Variations of macrophage inflammatory protein-1 alpha and 1-beta expression in the testis of rats undergoing autoimmune orchitis

GUAZZONE V.A.; RIVAL C.; DENDUCHIS B.; LUSTIG L.

Montreal, Canadá

Congreso; 12 International Congress of Immunology; 2004

International Union of Immunological Societes/Canadian Med. Assoc.

Experimental autoimmune orchitis (OAE) is characterized by an interstitial mononuclear cell infiltrate and a severe lesion of seminiferous tubules with germ cells undergoing apoptosis and sloughing. The aim of this work was to detect the variations in the expression of CC-chemokines (macrophage inflammatory protein (MIP)-1a and 1-b) and its receptors (CCR-5 and CCR-1) in the testis of rats undergoing autoimmune orchitis. EAO was induced in Sprague-Dawley adult rats by active immunization with an emulsion of testicular homogenate and complete Freund adyuvant using Bordetella pertussis as co-adjuvant (experimental (E) group). Control rats (C) were injected with saline and adjuvants. MIP-1a and -1b concentrations were determined in the conditioned medium obtained from cultures of testicular macrophages (MCM) of rats from C and E groups at different times after the first immunization (7, 30, 50 and 100 days (d)). An immunoperoxidase technique was performed on cryostat testis sections in order to obtain the number of CCR-1 and CCR-5 positive cells. We observed an increase of MIP-1a and -1b in the MCM of E rats killed at 7 and 30 d compared to the C group (E vs C: MIP-1a : 7d: 98.0±11.0 vs 56.8±13.4, 30d: 105.5±15.9 vs 32.6±6.6 (p<0.05); MIP-1b: 7d: 68.13±17.03 vs 73.6±14.3, 30d: 119.1±37.0 vs 47.5±15.3 (p<0.05) (pg/ml/104 cells)). An increase in the number of CCR-5+ macrophages was found in E rats compared to C rats (E vs C: 3.8±0.4 vs 0.9±0.2 (CCR-5+(x106)/testis) (p<0.0001)). No differences were found for CCR-1 among E and C groups. The increase of MIP-1a and MIP-1b production by testicular macrophages was observed in E rats before the testicular damage occurred. In contrast, MCP-1 (monocyte chemoattractant protein-1) increased in the MCM later on (50-100 d) and when the testis of E rats are damaged (Guazzone VA et al. J Reprod Immunol. 2003, 60(2):143-57). Temporal variation in the expression of chemokines in rats undergoing autoimmune orchitis suggests a selective role of MIP-1a, -b and MCP-1 in the recruitment of mononuclear cells to the testis.