Objective To investigated the relationship between nutritional status and PD-1/CTLA-4 in CAP patients to determine whether the nutritional status is associated with the immunosuppression generated by T cells.

Methods According the enrollment strategy, we enrolled 60 patients and collected their medical records.Take their blood samples and analyzed the distribution of PD-1 and CTLA-4 in different T cell subgroups.

Results The level of PD-1 and CTLA-4 in the CD4+, CD8+ and Tregs were inclusive with the SCAP occurrence, mortality and PSI score.The malnutrition risk group suffered higher percentage of SAP, longer hospital-stay days and higher mortality when compared with the no-risk group.The higher the PD-1/CTLA-4 levels were, the higher the NRS-2002 score was.

Conclusion A high NRS-2002 score may increase the length of hospital stay and the occurrence of SCAP. Higher PD-1 and CTLA-4 levels were associated with a higher PSI grade. Nutritional status influenced the occurrence of immunosuppression. Malnutrition status may increase the risk of immunosuppression, which is regulated by PD-1 and CTLA-4.

NO authors have competing interests

The author(s) received no specific funding for this work.

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According the International Ethical Guidelines for Biomedical Research Involving Human Subjects (2002) and Helsinki Declaration (2013), Ethics Committee of the Beijing Tsinghua Changgung Hospital approved this research and all patients were informed the consent and agreed to take part in the research.

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