Project description:Camelids are capable of producing both conventional tetrameric antibodies (Abs) and dimeric heavy-chain antibodies (HCAbs). While B cells generating these two types of Abs exhibit distinct B-cell receptors (BCRs), it remains unclear whether these two B cell populations differ in their phenotypes and developmental processes. Here, we collected eight PBMC samples before and after immunization from four Bactrian camels and conducted single-cell 5’ RNA sequencing. We characterized the functional subtypes and differentiation trajectories of circulating B cells in camels, including native B cells, memory B cells, intermediate B cells, atypical B cells, and plasma cells. Additionally, we reconstructed single-cell BCR sequences and revealed the IGHV and IGHC gene types. We found that B cells with variable genes of HACbs (VHH) were widely present in various functional subtypes and showed highly overlapping differentiation trajectories to B cells with variable genes of conventional Abs (VH). After immunization, the transcriptional changes in VHH+ and VH+ B cells were also largely consistent. Our study not only elucidates the cellular context of HCAb production in camels, but also lays the foundation for the development of single B cell-based nanobody screening.
Project description:The neck gland, an exclusive gland found in male camels, has been proven to secrete an amber-colored fluid and volatile substances during the mating season, exhibiting the capability to induce estrus in female camels. In this study, data-independent acquisition (DIA) proteomics was utilized to analyze differentially expressed proteins (DEPs) in the neck gland tissue of male Bactrian camels
Project description:The “ship of the desert”, the one-humped Arabian camel (Camelus dromedarius), has a remarkable capacity to survive in conditions of extreme heat without needing to drink water. One of the ways that this is achieved is through the actions of the antidiuretic hormone vasopressin (AVP) and the natriuretic hormone oxytocin (OXT), both of which are made in a specialised part of the brain called the hypothalamo-neurohypophyseal system (HNS), but exert their effects at the level of the kidney to, respectively, provoke water conservation and salt excretion. Interestingly, our electron microscopy studies have shown that the ultrastructure of the camel HNS changes according to season, suggesting that in the arid conditions of summer the dromedary’s HNS is in a state of permanent activation, in preparation for the likely prospect of water deprivation. Based on our camel genome sequence, we have carried out an RNAseq analysis of the camel HNS in summer and winter.
Project description:Bactrian camel (Camelus bactrianus) is a large, even-toed ungulate native to the desert areas of Central Asia. Aggregated lymphoid nodules area (ALNA) is known as the special anatomical structure of a Bactrian camel’s stomach that is found in the cardiac glandular area of the abomasum. To advance the exploration of the mucosal immune function of this anatomical feature within the gastrointestinal tract, we quantified the expressed proteins in ALNA using iTRAQ-based proteomic analysis in 6 Bactrian camels. In the experiment, we sampled the reticular mucosal folds region (RMFR) and longitudinal mucosal folds region (LMFR) separately from the ALNA and compared their proteomic quantification results with the samples from the Peyer’s patches (PPs).