IgM, and has anti-I specificity. These results indicate that CA in DPB has similar characteristics with those found in cases of infections such as Mycoplasma infection.
