Expression of CD163 on peripheral blood monocytes in allergic asthma patients during specific immunotherapy (SIT)

Abstract

RATIONALE: CD163 is expressed on alternatively activated mononuclear phagocytes. The aim of this study was to evaluate the expression of CD163 and CD36 on peripheral blood monocytes of allergic asthma patients during SIT with house dust mite allergen extracts.METHODS: 25 mild allergic asthma (AA) patients with positive skin prick tests and a positive bronchial provocation test with Dermatophagoides pteronyssinus extract were selected for the study. 10 nonatopic healthy persons (HP) were used as a control group. SIT was performed on 20 (AA-IT) patients using Novo Helisen Depot. 5 patients (AA) who declined SIT were considered a control group. Blood was collected before, 3 months and 12 months after initiation of SIT. FACS analysis was performed on whole blood samples using labeled monoclonal antibodies against CD14, CD36 and CD163 (Pharmingen, USA).RESULTS: Before SIT more CD14 cells co-expressing CD163 (CD14+/CD163+) were found in AA-IT (47.4 +/- 19.6%) and AA (43.2 +/- 16%) than in HP (25.6 +/- 8.5; p< 0.01). In AA-IT patterns during SIT the number of CD14+/CD163+ cells increased reaching 54.8 +/- 11.6 % at 3 months and 49.1 +/- 8.9% at 12 months (p<0.01). The maximum increase in CD14+/CD163+ cells was associated with maximum improvement in FEV1. No change was found in the number of CD14+/CD163+ cells in AA during 12 month period. The number of CD14+/CD36+ monocytes decreased in AA-IT but did not change in AA.CONCLUSIONS: In house dust mite sensitive asthmatics, SIT is associated with alternative activation of peripheral blood monocytes. RATIONALE: CD163 is expressed on alternatively activated mononuclear phagocytes. The aim of this study was to evaluate the expression of CD163 and CD36 on peripheral blood monocytes of allergic asthma patients during SIT with house dust mite allergen extracts. METHODS: 25 mild allergic asthma (AA) patients with positive skin prick tests and a positive bronchial provocation test with Dermatophagoides pteronyssinus extract were selected for the study. 10 nonatopic healthy persons (HP) were used as a control group. SIT was performed on 20 (AA-IT) patients using Novo Helisen Depot. 5 patients (AA) who declined SIT were considered a control group. Blood was collected before, 3 months and 12 months after initiation of SIT. FACS analysis was performed on whole blood samples using labeled monoclonal antibodies against CD14, CD36 and CD163 (Pharmingen, USA). RESULTS: Before SIT more CD14 cells co-expressing CD163 (CD14+/CD163+) were found in AA-IT (47.4 +/- 19.6%) and AA (43.2 +/- 16%) than in HP (25.6 +/- 8.5; p< 0.01). In AA-IT patterns during SIT the number of CD14+/CD163+ cells increased reaching 54.8 +/- 11.6 % at 3 months and 49.1 +/- 8.9% at 12 months (p<0.01). The maximum increase in CD14+/CD163+ cells was associated with maximum improvement in FEV1. No change was found in the number of CD14+/CD163+ cells in AA during 12 month period. The number of CD14+/CD36+ monocytes decreased in AA-IT but did not change in AA. CONCLUSIONS: In house dust mite sensitive asthmatics, SIT is associated with alternative activation of peripheral blood monocytes.