Tissue Resident CD8+T-cells as mediators of protective immunity in breastmilk transmission of HCMV.

While the role of breastmilk antibodies to protect infants from CMV has been investigated, the role of T-cells, have received little attention. We compared the frequency of memory T-cell populations in breastmilk between mothers of infants who acquired breastmilk HCMV (transmitters) and those with uninfected infants (non-transmitters). Non-transmitter moms had an increased frequency of CD8+ effector memory T-cells (Tem) in their breastmilk.

The tetraspanin CD151 marks a unique population of activated human T cells.

Tetraspanins are a family of proteins with an array of functions that are well studied in cancer biology, but their importance in immunology is underappreciated. Here we establish the tetraspanin CD151 as a unique marker of T-cell activation and, in extension, an indicator of elevated, systemic T-cell activity. Baseline CD151 expression found on a subset of T-cells was indicative of increased activation of the MAPK pathway.

Breast Milk Human Cytomegalovirus (CMV) Viral Load and the Establishment of Breast Milk CMV-pp65-Specific CD8 T Cells in Human CMV Infected Mothers.

The role of human cytomegalovirus (HCMV)-specific T-cell responses in breast milk of HCMV-seropositive mothers is not well defined. In these studies, we demonstrate that the frequency of cytomegalovirus (CMV)-pp65-specific T-cell responses in peripheral blood mononuclear cells (PBMCs) and breast milk cells (BMCs) is increased for CD8+ T cells in both sample sources when compared with CD4+ T cells. The frequency of pp55-specific CD8 T cells producing interferon γ (IFN-γ) alone or dual IFN-γ/granzyme rB producers is increased in breast milk compared with PBMCs.

Diminished CD103 (αEβ7) Expression on Resident T Cells from the Female Genital Tract of HIV-Positive Women.

Background: Tissue resident memory T cells (TrM) provide an enhanced response against infection at mucosal surfaces, yet their function has not been extensively studied in humans, including the female genital tract (FGT).

Methods: Using polychromatic flow cytometry, we studied TrM cells, defined as CD62L-CCR7-CD103CD69 CD4 and CD8 T cells in mucosa-derived T cells from healthy and HIV-positive women.

Results: We demonstrate that TrM are present in the FGT of healthy and HIV-positive women.