Dilated cardiomyopathy alters the expression patterns of CAR and other adenoviral receptors in human heart

Abstract

Gene therapy trials for heart failure have demonstrated the key role of efficient gene transfer in achieving therapeutic efficacy. An attractive approach to improve adenoviral gene transfer is to use alternative virus serotypes with modified tropism. We performed a detailed analysis of cardiac expression of receptors for several adenovirus serotypes with a focus on differential expression of CAR and CD46, as adenoviruses targeting these receptors have been used in various applications. Explanted hearts from patients with DCM and healthy donors were analyzed using Q-RT-PCR, western blot and immunohistochemistry. Q-RT-PCR and Western analyses revealed robust expression of all receptors except CD80 in normal hearts with lower expression levels in DCM. Immunohistochemical analyses demonstrated that CD46 expression was somewhat higher than CAR both in normal and DCM hearts with highest levels of expression in intramyocardial coronary vessels. Total CAR expression was upregulated in DCM. Triple staining on these vessels demonstrated that both CAR and CD46 were confined to the subendothelial layer in normal hearts. The situation was clearly different in DCM, where both CAR and CD46 were expressed by endothelial cells. The induction of expression of CAR and CD46 by endothelial cells in DCM suggests that viruses targeting these receptors could more easily gain entry to heart cells after intravascular administration. This finding thus has potential implications for the development of targeted gene therapy for heart failure.

Intracardiac injection of a capsid-modified Ad5/35 results in decreased heart toxicity when compared to standard Ad5

“…Our previous studies on adenoviral receptor expression in human heart tissue suggested that the native Ad5 capsid configuration would be better suited for cardiac gene transfer than Ad5/35 vectors as CAR had higher levels of expression than CD46 in both normal and dilated cardiomyopathy hearts [19]. As expected, the injection of unmodified Ad5 vector resulted in significantly more efficient transgene expression than administration of hybrid vector Ad5/35 (Figure 3, Figure 4).…”

“…Previous data demonstrate that Ad5/35 hybrid virus is able to efficiently transduce many cell types that are relatively resistant to Ad5 infection, including hematopoietic stem cells, tumor endothelial cells, and several cancer cell types [12-18]. Previously we have reported an analysis of various Ad receptors in both human dilated cardiomyopathy (DCM) hearts and non-DCM hearts demonstrating significant differences in expression patterns of CAR and CD46, with CAR receptor demonstrating higher expression in both DCM and non-DCM hearts [19]. …”

Mast cell–associated alveolar inflammation in patients with atopic uncontrolled asthma

“…A triple staining immunofluorescence protocol 19,20,33,34 was used to visualize both MC TC and MC T populations simultaneously together with their expression of the IgE receptor (FceRI) or surface-bound IgE (see the Immunohistochemical identification of FceRI1 and IgE1 mast cells section in the Online Repository and Table E2). …”

Histochemistry and cell biology: the annual review 2010

“…The studies of Toivonen et al (2010) related to the analysis of expression pattern of receptors for several Adenoviral (Ad) serotypes in normal and dilated cardiomypathy (DCM) hearts. A particular focus was set on the commonly investigated Ad receptors, the coxsackie and adenovirus receptor (CAR) and CD46.…”