Analysis of macrophage subtypes and annexin A1 expression in lesions of patients with cutaneous leishmaniasis.

Introduction: Cutaneous leishmaniasis is caused by protozoa of the genus Leishmania and transmission occurs through the bite of sandflies. It is an infectious disease, which affects skin and mucosa. The aim was to quantify the macrophages M1 and M2 and the annexin A1 expression in the skin lesions of patients with cutaneous leishmaniasis.

Methods: Skin biopsies from patients (n = 50) were analyzed and classified according to the lesion type as: exudative cellular reaction, exudative granulomatous reaction, exudative necrotic reaction, exudative necrotic-granulomatous reaction. Using the immunofluorescence technique, macrophages were identified by CD163 marker, differentiated by anti-MHCII and anti-CD206 antibodies, and annexin A1 expression was determined by arbitrary unit (a.u.) densitometry.

Results: In M1 macrophages, a greater expression of this protein was observed in the exudative cellular reaction type lesions (136.3 ± 2.6 a.u., assuming mean and standard derivation) when compared to the expression in the lesions of exudative granulomatous reaction, exudative necrotic reaction and exudative necrotic-granulomatous reaction patients (108.0 ± 2.3, 121.6 ± 3.2 and 124.7 ± 2.4 a.u., respectively). Regarding M2 macrophages, it was observed that patients with exudative cellular reaction lesion also had a higher expression of this protein (128.8 ± 2.6 a.u.), when compared to the expression in the lesions of exudative granulomatous reaction, exudative necrotic reaction and exudative necrotic-granulomatous reaction patients (105.6 ± 2, 113.9 ± 2.8, 114.3 ± 2.1 a.u., respectively).

Conclusions: These data suggest that annexin A1 is assisting macrophages in the phagocytosis process of patients with exudative cellular reaction lesion type.