Mus musculus strain:C57BL/6 Raw sequence reads. Mus musculus strain:C57BL/6

Intestinal nematodes suppress immune responses in the context of vaccination, allergy and secondary infection. The mechanisms proposed for this suppression is attributed to the dominance of Type 2 cell and induction of systemic Treg immune response.In this research, we show that chronic nematode infection leads to impaired peripheral responses to vaccination due to a generalized reduction in the responsive lymphocyte pool.We observed that skin-draining lymph nodes (LNs) in mice that are chronically infected with the intestinal nematode Heligmosomides polygyrus, do not reach the same cellularity as worm-free mice upon subsequent BCG infection in the skin. Importantly, B cells and T cells, all declined in skin-draining LN of H. polygyrus-infected mice, resulting in LNs atrophy and altered lymphocyte composition. Importantly, anti-helminthic treatment improved lymphocyte numbers in skin-draining LN, indicating that time after deworming is critical to regain full-scale LN cellularity.Thus, our findings show that chronic nematode infection leads to a paucity of lymphocytes in peripheral lymph nodes, which acts to reduce the efficacy of immune responses at these sites.