Association of T Gamma Delta-CD16+ Cells and Anti-CMV Immunoglobulins in the Prevention of CMV Infection

Summary

CMV infection in transplantation remains the most frequent infectious complication causing increased morbidity and mortality. International recommendations advocate prevention of this infection by instituting direct antiviral treatment or monitoring viral replication by PCR with the start of curative antiviral treatment when the DNAemia is positive.

The risk of CMV infection varies according to the serostatus of the donor (D) and recipient (R) at the time of transplantation. In the absence of prophylaxis, CMV infection occurs in 60-80% of D+R-, 50-60% of D+R+ and 25-50% of D-R+.

The humoral anti-CMV response is represented by the production of antibodies to envelope proteins (gB and gH) and to molecules involved in viral attachment and entry into target cells. However, the majority of CMV-specific antibodies do not have antiviral neutralising activity. The investigators have identified a new player in the specific anti-CMV response expressing the Fc RIIIa receptor (CD16), that interacts with anti-CMV immunoglobulins (Ig): the Tgamma-delta V delta 2-negative lymphocyte (LTgdVd2neg). This lymphocyte subpopulation shows persistent expansion in the peripheral blood of kidney transplant patients with CMV infection. These cells express an effector-memory phenotype (CD45RA+/CD27-). This expansion is associated with resolution of infection in patients. The investigators have shown that CD16 is specifically and constitutively expressed on the surface of CMV-induced LTgdVd2neg in healthy volunteers and kidney transplant patients. The investigators have observed that one of the antiviral activities of anti-CMV IgG lies in its binding to the Fc RIIIa receptor (CD16) on the surface of LTgdVd2neg. The anti-CMV IgGs capturing virions thus activate CD16+ LTgdVd2neg with production of IFN interferon which in turn is responsible for inhibition of CMV viral multiplication.

Anti-CMV IgG is a recommended therapeutic option, with a marketing authorisation for the prevention of CMV infection in kidney transplantation in Europe and a Temporary Authorisation for Use in France.

Thus, R+ patients expressing a significant level of LTgdVd2neg CD16+ at D0 of transplantation could be protected against CMV, in the absence of direct antiviral treatment by the addition of anti-CMV Ig.

Conditions

• Kidney Transplantation
• CMV Infection

Interventions

DRUG

Cytotect

The inclusion visit is conducted by the investigating nephrologist and the patient will receive their first infusion of anti-CMV Ig. Patients with positive CMV serology at transplantation will receive 6 infusions of 100 units per kilogram of body weight every 15 days with the first injection on the day of transplantation, i.e. at visits D0, S2, S4, S6, S8 and S10. CMV infection will be monitored by quantitative PCR on whole blood every week during 3 months and then every 2 weeks until 4 months and then at months 5 and 6, 9 and 12.

Sponsors & Collaborators

• Biotest

  collaborator INDUSTRY

• University Hospital, Bordeaux

  lead OTHER

Study Design

Allocation

NA

Purpose

TREATMENT

Masking

NONE

Model

SINGLE_GROUP

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2021-11-17

Primary Completion

2024-12-19

Completion

2024-12-19

Countries

• France

Study Locations