Related Experiment Video
Updated: Jun 28, 2026
12:36
Whole Ovary Immunofluorescence, Clearing, and Multiphoton Microscopy for Quantitative 3D Analysis of the Developing Ovarian Reserve in Mouse
Published on: September 3, 2021
Making themselves scarce: immune cells in the ovary
Bettina Toth1, Elisabeth Reiser2, Samuel M Vorbach3
1Department of Gynecological Endocrinology and Reproductive Medicine, Medical University of Innsbruck, Anichstraße 35, Innsbruck, 6020, Austria.
Journal of Ovarian Research
|June 26, 2026
Summary
Ovarian immune cells are scarce in young mice, with innate immune cells like macrophages and natural killer cells dominating. Adaptive immune cells, such as B and T cells, are mainly found in lymphoid organs like the spleen and lymph nodes.
Area of Science:
- Reproductive immunology
- Ovarian physiology
- Cellular immunology
Background:
- Oocyte survival requires interaction with stromal cells, but ovarian immune cell distribution is unclear.
- Understanding ovarian immune cell composition is crucial for reproductive health.
- Most reproductive potential is lost before puberty, highlighting the importance of early-life ovarian environment.
Purpose of the Study:
- To determine the distribution and composition of immune cells within the ovary.
- To compare ovarian immune cell populations with those in secondary lymphoid organs (spleen and lymph nodes).
- To elucidate the role of ovarian immune cells in reproductive potential.
Main Methods:
- Flow cytometry was used to analyze immune cell populations in six-week-old female C57BL/6 mice.
- Immune cells examined included macrophages, dendritic cells, natural killer (NK) cells, NKT cells, B cells, and T cells (CD4+ and CD8+).
- Analysis was performed on ovarian, splenic, and lymph node tissues.
Main Results:
- Immune cells constitute only 3% of ovarian cells in young mice.
- Ovarian immune cells are primarily composed of NK cells (24%), T cells (21%), macrophages (17%), and dendritic cells (7%).
- Spleen and lymph nodes show a higher proportion of adaptive immune cells, with B and T cells dominating (spleen: 56% B, 32% T; lymph nodes: 33% B, 62% T).
Conclusions:
- Ovarian immune microenvironment in young mice is characterized by a scarcity of immune cells, dominated by innate populations.
- Macrophages and natural killer cells are key innate immune cells in the ovary, aligning with their known roles in ovarian physiology.
- Adaptive immune cells (B and T lymphocytes) are predominantly found in secondary lymphoid organs, not the ovary.
More Related Videos
Related Concept Videos
02:07Oogenesis
In human women, oogenesis produces one mature egg cell or ovum for every precursor cell that enters meiosis. This process differs in two unique ways from the equivalent procedure of spermatogenesis in males. First, meiotic divisions during oogenesis are asymmetric, meaning that a large oocyte (containing most of the cytoplasm) and minor polar body are produced as a result of meiosis I, and again following meiosis II. Since only oocytes will go on to form embryos if fertilized, this unequal...
01:22Oogenesis
Oogenesis, the process of developing egg cells (female gametes), occurs within the ovaries and is fundamental to female fertility. This sequence begins during fetal development when diploid oogonia in the developing ovaries undergo mitotic divisions to produce primary oocytes. By birth, these primary oocytes enter prophase I of meiosis but become arrested in this stage, remaining suspended until puberty.
Each primary oocyte is surrounded by a layer of pre-granulosa cells, forming what is known...
Each primary oocyte is surrounded by a layer of pre-granulosa cells, forming what is known...
01:27Ovarian Cycle
The menstrual cycle includes a critical component known as the ovarian cycle, which undergoes two main phases each month—the follicular phase and the luteal phase. The follicular phase is variable and averaging around 14 days. Ovulation, triggered by a surge in luteinizing hormone (LH), marks the transition between the two phases. The second phase, the luteal phase, is relatively consistent, lasting approximately 14 days, and is marked by the activity of the corpus luteum. While a cycle length...
01:30Hormonal Control of the Ovarian Cycle
The ovarian cycle is meticulously regulated by the hypothalamic-pituitary-gonadal axis. This cycle orchestrates the release of a mature oocyte, essential for reproduction.
Before puberty, the hypothalamus releases GnRH in a low frequency, low amplitude pulsatile manner. This along with the immature hypothalamic-pituitary-gonadal axis activity, results in low estrogen levels and the absence of a fully functional ovarian cycle. At puberty, GnRH secretion increases in both frequency and...
Before puberty, the hypothalamus releases GnRH in a low frequency, low amplitude pulsatile manner. This along with the immature hypothalamic-pituitary-gonadal axis activity, results in low estrogen levels and the absence of a fully functional ovarian cycle. At puberty, GnRH secretion increases in both frequency and...
01:57Meiosis II
Meiosis II is the second and final stage of meiosis. It relies on the haploid cells produced during meiosis I, each of which contain only 23 chromosomes—one from each homologous initial pair. Importantly, each chromosome in these cells is composed of two joined copies, and when these cells enter meiosis II, the goal is to separate such sister chromatids using the same microtubule-based network employed in other division processes. The result of meiosis II is two haploid cells, each containing...
01:26Ovaries
The ovaries are roughly the size of almonds and measure approximately 2 to 3 centimeters in length. These paired structures are situated within the pelvic region and are anchored by the mesovarium—a peritoneal extension that also connects them to the wider structure of the broad ligament. The support system extends to the suspensory ligament, housing blood and lymphatic vessels. In addition, the ovarian ligament tethers the ovaries to the uterus.
On the ovarian surface, a layer of cuboidal...
On the ovarian surface, a layer of cuboidal...