Levels of interleukin-6 and interleukin-8 in seminal fluid of men attending an andrological clinic

Abstract

The presence of interleukins (IL) and other cytokines in seminal plasma was demonstrated in the literature. In particular, the levels of IL-6 were found to be related to male accessory gland inflammation. The close correlation to leucocyte count indicates a production of interleukins from the leucocytes and by the prostate gland. No relation of IL-6 levels to spermatogenic activity was quoted in the literature. We measured IL-6 and IL-8 in 454 men and compared the values with seminal parameters. The mean values of IL-6 30.7 +/- 101.2 pg ml-1 and IL-8 2023 +/- 1721 pg ml-1. The correlation analysis revealed a significant correlation of IL-6 and/or IL-8 to age, total fructose, immunoglobulin G (IgG) concentration and leucocyte count. The significant correlation of IL-6 and fructose levels indicates that also the seminal vesicles take part in the production of seminal IL-6. No correlation of the two interleukins measured to sperm parameters occurred. The calculation of a single harmonic trend revealed a significant trend over the year of the levels of IL-6 with a maximum in December and a peak-to-trough variation of 33% of the mean. It may be the consequence of a higher frequency of seminal tract inflammations in autumn and winter.

Semen characteristics and inflammatory mediators in infertile men with different clinical diagnoses

“…A clear association of pro inflammatory cytokines with seminal leukocytes has been reported by many authors (Eggert‐Kruse et al. , 2001; Friebe et al. , 2003; Kopa et al.…”

Paradoxical increase of sperm motility and seminal carnitine associated with moderate leukocytospermia in infertile patients

“…However, this regulation cannot explain the increased seminal carnitine levels observed in group C, which did not present an increased sperm count (see Tables 2 and 3). The presence of PMN granulocytes in the epididymal epithelium may promote carnitine uptake, and this migration of PMN granulocytes may be induced by interleukin 8, present at very high levels in seminal fluid in the case of leukocytospermia (47)(48)(49)(50). Activated polymorphonuclear granulocytes (see Table 1) could facilitate carnitine uptake by increasing the expression of OCTN2 (51) and the epididymal blood flow or by promoting angiogenesis (52).…”

Evaluation of Leukocyte Threshold Values in Semen to Detect Inflammation Involving Seminal Interleukin-6 and Interleukin-8

“…Studies performed to determine the seminal threshold value of IL-6 and IL-8 [13][14][15][16][17] have not resulted in a general consensus, which could be explained by differing patient populations and the use of various quantification methods for cytokines. Friebe et al, 20 for example, reported 30.7 and 2023 pg/mL as the mean values of seminal IL-6 and IL-8, respectively, in a study including 454 men, whereas IL-6 and IL-8 exhibited median concentrations of 1305 and 6 pg/mL, respectively, in a study by Politch et al 21 to establish reference values for immunologic factors in semen. Thus, because of the lack of consistency in studies concerning seminal cytokine levels, the 75th and 90th percentiles of IL-6 and IL-8 were defined as high and very high concentrations, respectively, to differentiate between inflammatory and noninflammatory semen.…”