Novel Antibody Exerts Antitumor Effect through Downregulation of CD147 and Activation of Multiple Stress Signals.

CD147 is an immunoglobulin-like receptor that is highly expressed in various cancers and involved in the growth, metastasis, and activation of inflammatory pathways via interactions with various functional molecules, such as integrins, CD44, and monocarboxylate transporters. Through screening of CD147-targeting antibodies with antitumor efficacy, we discovered a novel rat monoclonal antibody #147D. This humanized IgG4-formatted antibody, h4#147D, showed potent antitumor efficacy in xenograft mouse models harboring the human PDAC cell line MIA PaCa-2, HCC cell line Hep G2, and CML cell line KU812, which featured low sensitivity to the corresponding standard-of-care drugs (gemcitabine, sorafenib, and imatinib, respectively). An analysis of tumor cells derived from MIA PaCa-2 xenograft mice treated with h4#147D revealed that cell surface expression of CD147 and its binding partners, including CD44 and integrin α3ß1/α6ß1, was significantly reduced by h4#147D. Inhibition of focal adhesion kinase (FAK), activation of multiple stress responsible signal proteins such as c-JunN-terminal kinase (JNK) and mitogen-activated protein kinase p38 (p38MAPK), and expression of SMAD4, as well as activation of caspase-3 were obviously observed in the tumor cells, suggesting that h4#147D induced tumor shrinkage by inducing multiple stress responsible signals. These results suggest that the anti-CD147 antibody h4#147D offers promise as a new antibody drug candidate.

Subcellular distribution of α2-adrenoceptor subtypes in the rodent kidney.

Renal α2-adrenoceptors have been reported to play a role in the regulation of urinary output, renin secretion, and water and sodium excretion in the kidneys. However, the distribution of α2-adrenoceptor subtypes in the kidneys remains unclear. In this study, we aimed to investigate the localization of α2-adrenoceptor subtypes in rat kidneys using 8-week-old Sprague-Dawley rats. Immunofluorescence imaging revealed that both α2A- and α2B-adrenoceptors were expressed in the basolateral, but not apical, membrane of the epithelial cells of the proximal tubules. We also found that α2A- and α2B-adrenoceptors were not expressed in the glomeruli, collecting ducts, or the descending limb of the loop of Henle and vasa recta. In contrast, α2C-adrenoceptors were found to be localized in the glomeruli and lumen of the cortical and medullary collecting ducts. These results suggest that noradrenaline may act on the basement membrane of the proximal tubules through α2A- and α2B-adrenoceptors. Moreover, noradrenaline may be involved in the regulation of glomerular filtration and proteinuria through the induction of morphological changes in mesangial cells and podocytes via α2C-adrenoceptors. In the collecting ducts, urinary noradrenaline may regulate morphological changes of the microvilli through α2C-adrenoceptors. Our findings provide an immunohistochemical basis for understanding the cellular targets of α2-adrenergic regulation in the kidneys. This may be used to devise therapeutic strategies targeting α2-adrenoceptors.

Symmetrical Skin Lesions on the Gluteal Region in a Patient with Anti-Laminin-332 Mucous Membrane Pemphigoid.

Mucous membrane pemphigoid (MMP), previously called cicatricial pemphigoid, is a rare subepidermal immunobullous disorder that primarily affects the mucous membranes (1,2). MMP is divided into two major subtypes, anti-BP180-type MMP and anti-laminin-332 (previously called laminin 5 or epiligrin) MMP. Anti-laminin-332 MMP is known to be associated with malignant tumors (3), which may cause overexpression of autoantibodies and induce autoimmunity to laminin-332 (4). MMP primarily affects the mucous membranes, and widespread skin lesions are rare. In MMP, circumscribed skin lesions have been previously reported as occurring on the head, neck, and upper trunk (5). We report a case of anti-laminin-332 MMP presenting with symmetrical skin lesions characteristic of MMP on the weight-bearing areas of the gluteal region. A 66-year-old Japanese man presented with a month-long history of multiple erosions and blisters on the mucous membranes and skin, with conjunctival hyperemia, nasal obstruction, oral pain, and hoarseness of voice. Three days before the first visit, he was diagnosed with gastric cancer with liver metastasis by gastrointestinal endoscopy and abdominal ultrasound examination for tarry stool. Physical examination demonstrated erosions and tense bullae on the conjunctivae, tongue, and lips (Figure 1, a,b), as well as erosive erythematous skin lesions on the nape, right index finger, both legs, and symmetric lesions on the gluteal region (Figure 1, c). His body weight was 86 kg. Laboratory examinations showed slight liver dysfunction and elevation of C-reactive protein levels. Histopathologic examination of the skin lesions demonstrated subepidermal blisters with lymphocytic and eosinophilic infiltrates (Figure 1, d,e). Direct immunofluorescence (IF) revealed linear deposits of IgG and C3, but not IgA, along the basement membrane zone (BMZ) (Figure 1, f,g). An IgG subclass study showed IgG1 and IgG4 deposits. Indirect IF on normal human skin revealed weak positivity for IgA anti-keratinocyte cell surface antibodies and IgG anti-BMZ antibodies, which were bound to the dermal side of 1 mol/L NaCl-split skin (Figure 1, h). IgG immunoblot analyses of both normal human epidermal and dermal extracts showed negative results (including BP230, BP180, 290 kDa type VII collagen, and 200 kDa laminin-γ1). Immunoprecipitation using radio-labeled cultured keratinocyte lysate demonstrated positive reactivity with laminin-332 (Figure 1, i). We established the diagnosis of anti-laminin-332 MMP. We started treatment with oral minocycline (200 mg/day) and niacinamide (900 mg/day) with topical corticosteroids without any effect after 2 weeks of therapy. Administration of oral prednisolone (40 mg/day) with topical corticosteroids and alprostadil ointment on the skin lesions, as well as beclometasone dipropionate powder on the oral lesions resulted in significant improvement of mucocutaneous lesions within 10 days. Although the gastric cancer and liver metastasis initially responded to chemotherapy with fluorouracil and cisplatin, the patient succumbed to multiple organ failure 9 months after the initial visit. Anti-laminin-332 antibodies were originally detected by immunoprecipitation, as in our case. Immunoblotting of purified human laminin-332 have been subsequently developed, which detects the 165/145 kDa α3, 140 kDa ß3, and 105 kDa γ2 subunits of laminin-332 in various patterns (6). Today, the ELISA system uses laminin-332 preparations as adjunct diagnostic tools in MMP (7). Occasionally, a wide spectrum of autoantibodies is detected in MMP, for example, MMP with IgG antibodies to both BP180 and laminin-332, which were considered to be developed via epitope spreading. Detection of circulating IgA autoantibodies against the skin have also been reported in MMP (8). However, the pathogenic significance and mechanisms of coexistence of IgG anti-laminin-332 antibodies and IgA anti-keratinocyte cell surface antibodies found in our case are currently unknown. It is generally considered that IgG1 antibodies activate complements and are pathogenic in MMP, while IgG4 antibodies behave as blocking antibodies and are protective. In our case, direct IF revealed IgG1 and IgG4 deposits; the same was reported in a previous case report (9). The pathogenic roles of autoantibodies with different IgG subclasses need to be analyzed in further studies. Conjunctival mucosal lesions in MMP may occur by rubbing of the eyes due to irritation. Blinking subjects the conjunctivae to repeated friction. Vocal cords vibrate during breathing and speaking. The tongue moves while eating and drinking; in particular, the tip of the tongue gets into frequent contact with the inner sides of the incisor teeth. In the present case, characteristic symmetrical skin lesions were seen on the weight-bearing areas of the gluteal region on bony prominences which receive mechanical stresses in the sitting position. These skin lesions were subjected to repeated stretch and pressure stresses, but no ischemic changes were observed, such as decubitus ulcers. Therefore, the symmetrical skin lesions in the gluteal region as well as the ocular and oral mucosal lesions seen in our patient might have resulted from the same mechanism of pathogenesis. We reported a case of anti-laminin-332 MMP presenting with symmetrical gluteal skin lesions, probably induced by mechanical stress. MMP primarily affects the mucous membranes, and widespread skin lesions are rare. Our case emphasizes that clinicians need to specifically check for the presence of skin lesions on weight-bearing parts of the body during examination of patients with suspected MMP.

Japanese guidelines for the management of palmoplantar keratoderma.

Palmoplantar keratoderma (PPK) is a collective term for keratinizing disorders in which the main clinical symptom is hyperkeratosis on the palms and soles. To establish the first Japanese guidelines approved by the Japanese Dermatological Association for the management of PPKs, the Committee for the Management of PPKs was founded as part of the Study Group for Rare Intractable Diseases. These guidelines aim to provide current information for the management of PPKs in Japan. Based on evidence, they summarize the clinical manifestations, pathophysiologies, diagnostic criteria, disease severity determination criteria, treatment, and treatment recommendations. Because of the rarity of PPKs, there are only few clinical studies with a high degree of evidence. Therefore, several parts of these guidelines were established based on the opinions of the committee. To further optimize the guidelines, periodic revision in line with new evidence is necessary.

Inhibition of α2-adrenoceptor is renoprotective in 5/6 nephrectomy-induced chronic kidney injury rats.

In the present study, we investigated the renoprotective effects of long-term treatment with yohimbine, an α2-adrenoceptor inhibitor, in a 5/6 nephrectomy-induced chronic kidney disease (CKD) rat model. Male Sprague-Dawley rats were randomly allocated into the following groups: sham-operated, 5/6-nephrectomized (5/6 Nx), 5/6 Nx + low or high dose of yohimbine (0.3 or 3.0 mg/L in drinking water, respectively), and 5/6 Nx + hydralazine (250 mg/L in drinking water). The 5/6 Nx group presented with renal dysfunction, hypertension, noradrenaline overproduction, and histopathological injuries. Blood pressure decreased in both the yohimbine- and hydralazine-treated groups. Treatment with high dose of yohimbine, but not hydralazine, apparently attenuated urinary protein excretion and noradrenaline concentration of renal venous plasma. Renal fibrosis and upregulated fibrosis-related gene expression were suppressed by high dose of yohimbine. Furthermore, yohimbine, but not hydralazine, treatment ameliorated the urinary concentration ability. These findings suggest that long-term yohimbine treatment can be a useful therapeutic option to prevent the progression of CKD.

Clinical practice guide for the treatment of perforating dermatosis.

Perforating dermatoses are a heterogeneous skin disease group defined by transepidermal elimination of various skin materials. Four classical forms of primary perforating dermatosis have been described, where the transepidermal elimination mechanism represents the hallmark of the disease: acquired reactive perforating collagenosis, elastosis perforans serpiginosa, Kyrle's disease and perforating folliculitis. Acquired reactive perforating collagenosis presents with transepidermal elimination of collagen fibers. Elastosis perforans serpiginosum presents with the elimination of elastic fibers. Kyrle's disease presents with transepidermal elimination of abnormal keratin. In perforating folliculitis, it is the content of the follicle. We established diagnostic criteria and severity classification. In addition, the Japanese guideline for treatment of perforating dermatoses was updated using the Medical Information Network Distribution Service (MINDS) methodology. The guideline is based on a systematic published work review completed from 1989 to 2019, and on a formal consensus and approval process. Most medical published work on the treatment is limited to individual case reports and small series of patients. The guideline covers treatment options considered relevant by the expert panel and approved in Japan at the time of the consensus conference.

N,N-Dimethylaminopyrene as a fluorescent affinity mass tag for ligand-binding mode analysis.

Elucidation of the binding mode of protein-ligand interactions provides insights for the design of new pharmacological tools and drug leads. Specific labeling of target proteins with chemical probes, in which the ligands are conjugated with reacting and detecting groups, can establish the binding positions of ligands. Label-assisted laser desorption/ionization mass spectrometry (LA-LDI MS) is a promising detection method to selectively detect labeled molecules. However, previous LDI MS tags, such as nitrogen-substituted pyrenes, had problems with low sensitivity and stability. Here we show 6-N,N-dimethylaminopyrene (dmpy) as a versatile mass tag, which was detected at an amount of 0.1 fmol by LA-LDI MS and applicable for MS/MS analysis. By using ligand-dissociation-type dmpy probes and affinity purification with a polystyrene gel, we demonstrated that dmpy-labeled peptides were predominantly detected by MALDI MS. Our dmpy-probe-labeling method might be highly useful for determining the target biomacromolecules of various ligands and their binding sites.

Yohimbine ameliorates lipopolysaccharide-induced acute kidney injury in rats.

Sepsis-induced acute kidney injury (AKI) is frequently observed in the intensive care unit. We previously revealed that yohimbine, an α2-adrenoceptor antagonist, has protective effects on renal ischemia/reperfusion injury-induced AKI in rats. This study aimed to investigate the renoprotective effect of yohimbine on lipopolysaccharide (LPS)-induced AKI in rats. Male Sprague Dawley rats were randomly divided into the following groups: Sham-operated group, LPS (10 mg/kg, i.p.) and LPS + yohimbine (0.1 or 0.5 mg/kg, i.p.). Kidney functional parameters of blood urea nitrogen (BUN) and plasma creatinine (Pcr) were aggravated in the LPS group. Administration of LPS decreased blood pressure. In addition, kidney injury molecule-1, inducible nitric oxide synthase (iNOS) and expression of various cytokines such as tumour necrosis factor-α, monocyte chemoattractant protein-1, and interleukin (IL)-6 were increased by LPS administration. Yohimbine treatment clearly ameliorated the damaged kidney function and low blood pressure due to LPS. Moreover, yohimbine suppressed cytokine mRNA and iNOS expression enhanced by LPS. However, anti-inflammatory cytokine IL-10 mRNA levels were augmented by yohimbine. Nuclear localization of nuclear factor-kappa B (NF-κB) in the kidney was observed 1 h after injection of LPS in rats. Yohimbine blocked the nuclear localization of NF-κB. In addition, phosphorylation of extracellular signal-regulated kinase (ERK) and cAMP response element binding protein (CREB) were enhanced with yohimbine. These results suggest that yohimbine can prevent LPS-induced sepsis associated with kidney injury by suppressing inflammatory cytokine and iNOS expression as well as enhancing IL-10 expression via ERK/CREB phosphorylation.

Post-treatment with JP-1302 protects against renal ischemia/reperfusion-induced acute kidney injury in rats.

Ischemia/reperfusion injury is the most common cause of acute kidney injury. We previously revealed that pre-treatment with yohimbine or JP-1302 attenuated renal ischemia/reperfusion injury by inhibition of α2C-adrenoceptor antagonist. The aim of the present study is to investigate the effects of post-treatment with JP-1302 on renal ischemia/reperfusion injury in rats. Male Sprague Dawley rats were randomly divided into four groups: sham operation, ischemia/reperfusion, pre-treatment with JP-1302 (3.0 mg/kg) and post-treatment with JP-1302 groups. In ischemia/reperfusion injury, renal functional parameters, such as blood urea nitrogen, plasma creatinine and creatinine clearance, deteriorated after reperfusion. Renal venous norepinephrine concentrations, as well as inflammatory molecules in the kidney increased after reperfusion. Both pre- and post-treatment with JP-1302 improved renal dysfunction, tissue damage, renal venous norepinephrine concentrations and inflammatory molecules expression in the kidney. In conclusion, these results suggest that post-treatment with JP-1302 protects on ischemia/reperfusion-induced acute kidney injury by suppressing cytokine upregulation via α2C-adrenoceptors.

Specific protein-labeling and ligand-binding position analysis with amidopyrene probes as LDI MS tags.

To readily analyze the binding mode of protein-ligand interactions, we developed ligand-bound-type and ligand-dissociation-type probes having 6-amidopyrene (apy) as a detecting group. Matrix- and label-assisted laser desorption/ionization mass spectrometry (MALDI and LA-LDI MS) analyses and a covalent docking simulation using these probes precisely determined the binding position of the ligand biotin on the target protein avidin (RMSD = 0.786 and 0.332 Å). Our apy-probe-labeling method may be useful for determining the unknown ligand-binding sites of various target proteins.

IL-17A induces heterogeneous macrophages, and it does not alter the effects of lipopolysaccharides on macrophage activation in the skin of mice.

Macrophages are central to inflammatory response and become polarized towards the M1 or M2 states upon activation by immunostimulants. In this study, we investigated the effects of lipopolysaccharides (LPS) and interleukin (IL)-17A on the activation of macrophages in in vivo mouse skin. We examined whether macrophages are activated in the skin of imiquimod (IMQ)-treated mice, a model for IL-17A-induced psoriasis-like skin inflammation, and flaky-tail (Flg ft ) mice, a model for IL-17A-induced chronic atopic dermatitis-like skin inflammation. LPS and IL-17A independently increased the expression levels of iNOS, CX3CR1, CD206, phospho-STAT1 and phospho-STAT3 proteins in the skin of B6 mice, and the effects of LPS was not altered by IL-17A. The expression levels of these proteins were increased in the skin of IMQ-treated and Flg ft mice. IL-17A neutralization increased the expressions of iNOS and phospho-STAT1 in the IMQ-treated skin, but it decreased the expressions of CD206 and phospho-STAT3 proteins in the skin of Flg ft mice, suggesting that macrophages to change from the M2 to the M1 state in the skin of these mice. These results suggest that IL-17A is involved in the activation of macrophages that are in the process of adopting the heterogeneous profiles of both the M1 and M2 states.

Binding position analysis of target proteins with the use of amidopyrene probes as LA-LDI enhancing tags.

Amidopyrene-conjugated compounds can be detected by label-assisted laser desorption/ionization mass spectrometry (LA-LDI MS) without matrixes. When actin, a cytoskeletal protein, was labeled with an excess amount of amidopyrene N-hydroxysuccinate (apy-OSu), eight apy-labeled actin peptides were predominantly detected by LA-LDI MS. Then actin was labeled with an amidopyrene NHS ester of the antitumor marine macrolide aplyronine A (ApA-apy-OSu) to form a 1 : 1 conjugate. The sequence of an apy-labeled peptide was established as A(108)PLNPKANR(116) by MS/MS analysis, in which the NHS ester moiety specifically reacted with the ε-amino group of K113. While the fragmentation at the linker part reduces the detection sensitivity of apy-labeled peptides on LA-LDI MS, our chemical probe method is useful for analyzing the binding modes of various ligands and target biomacromolecules that include multiple and weak interactions.

Inherited ichthyosis: Syndromic forms.

Among diseases that cause ichthyosis as one of the symptoms, there are some diseases that induce abnormalities in organs other than the skin. Of these, diseases with characteristic signs are regarded as syndromes. Although these syndromes are very rare, Netherton syndrome, Sjögren-Larsson syndrome, Conradi-Hünermann-Happle syndrome, Dorfman-Chanarin syndrome, ichthyosis follicularis, atrichia and photophobia (IFAP) syndrome, and Refsum syndrome have been described in texts as representative ones. It is important to know the molecular genetics and pathomechanisms in order to establish an effective therapy and beneficial genetic counseling including a prenatal diagnosis.

6-Amidopyrene as a label-assisted laser desorption/ionization (LA-LDI) enhancing tag: development of photoaffinity pyrene derivative.

Pyrene-conjugated compounds are detected by label-assisted laser desorption/ionization mass spectrometry (LA-LDI MS) without matrixes. We found that 6-amidopyrene derivatives were highly detectable by the LDI MS instrument equipped with a 355 nm laser. In a certain case of a 6-amidopyrene derivative, a molecular ion peak [M](+•) and a characteristic fragment ion peak [M-42](+•) were detected in an amount of only 10 fmol. The latter peak, corresponding to the 6-aminopyrene fragment, might be generated in situ by the removal of ketene (CH2=C=O) from the parent molecule. A photoaffinity amidopyrene derivative of an antitumor macrolide aplyronine A (ApA-PaP) was synthesized, which showed potent cytotoxicity and actin-depolymerizing activity. In an LDI MS analysis of the MeOH- and water-adducts of ApA-PaP, oxime N-O bonds as well as amidopyrene N-acetyl moieties were preferentially cleaved, and their internal structures were confirmed by MS/MS analysis. Amidopyrene moiety might enhance fragmentation and stabilize the cleaved fragments by intramolecular or intermolecular weak interactions including hydrogen bonding. Our chemical probe methods might contribute to a detailed analysis of binding modes between various ligands and target biomacromolecules that include multiple and weak interactions.