Immune Cell Populations in Idiopathic Recurrent Pregnancy Loss and Unexplained Infertility in Venezuelan Admixed Women

Unexplained infertility and idiopathic recurrent pregnancy loss (RPL) have a prevalence of 1–5% of women of reproductive age in different populations. There are a few reports comparing the circulating immune cell populations and subpopulations in these medical entities in admixed populations. The study aimed to assess the different leukocyte, mononuclear cell populations, and T lymphocyte subpopulations and HLADR expression, as a marker of activation, in an admixed group of Venezuelan women: 80 controls, 73 women with RPL (53 primary, 20 secondary), and 26 infertile (20 primary, six secondary). Endometriosis was clinically ruled out in all patients and controls. Total leukocytes were 10–12% higher (p < 0.0001) in the infertile group, while neutrophils were 11% in the infertility group (p < 0.0001). In contrast, lymphocytes, CD3CD4 cells, NK cells, and HLADR+ cells were elevated (10–15, 18–22, 50–60, and 700–800% increase, respectively) in all patient groups. Changes in B cell numbers and monocyte counts were also observed. HLADR expression was significantly increased (p < 0.0001) in T cells, CD56+ cells, and monocytes of all patients. In infertile patients, a correlation was recorded between HLADR and T memory cells. Marked differences in peripheral blood leukocytes, NK cells, monocytes, T-cell populations, and HLADR suggest a proinflammatory effect. HLADR can be used as a simple biomarker to monitor pharmacological treatment in these patients.