The phrase "an endogenous source of" is correct and usable in written English.
It can be used in contexts discussing factors or elements that originate from within a system or organism, often in scientific or academic writing.
Example: "The study revealed that stress can act as an endogenous source of inflammation in the body."
Alternatives: "an internal source of" or "a native source of".
We examined the lineage-specific Wnt signaling activation, and identified that Rspo3 was specifically expressed in the fibroblast lineage, providing an endogenous source of the R-spondin to activate Wnt signaling.
Unlike endophthalmitis in adults, neonatal cases are overwhelmingly as a result of an endogenous source of infection.
WBCs thus represent an endogenous source of NO.
Additionally, intravenous administration of lentivirus causes infection of tissues known to be enriched in human immune cells, including the spleen and bone marrow[5], or which function as an endogenous source of IL-7, such as the liver[22].
Driver lines, expressing an endogenous source of integrase in the embryo from either nanos or vasa gene regulatory elements, were shown to double the transformation efficiency in D. melanogaster and removed the necessity to co-inject integrase mRNA [17].
PA imaging could potentially contribute since the RBCs are an endogenous source of strong contrast [ 29].
23 Strictly speaking, a female athlete is free to benefit from any endogenous source of androgen production.
The electron transport chain in the mitochondria is an important endogenous source of ROS.
It also shows that the skeleton can be an important endogenous source of lead exposure in environmentally exposed humans.
Although there has been a substantial decline in lead exposure in the United States during the past couple of decades (Pirkle et al. 1994), mobilization of existing lead stored in bone potentially represents an important endogenous source of exposure.
Since a previous study has shown that glutamate inhibits OPC proliferation in cell culture and that an undefined endogenous source of glutamate inhibits NG2 cell proliferation in developing cerebellum (Yuan et al., 1998), it is likely that glutamatergic synapses inhibit NG2 cell proliferation in an activity-dependent manner.
