Related Experiment Video
Updated: Feb 12, 2026

Sperm Collection and Computer-Assisted Sperm Analysis in the Teleost Model Japanese Medaka Oryzias latipes
Published on: October 6, 2022
Evidence for the role of INSL3 on sperm production in boars by passive immunisation
I Minagawa1, Y Murata2, K Terada3
1Department of Applied Life Science, Faculty of Agriculture, Shizuoka University, Shizuoka, Japan.
Abstract:
Insulin-like factor 3 (INSL3), previously called relaxin-like factor, is essential for foetal testis descent and has been implicated in sperm production in adult males. This study investigated the role of INSL3 in sperm production by examining the effect of neutralising INSL3 by passive immunisation on testicular function and sperm output in boars. Six male Duroc boars were randomly assigned to passive immunisation and control groups (n = 3 each). The immunisation group was intravenously injected with an IgG fraction of anti-INSL3 antibody developed against the B domain of INSL3 at 2-week intervals from 21-40 weeks of age. The control group was treated with normal IgG in the same manner. Antibody administration reduced testis weight and caused a fourfold increase in the frequency of apoptotic germ cells, which was associated with upregulation of the pro-apoptotic caspase 3 and BAX, and downregulation of the anti-apoptotic XIAP and BCL2, and a substantial marked reduction in sperm concentration. Neutralising INSL3 delivered by passive immunisation reduced testis weight and sperm concentration by inducing germ cell apoptosis, suggesting that INSL3 acts as a germ cell survival/anti-apoptotic factor in the maintenance of sperm production.
Related Concept Videos
The Evidence for Evolution
Sperm Transport
The maturation phase occurs in the epididymis, where sperm...
Passive Filters
Low-Pass Filters
Low-pass filters are designed to transmit signals with frequencies lower than the cutoff frequency, ωc, and attenuate those above it. The cutoff...
Active versus Passive Immunity
Active Immunity
Active immunity refers to the resistance one develops...
Passive Diffusion: Overview and Kinetics
When administered orally, drugs establish a substantial concentration gradient between the gastrointestinal (GI) lumen and the bloodstream, expediting...
Sperm Structure and Semen Composition

