istinct Microbial Communities in Dilated Cardiomyopathy Explanted Hearts Are Associated With Different Myocardial Rejection Outcome

Author(s):Show less -

Pereira, Jaqueline de Jesus ^{[1, 2]} ; Ikegami, Renata Nishiyama ^{[1, 2]} ; Kawakami, Joyce Tiyeko ^{[1, 2]} ; Garavelo, Sherrira Menezes ^{[1, 2]} ; Reis, Marcia Martins ^{[1, 2]} ; Palomino, Suely Aparecida Pinheiro ^{[1, 2]} ; Mangini, Sandrigo ^[1] ; Moreno, Camila Rodrigues ^{[1, 2]} ; de Barros, Samar Freschi ^[1] ; Souza, Aline Rodrigues ^{[1, 2]} ; Higuchi, Maria de Lourdes ^{[1, 2]}

Affiliation

^[1] Univ Sao Paulo, Fac Med, Hosp Clin HCFMUSP, Inst Coracao InCor, Sao Paulo - Brazil

^[2] Univ Sao Paulo, Inst Coracao InCor, Dept Patol, Lab Patol Cardiaca, Sao Paulo - Brazil

• Document type: Journal article
• Source: FRONTIERS IN CELLULAR AND INFECTION MICROBIOLOGY; v. 11, NOV 29 2021.
• Web of Science Citations: 0

Abstract

BackgroundIdiopathic dilated cardiomyopathy (IDCM) myocardial inflammation may be associated with external triggering factors such as infectious agents. Here, we searched if moderate/severe heart transplantation rejection is related to the presence of myocardial inflammation in IDCM explanted hearts, associated with microbial communities. MethodReceptor myocardial samples from 18 explanted hearts were separated into groups according to post-transplant outcome: persistent moderate rejection (PMR; n = 6), moderate rejection (MR; n = 7) that regressed after pulse therapy, and no rejection (NR; n = 5)/light intensity rejection. Inflammation was quantified through immunohistochemistry (IHC), and infectious agents were evaluated by IHC, molecular biology, in situ hybridization technique, and transmission electron microscopy (TEM). ResultsNR presented lower numbers of macrophages, as well as B cells (p = 0.0001), and higher HLA class II expression (p <= 0.0001). PMR and MR showed higher levels of Mycoplasma pneumoniae (p = 0.003) and hepatitis B core (p = 0.0009) antigens. NR presented higher levels of parvovirus B19 (PVB19) and human herpes virus 6 (HHV6) and a positive correlation between Borrelia burgdorferi (Bb) and enterovirus genes. Molecular biology demonstrated the presence of M. pneumoniae, Bb, HHV6, and PVB19 genes in all studied groups. TEM revealed structures compatible with the cited microorganisms. ConclusionsThis initial study investigating on infectious agents and inflammation in the IDCM explanted hearts showed that the association between M. pneumoniae and hepatitis B core was associated with a worse outcome after HT, represented by MR and PMR, suggesting that different IDCM microbial communities may be contributing to post-transplant myocardial rejection. (AU)

• FAPESP's process: 15/25786-2 - Identification of infectious agents in post-heart transplant endomyocardial biopsy of patients with idiopathic dilated cardiomyopathy and lymphocytic myocarditis
• Grantee: Jaqueline de Jesus Pereira
• Support Opportunities: Scholarships in Brazil - Master