Assessment of Natural Killer Cells in Unexplained Recurrent Pregnancy Loss

NCT ID: NCT03941470

Last Updated: 2019-05-08

Basic Information

• Recruitment Status: UNKNOWN
• Total Enrollment: 60 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2019-04-30
• Study Completion Date: 2020-07-20

Brief Summary

To assess natural killer cells frequency and activation in cases of unexplained recurrent abortion in comparison to fertile cases

• 2. . To study the expression of stimulatory receptors of natural killer cell.
• 3-To study the expression of inhibitory receptors of natural killer cell.

Detailed Description

NK-cell functioning is controlled by a wide range of receptors that are expressed on the cell surface. These receptors are either inhibitory or activating in nature. The family of inhibitory receptors consists of the killer immunoglobulin-like receptors (KIR) or Ig-like receptors (CD158), the C type lectin receptors (CD94-NKG2A) and leukocyte inhibitory receptors (LIR1, LAIR-1). Activating receptors are the natural cytotoxic receptors (NKp46, NKp44), C type lectin receptors (NKG2D, CD94-NKG2C), and Ig-like receptors (2B4). A particular NK cell typically expresses two to four inhibitory receptors in addition to an array of activation receptors. The killing by NK cells is mediated through several activating NK receptors. Among these are NKG2D and the three natural cytotoxicity receptors (NCRs), NKp30, NKp44, and NKp46 (Yang et al., 2000) Osne of the natural cytotoxicity receptors (NCRs) NKp46, , is a unique marker that functions in NK cell cytotoxicity and cytokine production. Expression of NKp46 on NK cells is lower in women with recurrent pregnancy loss, so evaluation of NKp46 on peripheral blood NK cells may provide a means of screening for reproductive abnormalities (Fukui et al., 2015).

During pregnancy, decidual NK cells comprise ∼70-80% of the decidual lymphocytes and are considered a special NK subset that does not exert cytolytic functions against trophoblast cells and has generally reduced cytotoxicity (Hanna and Mandelboim, 2007).

These cells express activating NK receptors, including all the NCRs and NKG2D. However, instead of triggering cytotoxicity, these receptors act to stimulate secretion of cytokines and angiogenic factors, which are essential for trophoblast invasion and vascular modifications (Hanna et al., 2006).

One study reported that pNK cell levels show changes in decidual NK cell levels (Park et al., 2010). Whereas some other reports have shown that the assessment of peripheral blood NK cells would not

Conditions

Female; Recurrent Miscarriage; Unexplained Pregnancy Loss

Study Design

• Observational Model Type: CASE_CONTROL
• Study Time Perspective: OTHER

Study Groups

unexplained recurrent pregnancy loss

peripheral blood sample examined by flowcytometry

No interventions assigned to this group

control fertile multipara

peripheral blood sample examined by flowcytometry

No interventions assigned to this group

Eligibility Criteria

Inclusion Criteria

• 1.Age less than 40 years. 2.History of two or more spontaneous miscarriages .

Exclusion Criteria

• 1. Age more than 35 years. 2. Women with elevated level of TSH above (2.5 mIU/ml) or prolactin above( 19.5 ng/mL)and uncontrolled DM.

3. Women with autoimmune disorder (antiphospholipid antibody syndrome)with LA1/LA2 ratio more than( 1.2).

4.Women receiving oral contraceptive pills.

• Maximum Eligible Age: 35 Years
• Eligible Sex: FEMALE
• Accepts Healthy Volunteers: No

Sponsors

Assiut University

OTHER

Sponsor Role: lead

Responsible Party

Yossra Mahmoud Mohammed

Assesment of Natu

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

assiut university

Role: PRINCIPAL_INVESTIGATOR

Assiut University

Locations

Yossra Mahmoud Mohammed

Asyut, , Egypt

Countries

Egypt

References

Fukui A, Kamoi M, Funamizu A, Fuchinoue K, Chiba H, Yokota M, Fukuhara R, Mizunuma H. NK cell abnormality and its treatment in women with reproductive failures such as recurrent pregnancy loss, implantation failures, preeclampsia, and pelvic endometriosis. Reprod Med Biol. 2015 Apr 11;14(4):151-157. doi: 10.1007/s12522-015-0207-7. eCollection 2015 Oct.

Reference Type: RESULT

PMID: 29259412 (View on PubMed)

Study Documents

Document Type: Study Protocol

View Document

Other Identifiers

17200339

Identifier Type: -

Identifier Source: org_study_id