Gene delivery to the vasculature mediated by low-titre adeno-associated virus serotypes 1 and 5

BACKGROUND

Vascular gene therapy requires safe and efficient gene transfer in vivo. Recombinant adeno-associated virus (AAV) is a promising viral vector but its use in the vasculature has produced conflicting results and serotypes other than AAV2 have not been intensively studied. We investigated the efficiency of alternative AAV serotypes for vascular gene delivery in vitro and in vivo.

METHODS

Vascular cell lines were transduced in vitro with AAV vectors. Rabbit carotid arteries were transduced with AAV1, 2 and 5 encoding enhanced green fluorescent protein (eGFP) ( approximately 1.4 x 10(9) DNAse-resistant particles (drp)). Gene transfer in vivo was assessed at 14 and 28 days. High-titre doses of AAV2 encoding beta-galactosidase in vivo were also studied.

RESULTS

In vitro, transgene expression was not observed in endothelial cells using AAV2 whereas the use of serotypes 1 and 5 resulted in detectable levels of transgene expression. Coronary artery smooth muscle cells (CASMCs) transduced with AAV2 demonstrated higher levels of GFP expression than AAV1 or 5. Transgene expression in vivo was noted using low-titre AAV1 and AAV5 ( approximately 1.4 x 10(9) drp) in the media and adventitia. Only delivery of AAV1eGFP resulted in neointimal formation (3/7 vessels examined), with transgene expression noted in the neointima. Transgene expression with AAV2 was not detected in any layer of the blood vessel wall using low titre ( approximately 10(9) drp). However, high-titre ( approximately 10(11) drp) AAV2 resulted in transduction of cells in the media and adventitia but not the endothelium.

CONCLUSIONS

AAV1 and AAV5 have advantages over AAV2 for vascular gene delivery at low titres.

Characteristics of menopause in three socioeconomic urban groups in Karachi, Pakistan

To determine age, symptoms and treatment choices in Pakistani women with spontaneous menopause, three groups in Karachi were interviewed using a structured questionnaire. The groups consisted of 250 poor slum dwellers, 250 middle class clinic attenders and 150 wives of retired military officers. Interviews were carried out in 1989 and 1990 by members of a team from the Aga Khan University consisting of a gynaecologist, a community health physician and two senior medical students. All interviewees had natural menopause at least 12 months previously. The results showed a mean age of 47 years for menopause in all groups. One in five women were symptomatic in the poorest group but one in two were in the other groups. Treatment was sought by 6% in the poor group, 26% of the middle class group and 38% of the most privileged group. Age at menopause was 4 years earlier than in most reports and fewer women had menopausal symptoms. These urban women may not represent the situation across the country but, as life expectancy in Pakistan is rising (now 56.4 years for women), menopausal problems may increase.