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Prostaglandin (PG) E2 exerts its actions by acting on a group of G-protein-coupled receptors (GPCRs). There are four GPCRs responding to PGE2 designated subtypes EP1, EP2, EP3, and EP4 and multiple splicing isoforms of the subtype EP3. The EP subtypes exhibit differences in signal transduction, tissue localization, and expression regulation. Studies have identified that EP2 mediates many processes, such as facilitating ovulation and fertilization, suppressing dendritic cell differentiation, and promoting amyloid-β formation in Alzheimer’s disease.

Recombinant CHO-K1 cells stably overexpress human neonatal Fc receptor (FcRn) and beta-2 microglobulin (B2M). The existence of B2M enables the stable expression of FcRn. The surface expression of FcRn is validated by FACS analysis. This stable cell line product is designed for measuring binding affinity and stability of Fc region of antibodies, Fc fusion proteins, and antibody based biologics that binds with FcRn during biologics research and development.

Free fatty acid G protein coupled receptor family consists of four members and plays significant roles in nutrition regulation. GPR40 and GPR120 are activated by medium and long-chain FFAs, whereas GPR41 and GPR43 can be activated by short-chain FFAs. GPR40 is preferentially expressed in pancreatic beta-cells and mediates the majority of the effects of FFAs on insulin secretion. Researches show that GPR40 is a potential therapeutic target and plays an important role in the chain of events linking obesity and type2 diabetes.

FFA2 (GPR43) is a 330-amino acid G-protein coupled receptor that binds to fatty acid. FFA2 is highly selective expressed in leukocytes, which suggests a role in the recruitment of these cell populations toward sites of bacterial infection.

The formyl peptide receptors (FPR) are a class of G protein-coupled receptors involved in chemotaxis. FPR1 is a Gi-coupled GPCR. FPR1 is expressed in the vasculature, secretory epithelial cells, neurons and other tissues. FPR is involved in host defense against bacterial infection and in the clearance of damaged cells.

The FPR family members including FPR, formyl peptide receptor like-1 and -2 (FPRL1, FPRL2), are differently expressed in phagocytes with neutrophils expressing FPR and FPRL1 and monocytes/macrophages expressing all three. FPRL1 may constitute an additional molecular target for the development of therapeutic agents for Alzheimer’s disease (AD). GenScript has created a cell line that expresses FPRL1 in the CHO-K1 expressing Gα15.

Receptor activity-modifying proteins (RAMPs) are a class of protein which interact with and modulate the activities of several Class B G Protein-Coupled Receptors including the receptors for secretin, calcitonin (CT), glucagon, and vasoactive intestinal peptide (VIP).There are three distinct types of RAMPs, designated RAMP1, RAMP2, and RAMP3, each encoded by a separate gene.
Currently the function of RAMPs is divided into 2 class activities. Association of RAMPs with either the CT or CALCRL proteins forms 6 different receptors from the calcitonin receptor family. When associated with the Calcitonin receptor (CTR) or Calcitonin receptor-like (CALCRL) RAMPs can change the selectivity of the receptor for a specific hormone. In the cases of the other receptors mentioned however, there is no evidence that they can do this, but instead function to regulate trafficking of receptors from the ER / golgi to the membrane.
GenScript’s cloned human AMY3–expressing cell line is generated in the CHO-K1/Gα15 host.

The neuropeptide galanin elicits a range of biological effects by interacting with specific G-protein-coupled receptors. Galanin receptors are seven-transmembrane proteins that have been shown to activate a variety of intracellular second-messenger pathways. GALR1 inhibits adenylyl cyclase via a G protein of the Gi/Go family. GALR1 is widely expressed in the brain, spinal cord, and peripheral sites including small intestine and heart.

Actions of neuropeptide galanin are mediated by three G-protein coupled receptors, GalR1, GalR2, and GalR3. Human GALR2 was shown to couple to phospholipase C and to be involved in the elevation of intracellular calcium levels. GALR2 mRNA shows a wide distribution in the brain (mammillary nuclei, dentate gyrus, cingulate gyrus, posterior hypothalamic, supraoptic, and arcuate nuclei) and restricted peripheral tissue distribution with highest mRNA levels detected in human small intestine. Galanin has been implicated in anxiety-related behaviors, cognition, analgesia, and feeding in rodents.

Glucagon regulates blood glucose via control of hepatic glycogenolysis and gluconeogenesis and via regulation of insulin release from the β cell. Pharmacological administration of glucagon increases blood glucose in normal and diabetic subjects, and produces positive inotropic and chronotropic cardiovascular effects, relaxation of smooth muscle in the gastrointestinal tract and stimulation of growth hormone secretion. The actions of glucagon are mediated via a single adenylate cyclase-coupled glucagon receptor that also couples to the phospholipase C-inositol phosphate (PLC-IP) pathway leading to Ca²⁺ release from intracellular stores.

Ghrelin, a 28-amino-acid gut peptide is secreted from the stomach. It stimulates the release of growth hormone (GH) from the pituitary through GHS-R and plays important roles in energy homeostasis. In addition, ghrelin acts directly on the central nervous system to decrease sympathetic nerve activity. Ghrelin receptors (GHSRs) are concentrated in the hypothalamus-pituitary unit and may take the role of ghrelin in memory. GHSR is distributed in peripheral tissues, including the heart, lung, liver, kidney, pancreas, stomach, small and large intestines, adipose, and immune cells, suggesting that ghrelin has multiple functions in these tissues.

Gastric inhibitory polypeptide receptor (GIPR) is a Gs-coupled GPCR which is expressed in the pancreas, stomach, small intestine, adipose tissue, adrenal cortex, pituitary, heart, testis, endothelial cells, bone, trachea, spleen, thymus, lung, kidney, thyroid, and several regions in the CNS. Its ligand GIP is secreted after meal ingestion has been shown to stimulate bone formation resulting in lower occurrences of osteoporosis. GIPR may have therapeutic potential in the treatment of type 2 diabetes and obesity.

Tumor necrosis factor receptor superfamily member 18 (TNFRSF18) also known as activation-inducible TNFR family receptor (AITR) or glucocorticoid-induced TNFR-related protein (GITR) is a protein that in humans is encoded by the TNFRSF18 gene. GITR is currently of interest to immunologists as a co-stimulatory immune checkpoint molecule.

GLP1R binds specifically the glucagon-like peptide-1 (GLP1) and has much lower affinity for related peptides such as the gastric inhibitory polypeptide and glucagon. GLP1R is known to be expressed in pancreatic beta cells. Activated GLP1R stimulates the adenylyl cyclase pathway which results in increased insulin synthesis and release of insulin. Consequently, GLP1R has been suggested as a potential target for the treatment of diabetes. GLP1R is also expressed in the brain where it is involved in the control of appetite. Furthermore, mice which over express GLP1R display improved memory and learning.

The glucagon-like peptides include glucagon, GLP-1, and GLP-2 exert diverse actions on nutrient intake, gastrointestinal motility, islet hormone secretion, cell proliferation and apoptosis, as well as nutrient absorptionand assimilation. Glucagon-like peptide (GLP)-2, a product of the proglucagon gene, is expressed in enteroendocrine cells of the small and large intestine and is trophic to the gastrointestinal mucosa. GLP-2 also inhibits gastric acid secretion and emptying and up-regulates intestinal hexose transport. GLP-2 acts via binding to a single G protein-coupled GLP-2 receptor (GLP-2R).

The gonadotropin-releasing hormone receptor (GNRHR), also known as the luteinizing hormone releasing hormone receptor (LHRHR), is a member of the seven-transmembrane, G-protein coupled receptor (GPCR) family. It is expressed on the surface of pituitary gonadotrope cells as well as lymphocytes, breast, ovary, and prostate. Upon activation, the LHRHr stimulates tyrosine phosphatase and elicits the release of LH from the pituitary. Evidence exists showing the presence of LHRH and its receptor in extrapituitary tissues as well as a role in progression of some cancers.

The gene GPBRA1 encodes G protein-coupled bile acid receptor. Bile acid-binding induces its internalization, activation of extracellular signal-regulated kinase and intracellular cAMP production.

GPR103 is known as an orphan G protein-coupled receptor with reported expression in brain, heart, kidney, adrenal gland, retina, and testis. GPR103 mRNA has been reported to be highly expressed in the superficial layers of the entire spinal cord and a high density of 26RFa binding sites was observed in the superficial layers of the dorsal horn. QRFP binds and activates the human GPR103, as well as mouse GPR103A and GPR103B, with nanomolar affinities in transfected cells. Therefore, the current experiments investigated the effects of QRFP administration in rats and the effects of a high fat diet on prepro-QRFP mRNA and GPR103 receptor mRNA levels. 26RFa and QRFP are endogenous ligands of GPR103. An immunohistochemical study revealed that GPR103-like immunoreactivity (LI) was observed in the superficial layers of spinal dorsal horn, that QRFP-LI was observed in the dorsal root ganglion and that intrathecal 26RFa suppressed the expression of Fos-LI induced by paw formalin injection in the superficial layers of the spinal dorsal horn.

The GPR68 is a proton-sensing receptor involved in pH homeostasis. A study revealed that in osteosarcoma cells and primary human osteoblast precursors which expression of GPR68 exhibit strong PH-dependent inositol phosphate formation.

CHO-K1/Gqi5 is a CHO-K1 cell line stably expressing the chimeric Gqi5 alpha subunit protein which a chimeric Gq protein instead of the last five carboxyl-terminal amino acids from Gi. It is used as a host cell for transfection expression of Gi/o-coupled receptors, the constitutively expressed Gqi5 protein in the cells allows many transfected receptors which normally inhibit the cAMP pathway, to couple to Gq signal transduction and mobilize intracellular calcium. The cell line carries the hygromycin B resistance gene and is resistant to hygromycin B.

Recombinant CHO-K1 cells stably overexpress G15 alpha subunit protein (Gα15), which belongs to Gq/11/14/15 alpha subunit family. When Gα15 and Gs-coupled or Gi/o-coupled receptor are co-expressed in cells, the cells not only can be triggered to stimulate or inhibit the cAMP pathway based on the coupled G alpha subunit types, but also can conduct Gq-coupled signal transduction and mobilize intracellular calcium following certain ligand binding. This cell line is recommended to use as a host cell line for transient or stable expression of Gs and Gi/o -coupled receptors, which is able to provide more readouts to study G protein-coupled receptors.

Receptor activity-modifying proteins (RAMPs) are a class of protein which interact with and modulate the activities of several Class B G Protein-Coupled Receptors including the receptors for secretin, calcitonin (CT), glucagon, and vasoactive intestinal peptide (VIP).There are three distinct types of RAMPs, designated RAMP1, RAMP2, and RAMP3, each encoded by a separate gene.
Currently the function of RAMPs is divided into 2 class activities. Association of RAMPs with either the CT or CALCRL proteins forms 6 different receptors from the calcitonin receptor family. When associated with the Calcitonin receptor (CTR) or Calcitonin receptor-like (CALCRL), RAMPs can change the selectivity of the receptor for a specific hormone. In the cases of the other receptors mentioned however, there is no evidence that they can do this, but instead function to regulate trafficking of receptors from the ER / golgi to the membrane.
GenScript’s cloned human AMY1–expressing cell line is generated in the CHO-K1/Gα15 host.

Receptor activity-modifying proteins (RAMPs) are a class of protein which interact with and modulate the activities of several Class B G Protein-Coupled Receptors including the receptors for secretin, calcitonin (CT), glucagon, and vasoactive intestinal peptide (VIP).There are three distinct types of RAMPs, designated RAMP1, RAMP2, and RAMP3, each encoded by a separate gene.
Currently the function of RAMPs is divided into 2 class activities. Association of RAMPs with either the CT or CALCR proteins forms 6 different receptors from the calcitonin receptor family. When associated with the Calcitonin receptor (CTR) or Calcitonin receptor-like (CALCRL) RAMPs can change the selectivity of the receptor for a specific hormone. In the cases of the other receptors mentioned however, there is no evidence that they can do this, but instead function to regulate trafficking of receptors from the ER / golgi to the membrane.
GenScript’s cloned human AMY2 (RAMP2 + CALCR)–expressing cell line is generated in the CHO-K1/Gα15 host.

C-C chemokine receptor type 1 (CCR1) is a G protein-coupled receptor member of the CC chemokine subfamily of receptors. Following interaction with its specific chemokine ligands, like macrophage inflammatory protein 1 alpha (MIP-1 alpha), regulated on activation normal T expressed and secreted protein (RANTES), and monocyte chemoattractant protein 3 (MCP-3), it triggers the onset of a process known as chemotaxis. GenScript’s human CCR1-expressing stable subline is guaranteed to function properly in the calcium flux assay.

C-C chemokine receptor type 5 (CCR5) is a G protein-coupled receptor and a co-receptor for the entry of human immunodeficiency virus-1 (HIV-1) into cells. CCR5 chemokine receptor is involved in leucocytes chemotaxis to sites of inflammation and plays an important role in the macrophages, T cells, and monocytes recruitment. The chemokine ligands that bind to CCR5 are regulated on activation, normal T Cell expressed and secreted (RANTES) and macrophage inflammatory protein 1 alpha (MIP1α). GenScript’s human CCR5-expressing stable subline is guaranteed to function properly in the calcium flux assay.

Chemokine (C-X-C motif) receptor 1 (CXCR1) is a rhodopsin-like G protein-coupled receptor. It is one of two high-affinity receptors for the CXC chemokine interleukin-8 (IL-8), a major mediator of immune and inflammatory responses. The structure of human CXCR1 in a lipid bilayer should help to facilitate the discovery of new compounds that interact with GPCRs. GenScript’s human CXCR1-expressing stable subline is guaranteed to function properly in the calcium flux assay.

Chemokine (C-X-C motif) receptor 3 (CXCR3) belongs to the CXC chemokine receptor family. Similar to other chemokine receptors, it is a G protein-coupled receptor (GPCR). CXCR3 has two distinct splice variants, CXCR3A and CXCR3B, demonstrating different binding affinities. CXCR3-A binds to the CXC chemokines CXCL9 (MIG), CXCL10 (IP-10), and CXCL11 (ITAC) while CXCR3-B can also bind to CXCL4 in addition to CXCL9, CXCL10, and CXCL11. GenScript’s human CXCR3A-expressing stable subline is guaranteed to function properly in calcium flux assay.

Chemokine (C-X-C motif) receptor 5 (CXCR5) belongs to the CXC chemokine receptor family. CXCR5 plays crucial roles in B-cells migration into B-cell follicles of spleen and Peyer patches. CXCR5 reduces maintenance of immature neural cell populations and enhances proliferation of subgranular zone cells in the hippocampal dentate gyrus. GenScript’s human CCR1-expressing stable subline is guaranteed to function properly in the calcium flux assay.

Histamine is a ubiquitous messenger molecule released from mast cells, enterochromaffin-like cells, and neurons. Its various actions are mediated by histamine receptors H1, H2, H3, and H4. Specifically, the histamine receptor H2 belongs to the rhodopsin-like family of G protein-coupled receptors. As an integral membrane protein, it stimulates gastric acid secretion and regulates gastrointestinal motility and intestinal secretion and is thought to be involved in regulating cell growth and differentiation.

The histamine receptor H3 is a G_i-coupled GPCR expressed in the thalamus, caudate nucleus, putamen, cerebellum, amygdala, substantia nigra, hippocampus, hypothalamus and cerebral cortex. Activation of H3 receptor in human nasal mucosa inhibits sympathetic vasoconstriction. Expression of human H3 receptor splice variants in CHO cells shows that a deletion in the 2nd transmembrane domain alters ligand binding and deletions in the 3rd intracellular loop result in signal transduction being abolished.

Histamine receptor family consists of four members, namely, H1, H2, H3, and H4. The histamine H4 receptor is the most recently identified G protein-coupled histamine receptor that binds to several neuroactive drugs, including amitriptyline and clozapine. So far, H4 receptors have been found only on haematopoietic cells. This signifies its important role as a drug target for the treatment of inflammatory diseases.

Recombinant CHO-K1 cells stably overexpress human immunoglobulin gamma Fc region receptor II-a (FcγRIIa / CD32A 131His). The surface expression of CD32A 131His is validated by FACS analysis. This stable cell line product is designed for measuring binding affinity and stability of Fc region of antibodies and Fc fusion proteins, or antibody based biologics binding with CD32A 131His. GenScript also offers CD32A 131Arg stable cell line (Cat. No. M00887) for FcγRIIa polymorphism study.

Recombinant CHO-K1 cells stably overexpress Homo sapiens CD47 molecule (CD47) on the cell surface. The surface expression of CD47 is validated by FACS analysis. This cell line is recommended for cell-based binding assay to screening antibodies against CD47 or to measure binding affinity between CD47 and anti-CD47 antibodies.

This gene encodes a member of the TNF (tumor necrosis factor) receptor superfamily. The encoded protein functions in signal transduction pathways that activate inflammatory and inhibitory T-cell immune response. It binds herpes simplex virus (HSV) viral envelope glycoprotein D (gD), mediating its entry into cells. Alternative splicing results in multiple transcript variants

The protein encoded by this gene belongs to the CD28 and CTLA-4 cell-surface receptor family. ICOS (Inducible T-cell COStimulator) is expressed on activated T cells. It forms homodimers and plays an important role in cell-cell signaling, immune responses, and regulation of cell proliferation. It is thought to be important for Th2 cells in particular.

IP1 receptor is a receptor for prostaglandin I2 or prostacyclin. When binding with a prostacyclin molecule, the receptor changes conformation and activates Gs. Prostaglandin I2, the major product of cyclooxygenase in macrovascular endothelium, mediates a potent vasodilation and inhibition of platelet aggregation by binding to this receptor.

Integrin, alpha E (ITGAE) also known as CD103 (cluster of differentiation 103) is an integrin protein that in human. ITGAE is expressed widely on intraepithelial lymphocyte (IEL) T cells (both αβ T cells and γδ T cells) and on some peripheral regulatory T cells (Tregs). It has also been reported on lamina propria T cells. A subset of dendritic cells in the gut mucosa and mesenteric lymph nodes, known as CD103 dendritic cells, also expresses this marker.

Killer cell immunoglobulin-like receptors (KIRs) are transmembrane glycoproteins expressed by natural killer cells and are subsets of T cells. The KIR proteins are classified by the number of extracellular immunoglobulin domains (2D or 3D) and by whether they have a long (L) or short (S) cytoplasmic domain. KIR proteins with the long cytoplasmic domain transduce inhibitory signals upon ligand binding via an immune tyrosine-based inhibitory motif (ITIM), while KIR proteins with the short cytoplasmic domain lack the ITIM motif and instead associate with the TYRO protein tyrosine kinase binding protein to transduce activating signals. The ligands for several KIR proteins are subsets of HLA class I molecules; thus, KIR proteins are thought to play an important role in regulation of the immune response.

The KiSS1-derived peptide receptor (also known as GPR54 or the Kisspeptin receptor) is a G_q-coupled receptor which binds the peptide hormone kisspeptin (metastin). The KiSS1 gene inhibits metastatic activity of melanoma and other tumor cell lines, and clinical evidence supports a role for KiSS1 in inhibition of metastasis in human cancer. Kisspeptins and GPR54 also play a central role in hypothalamic regulation of puberty, by directly governing the release of gonadotropin-releasing hormone from the hypothalamus. In addition, mutations in GPR54 in mice and humans result in hypogonadotropic hypogonadism.

Lymphocyte-activation gene 3, also known as LAG-3, is a protein which in humans is encoded by the LAG3 gene.[1] LAG3, which was discovered in 1990[2] and was designated CD223 (cluster of differentiation 223) after the Seventh Human Leucocyte Differentiation Antigen Workshop in 2000[3]. LAG-3 is a cell surface molecule with diverse biologic effects on T cell function. It is an immune checkpoint receptor and as such is the target of various drug development programs by pharmaceutical companies seeking to develop new treatments for cancer and autoimmune disorders.

The dihydroxy-leukotriene, leukotriene B4 (LTB4) is a member of the G protein-coupled receptor (GPCR) family, in a subfamily of GPCRs that includes receptors for chemokines and other chemotactic factors. Recently, a second, lower affinity receptor for LTB4 (BLT2) has also been cloned, with broader ligand specificity for various eicosanoids. LTB4 stimulates neutrophil chemotaxis and secretion but may also affect immunomodulation, contraction of certain smooth muscles via an indirect mechanism and activation of the nuclear transcription factor PPARα (peroxisome proliferation activated receptor alpha). Chemotaxis, the principal effects of LTB4 and related dihydroxy-acids on leukocytes, occurs via activation of BLT1 receptors.

M1 was expressed in the CNS such as cerebral cortex, basal ganglia, limbic areas, vestibular system and esophageal smooth muscle. Synaptic transmission by muscarinic acetylcholine receptors (mAChRs) is employed throughout the central and peripheral nervous systems to elicit a large and diverse array of neurophysiological actions. An important aspect of mAChR functional diversity is reflected by the multitude of biochemical and electrophysiological actions evoked by acetylcholine binding to mAChRs, which include the regulation of intracellular levels of cAMP, cGMP and inositol phospholipids, and the opening or closing of the potassium, calcium, and chloride ion channels found in certain tissues.

Muscarinic acetylcholine receptors belong to a superfamily of seven-TM-domain receptors that interact with G-proteins to initiate intracellular responses. Five muscarinic receptor subtypes have been identified and named from M1 to M5. The M2 muscarinic receptor couples to G_i/o to inhibit cAMP production. GenScript co-transfected human M2 with Gα15 in the CHO-K1 which supports high levels of recombinant M2 expression on the cell surface and contains high levels of Gα15 to couple the receptor to the calcium signaling pathway.

Muscarinic acetylcholine receptors belong to a superfamily of seven-TM-domain receptors that interact with G-proteins to initiate intracellular responses. Five muscarinic receptor subtypes have been identified and named from M1 to M5. The M3 muscarinic receptors are located at many places in the body, e.g. smooth muscles, endocrine, exocrine glands, as well as lungs. They are also found in the CNS, where it induces emesis. They generally cause smooth muscle contraction and increased glandular secretions.

Muscarinic acetylcholine receptors belong to a superfamily of seven-TM-domain receptors that interact with G-proteins to initiate intracellular responses. Five muscarinic receptor subtypes have been identified and named from M1 to M5. The M4 muscarinic receptor couples to G_i/o to inhibit cAMP production. GenScript co-transfected human M4 with Gα15 in the CHO-K1 which supports high levels of recombinant M4 expression on the cell surface and contains high levels of Gα15 to couple the receptor to the calcium signaling pathway.

Muscarinic acetylcholine receptors belong to a superfamily of seven-TM-domain receptors that interact with G-proteins to initiate intracellular responses. Five muscarinic receptor subtypes have been identified, named M1 through M5. Receptors of the M5 receptor subtype couple through the G_q/11 class of G-proteins and activate the phospholipase C pathway. Activation of this pathway in turn leads to increases in free intracellular calcium levels as inositol triphosphate mediates release of calcium from the endoplasmic reticulum. RT-PCR reveals that M5 mRNA is quite uniformly expressed in brain. However, there is little data regarding the expression and function of the M5 receptor in peripheral tissues. Currently, it is clear that the M5 receptor, due to the high likelihood that its distribution is restricted to the CNS, probably plays a discrete role in dopaminergic transmission. Although the identification of M5 expression in salivary glands and iris-ciliary muscle suggests a broader role, the data on this is sparse and requires extensive confirmation.

The melanocortin receptor 2, MC2 receptor, is G_s-coupled GPCRs expressed in zona fasciculata of the adrenal cortex placental and stimulates production of cortisol. MC2 is a member of the rhodopsin family of 7-transmembrane and it’s also known as the ACTH receptor or corticotropin receptor because it is specific for ACTH alone. Activation of the MC2 receptor initiates a cascade of events affecting multiple steps in corticoid steroidogenesis. Mutations in MC2 may result in familial glucocorticoid deficiency, a group of autosomal recessive disorders characterized by resistance to ACTH.

The melanocortin receptor 3, MC3 receptor, is Gs-coupled GPCRs expressed in brain, placental, and gut tissues but not in melanoma cells or in the adrenal gland. MC3 receptor knockouts exhibit a metabolic syndrome. At 4-6 months old, MC3 receptor knockout mice show increased fat mass, reduced lean mass and a higher feed efficiency, with normal metabolic rates. MC3 receptor knockout mice are hyperleptinaemic and males are often mildly hyperinsulinaemic.

Human Recombinant CHO-K1/MC4/Gα15 (cAMP) Stable Cell Line stably overexpress the melanocortin 4 receptor gene (MC4). This stable cell line product is designed for measuring the In Vitro function of MC4.

The melanocortin receptor 5, MC5 receptor, is Gs-coupled GPCRs expressed in the adrenal gland, fat cells, kidney, leukocytes, lung, lymph node, mammary gland, ovary, pituitary, testis and uterus. Mice with targeted deletion of the MC5 receptor have a defect in water and thermoregulation secondary to their decreased production of sebaceous lipids.