# Proteomics and Microbiota Conjoint Analysis in the Nasal Mucus: Revelation of Differences in Immunological Function in Manis javanica and Manis pentadactyla

## TL;DR

This study compares the immune systems of two pangolin species using proteomics and microbiota analysis, revealing differences in their immunological functions.

## Contribution

The study reveals distinct immune mechanisms and microbiome profiles in two pangolin species, providing insights for immunotherapy.

## Key findings

- Manis pentadactyla has more pathogenic bacteria and uses a strong transferrin system to neutralize them.
- Manis javanica shows stronger anti-inflammatory ability, possibly due to a structural deficiency in C5a.
- The microbiome and immune factors differ significantly between the two pangolin species.

## Abstract

Pangolins, the only mammals covered in scales, play a crucial role in forest ecosystems as they specialize in myrmecophagy. Unfortunately, all eight pangolin species are critically endangered and susceptible to various pathogenic microorganisms, causing mass mortality, especially in captive Manis pentadactyla. However, information regarding the function of the immune system is lacking, which limits the development of effective rescue methods and subsequently hinders population rejuvenation. This study aimed to investigate the differences in the immunity of Manis javanica and Manis pentadactyla through proteomics and microbiotas conjoint analysis. Our findings revealed that Manis pentadactyla owned more pathogenic bacteria and neutralized through a powerful transferrin system. Manis javanica possessed stronger anti-inflammatory ability, which might be due to the structural deficiency of C5a. This study elucidates the distinct immune factors and microbiomes in Manis javanica compared to Manis pentadactyla, offering a foundational understanding for future immunotherapy research.

All eight pangolin species, especially captive Manis pentadactyla, are critically endangered and susceptible to various pathogenic microorganisms, causing mass mortality. They are involved in the complement system, iron transport system, and inflammatory factors. M. pentadactyla exhibited a higher abundance of opportunistic pathogens, Moraxella, which potentially evaded complement-mediated immune response by reducing C5 levels and counteracting detrimental effects through transferrin neutralization. In addition, we found that the major structure of C5a, an important inflammatory factor, was lacking in M. javanica. In brief, this study revealed the differences in immune factors and microbiome between M. javanica and M. pentadactyla, thus providing a theoretical basis for subsequent immunotherapy.