Metabolic and functional changes in T helper cells during the periparturient period of dairy cows

Authors: FERNANDEZ WALLACE, T. - University Of Wisconsin; ARSHAD, U. - University Of Wisconsin; MANCHENO, M. - University Of Wisconsin; PRAISLER, G. - University Of Wisconsin; CID DE LA PAZ, M. - University Of Wisconsin; Kaplan, Bryan; SOSA, F. - University Of Wisconsin; PENAGARICANO, F. - University Of Wisconsin; Sacco, Randy; WHITE, H. - University Of Wisconsin; CANGIANO, L. - University Of Wisconsin

Submitted to: Journal of Dairy Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/15/2025
Publication Date: 12/16/2025
Citation: Fernandez Wallace, T., Arshad, U., Mancheno, M., Praisler, G., Cid De La Paz, M., Kaplan, B.S., Sosa, F., Penagaricano, F., Sacco, R.E., White, H.M., Cangiano, L.R. 2025. Metabolic and functional changes in T helper cells during the periparturient period of dairy cows. Journal of Dairy Science. 109(1):856-868. https://doi.org/10.3168/jds.2025-27307.
DOI: https://doi.org/10.3168/jds.2025-27307

Interpretive Summary: The periparturient period in dairy cows spans approximately 3 weeks before and 3 weeks after calving. It is a critical time during which the cow undergoes changes in bodily functions and processes such as energy utilization that leaves cows susceptible to numerous diseases and reproductive issues. The impact of these alterations of functions and processes on white blood cell subsets remains poorly understood. In this study, we used in vitro assays to determine the impact of changes in bodily functions and processes during the periparturient period on a specific white blood cell subset. Our results suggest that the cell responses are not suppressed, as had been assumed, but rather these cells may be overreactive, with enhanced inflammatory responses. The inflammatory responses may contribute to enhnaced disease susceptibilty seen in cows during this period.

Technical Abstract: The periparturient period in dairy cows is marked by major metabolic and physiological changes that increase disease susceptibility and immune dysfunction. However, the effect of those metabolic adaptations on the function of T helper (CD4') cells remains poorly understood. This study evaluated the in vitro metabolic function, proliferation capacity and phenotype of T helper cells across the periparturient period. Holstein cows (n = 17; 4.16 ± 1.34 lactations) were sampled at -28, +3, and +28 days relative to calving. Peripheral blood mononuclear cells were isolated and T helper cells were obtained using magnetic sorting. A Seahorse XF HS Mini Analyzer was used to assess the metabolic function through a T cell metabolic persistence assay, measuring glycolysis and oxidative phosphorylation via extracellular acidification and oxygen consumption rates, respectively. Cells were treated with assay medium (non-activated) or Phorbol 12-Myristate 13-Acetate and Ionomycin (activated) for the metabolic measurements. For proliferation capacity, cells were incubated with Concanavalin A for 72h and tracked using Cell Trace in Flow Cytometry. Cytokine production was measured in the cell culture supernatant using a MILLIPLEX Bovine Cytokine/Chemokine kit. Data was analyzed using a linear mixed effect model in R 4.4.3. T helper cells showed greater glycolytic and oxidative metabolism at +3 and +28 days. Expansion index was highest at +3 (-28 = 1.91, +3 = 2.65, +28 = 2.38 ± 0.19). Proinflammatory cytokine production, like IL-1a, IL-1ß and IL-6 also increased during +3 and +28 compared to -28. These findings suggest that T helper cell metabolism and proliferation capacity are upregulated after calving, and that these cells express a more pro-inflammatory phenotype, indicating that after parturition, immune function on this subset of cells does not appear to be suppressed, rather overreactive.