Macrophages and Leydig Cells in Testicular Biopsies of Azoospermic Men
Figure 1
Semithin sections of the control testicular biopsy (obstructive azoospermia case, OA) (a) and biopsies from patients with nonobstructive azoospermia (NOA) ((b)–(d)). (a) Between several seminiferous tubules (St) with regular spermatogenesis, a part of the testicular interstitium with a cluster of Leydig cells (Lc) is visible. Leydig cells have a regular, round nucleus surrounded by an abundant cytoplasm. In the close proximity of these cells, a presumptive macrophage (↓) and several small blood vessels (bv) including capillaries (c) are noted (Lp, lamina propria; lsp, late spermatid; e, extravasated erythrocytes). (b) A part of testicular biopsy from a patient with NOA. Seminiferous tubules (St) are lined with Sertoli cells only and have a thickened lamina propria (Lp). Leydig cells (Lc) in the middle demonstrate a high vacuolisation of the cytoplasm. Presumptive macrophages (↓) are arranged at the periphery of seminiferous tubules or between Leydig cells. Several small blood vessels (bv) as well as capillaries (c) are also found. (c) Testicular biopsy from a patient with a spermatocyte “stop.” According to their location/related to seminiferous tubules (St) and blood vessels (bv)/, Leydig cells can be subdivided into peritubular (Pt) and perivascular (Pv). These cells demonstrate regular morphology, in contrast to many vacuolated Leydig cells (→) in the center (Lc) (Lp, lamina propria). (d) Testicular biopsy (NOA patient, spermatocyte “stop”) with Leydig cell hypertrophy/hyperplasia. Within the abundant population of Leydig cells, those with vacuolated cytoplasm (→) and large lipid droplets (encircled areas) can be observed (St, seminiferous tubules; M, presumptive macrophage; e, extravasated erythrocytes) (Toluidine blue, ×400/(a), (b)/, ×600/(c), (d)/, scale bar = 50 μm).
