\documentclass[10pt]{article}

\usepackage{fullpage}
\usepackage{setspace}
\usepackage{parskip}
\usepackage{titlesec}
\usepackage[section]{placeins}
\usepackage{xcolor}
\usepackage{breakcites}
\usepackage{lineno}
\usepackage{hyphenat}





\PassOptionsToPackage{hyphens}{url}
\usepackage[colorlinks = true,
            linkcolor = blue,
            urlcolor  = blue,
            citecolor = blue,
            anchorcolor = blue]{hyperref}
\usepackage{etoolbox}
\makeatletter
\patchcmd\@combinedblfloats{\box\@outputbox}{\unvbox\@outputbox}{}{%
  \errmessage{\noexpand\@combinedblfloats could not be patched}%
}%
\makeatother


\usepackage{natbib}




\renewenvironment{abstract}
  {{\bfseries\noindent{\abstractname}\par\nobreak}\footnotesize}
  {\bigskip}

\titlespacing{\section}{0pt}{*3}{*1}
\titlespacing{\subsection}{0pt}{*2}{*0.5}
\titlespacing{\subsubsection}{0pt}{*1.5}{0pt}


\usepackage{authblk}


\usepackage{graphicx}
\usepackage[space]{grffile}
\usepackage{latexsym}
\usepackage{textcomp}
\usepackage{longtable}
\usepackage{tabulary}
\usepackage{booktabs,array,multirow}
\usepackage{amsfonts,amsmath,amssymb}
\providecommand\citet{\cite}
\providecommand\citep{\cite}
\providecommand\citealt{\cite}
% You can conditionalize code for latexml or normal latex using this.
\newif\iflatexml\latexmlfalse
\providecommand{\tightlist}{\setlength{\itemsep}{0pt}\setlength{\parskip}{0pt}}%

\AtBeginDocument{\DeclareGraphicsExtensions{.pdf,.PDF,.eps,.EPS,.png,.PNG,.tif,.TIF,.jpg,.JPG,.jpeg,.JPEG}}

\usepackage[utf8]{inputenc}
\usepackage[english]{babel}



\usepackage{float}








\begin{document}

\title{Involvement of neuropeptides in pruritus of patients with bullous
pemphigoid: A pilot study}



\author[1]{Yung-Tsu Cho}%
\affil[1]{National Taiwan University Hospital}%


\vspace{-1em}



  
  \date{May 22, 2024}


\begingroup
\let\center\flushleft
\let\endcenter\endflushleft
\maketitle
\endgroup








\sloppy


\textbf{Article category:} Letters to the editor

\textbf{Involvement of neuropeptides in pruritus of patients with
bullous pemphigoid: A pilot study}

\textbf{Short ruuning Title} : Neuropeptides in bullous pemphigoid

Yung-Tsu Cho, M.D

Department of Dermatology, , and of Medicine, .

\textbf{Corresponding Author:}

Yung-Tsu Cho, M.D.

15F,

Department of Dermatology, , and of Medicine, .

TEL: +886-2-2356-2141, FAX: +886-2-2393-4177, E-mail:
yungtsucho@gmail.com

\textbf{Manuscript word count} : 574, \textbf{Table number} :
1;\textbf{Figure number} : 1

\textbf{Funding Source} : None.

\textbf{IRB number} : NTUHREC 201006012R

\textbf{Conflict of Interest} : The author has no conflict of interest.

\textbf{ABBREVIATION}

BP: bullous pemphigoid

CGRP: calcitonin gene-related peptide

CRCP: CGRP receptor component

NK-1R: neurokinin-1 receptor

SP: substance P

\textbf{KEY WORDS}

bullous pemphigoid

calcitonin gene-related peptide

neurokinin-1 receptor

pruritus

neuropeptide

To the Editor,

Bullous pemphigoid (BP) is an autoimmune blistering disease,
characterized by tense blisters and erythematous urticated plaques on
the skin. The disease mainly affects the elderly and usually leads to
intense itchy sensation.\textsuperscript{1} Pruritus in BP is resulted
from the mediators released by innate immunity cells, such as mast cells
and eosinophils, and from the Th2 cytokines, which have been shown
markedly elevated in patients with BP.\textsuperscript{2} Pruritus in
most of BP patients can be relieved by medical treatments. However, in
certain patients, the intensity of pruritus is high and could not be
satisfactorily reduced by systemic anti-histamines and even
immunomodulatory drugs.

In order to further explore other possible mediators of pruritus in BP
patients, we performed a retrospective study to collect the data of BP
patients with different degrees of pruritus. The study was approved by
the research ethics committee (IRB: NTUHREC 201006012R) and the informed
consents were obtained from all the participants. The diagnosis of BP
was confirmed based on the typical clinical and histological
presentations, and positive findings in direct and indirect
immunofluorescence studies. Fifteen BP patients, including 8 females and
7 males, were recruited with an average age of 70 (Table 1). Among them,
6 patients had intractable pruritus which could not be relieved by high
dose of systemic anti-histamines and corticosteroids, while other 9
patients presented with tolerable pruritus.

The baseline levels of serum BP auto-antibodies between the two groups
did not show significant differences (Mann-Whitney U test, \emph{P}value
= 0.380 and 0.898 in anti-BP180 IgG and IgE; \emph{P} value = 0.661 and
0.093 in anti-BP230 IgG and IgE). The amount of tissue mast cells in
specimens of skin biopsies were also similar between the groups
(Chi-square test, \emph{P} value = 0.912). We performed
immunohistochemistry stains to investigate the expressions of substance
P (SP) (, 13839-1-AP), neurokinin-1 receptor (NK-1R) (Novus Biologicals,
, NB100-74469), calcitonin gene-related peptide (CGRP) (, 250602), and
CGRP receptor component (CRCP) (, ab139264) in skin specimens of these
patients (Figure 1). The intensity of IHC stains were classified based
on the area of staining occupying the high power field (HPF): none, 0
point; \textless{} 1/3: 1 point; 1/3 [?] but \textless{} 2/3, 2 points;
2/3 [?], 3 points. BP patients with intractable pruritus showed
significant higher expressions of NK-1R and CGRP comparing to those with
tolerable pruritus (Chi-square test, \emph{P} value = 0.011 and 0.020,
respectively). (Figure 1)

The role of neuropeptides in the formation of pruritus has been
demonstrated in several skin diseases, such as atopic
dermatitis\textsuperscript{3} and psoriasis.\textsuperscript{4} The
involvement of SP and NK-1R in the pruritus of BP patients has also
reported in one previous study.\textsuperscript{5} It shows that most
cells expressing NK-1R in BP patients are eosinophils. In line with this
previous observation, in addition to SP/NK-1R axis, the results of our
study showed that the presence of both NK-1R and CGRP containing nerve
endings in the skin contribute to the intractable pruritus in BP
patients. Other than pruritus, these neuropeptides can also evoke
neurogenic inflammation,\textsuperscript{6} resulting in erythema and
edema, contributing to the formation of these characteristic
presentations of BP patients. These findings may help the clinicians
trying new therapeutic approaches when treating BP patients with
intractable pruritus. However, our study has some limitations, such as a
small sample size, a lack of control group, and a retrospective study
design. A larger prospective study involving a control group is needed
to confirm our results.

\textbf{ACKNOWLEDGEMENT}

None.

\textbf{REFERENCES}

\begin{enumerate}
\tightlist
\item
  Bernard P, Antonicelli F. Bullous pemphigoid: A review of its
  diagnosis, associations and treatment. Am J Clin Dermatol.
  2017;18:513-528.
\item
  Genovese G, Di Zenzo G, Cozzani E, et al. New insights into the
  pathogenesis of bullous pemphigoid: 2019 update. Front Immunol.
  10:1506. doi: 10.3389/fimmu.2019.01506.
\item
  Lonndahl L, Rasul A, Lonne-Rahm S-B, et al. Tacchykinin upregulation
  in atopic dermatitis. Immunopharmacol Immunotoxicol. 2019;41:117-122.
\item
  Amatya B, El-Nour H, Holst M, et al. Expression of tachykinins and
  their receptors in plaque psoriasis with pruritus. Br J Dermatol.
  2011;164:1023-1029.
\item
  Hashimoto T, Kursewicz CD, Fayne RA, et al. Pathophysiologic
  mechanisms of itch in bullous pemphigoid. J Am Acad Dermatol
  2020;83:53-62.
\item
  Choi JE, Di Nardo A. Skin neurogenic inflammation. Semin Immunopathol.
  2018;40:249-259.
\end{enumerate}

\textbf{Table 1 Demographics of patients with bullous pemphigoid}\selectlanguage{english}
\begin{longtable}[]{@{}lllllllllllll@{}}
\toprule
& \textbf{Age} & \textbf{Gender} & \textbf{Pruritus} & \textbf{BP180*} &
\textbf{BP180*} & \textbf{BP230*} & \textbf{BP230*} & \textbf{Intensity
of IHC stains} & \textbf{Intensity of IHC stains} & \textbf{Intensity of
IHC stains} & \textbf{Intensity of IHC stains} & \textbf{Intensity of
IHC stains}\tabularnewline
\midrule
\endhead
& & & & \textbf{IgG} & \textbf{IgE} & \textbf{IgG} & \textbf{IgE} &
\textbf{Mast cells} & \textbf{SP} & \textbf{NK-1R} & \textbf{CGRP} &
\textbf{CRCP}\tabularnewline
\textbf{1} & 58 & F & T & 14.5 & 0.3914 & 43 & 0.4648 & 1 & 1 & 1 & 1 &
1\tabularnewline
\textbf{2} & 75 & M & I & 81.2 & 0.433 & 4.5 & 0.5526 & 2 & 1 & 2 & 2 &
1\tabularnewline
\textbf{3} & 70 & M & I & 136.7 & 0.4428 & 88 & 0.7104 & 2 & 3 & 2 & 3 &
2\tabularnewline
\textbf{4} & 30 & M & T & 60.2 & 0.4063 & 2.4 & 0.5525 & 2 & 1 & 1 & 2 &
1\tabularnewline
\textbf{5} & 79 & F & I & 89.4 & 0.3985 & 34.3 & 0.5918 & 3 & 2 & 2 & 1
& 1\tabularnewline
\textbf{6} & 71 & M & I & 10.7 & 0.3416 & 53.5 & 0.4992 & 2 & 1 & 2 & 2
& 2\tabularnewline
\textbf{7} & 88 & F & T & 114.6 & 0.3104 & 4 & 0.3153 & 2 & 1 & 1 & 1 &
1\tabularnewline
\textbf{8} & 59 & F & T & 68.8 & 0.4013 & 2.2 & 0.2957 & 2 & 2 & 2 & 1 &
1\tabularnewline
\textbf{9} & 82 & M & I & NA & 0.2724 & NA & 0.5533 & 1 & 3 & 3 & 3 &
3\tabularnewline
\textbf{10} & 83 & F & T & 107 & 0.3356 & 2.7 & 0.225 & 3 & 2 & 1 & 2 &
2\tabularnewline
\textbf{11} & 51 & F & I & 84.2 & 0.1449 & 1.3 & 0.247 & 2 & 2 & 2 & 3 &
3\tabularnewline
\textbf{12} & 79 & F & T & 35 & 0.1905 & 58.3 & 0.561 & 2 & 2 & 1 & 1 &
1\tabularnewline
\textbf{13} & 90 & M & T & 14.4 & 0.1759 & 112.1 & 0.4944 & 2 & 1 & 1 &
1 & 1\tabularnewline
\textbf{14} & 78 & F & T & 63.4 & 0.4661 & 4.1 & 0.4321 & 3 & 1 & 2 & 2
& 1\tabularnewline
\textbf{15} & 62 & M & T & NA & NA & NA & NA & 1 & 2 & 1 & 2 &
3\tabularnewline
\bottomrule
\end{longtable}

CGRP: calcitonin gene-related peptide, CRCP: CGRP receptor component, F:
female, I: intractable, IHC: immunohistochemistry, M: male, NA:
non-available, NK-1R: neurokinin-1 receptor, SP: substance P, T:
tolerable

* The levels of IgG antibody were measured in IU/ml as the
manufacturer's protocol, while those of IgE antibody were measured in
O.D. values.

\textbf{FIGURE LEGEND}

\textbf{Figure 1. Immunohistochemistry stains of SP, CGRP, and their
receptors.} Representative pictures (200X) are shown. Comparisons
between the groups are using chi-square tests.\selectlanguage{english}
\begin{figure}[H]
\begin{center}
\includegraphics[width=0.70\columnwidth]{figures/BP-itch-study-figure-reduced/BP-itch-study-figure-reduced}

\end{center}
\end{figure}

\selectlanguage{english}
\FloatBarrier
\end{document}

