McCulley said this at the inauguration of the Defence Reference Laboratory by Mrs Olusola Obada, the Minister of State for Defence, at the Mogadishu Cantonment.
He said the laboratory, which is the first of its kind in the sub-region, was funded from the grant.
"The Reference Laboratory Programme is part of our $500m assistance to Nigeria since 2005 when the partnership began between U.S. Department of Defence and your Ministry of Defence.
"The partnership between U.S. Department of Defence (DOD) and Nigeria's Ministry of Defence (NMOD) through the Walter Reed Programme (WRP-N) and the Emergency Plan Implementation Committee (EPIC) has grown strong," he said.
MCculley said the partnership was evidenced by the commissioning of a world-class Defence Reference Laboratory (DRL).
According to him, the DRL was a critical piece for health care, enabling world-class diagnostic and laboratory monitoring services for military personnel and civilian population living in the surrounding communities.
He said the DRL would continue to grow, improve health care for the community it served and become a centre for excellence in Nigeria and West Africa sub-region.
In her remarks,Obada said the commencement of full activities at the DRL would lead to great improvement in the handling of HIV programmes and ultimately translate to better care for those living with the virus.
Obada, who was represented by Dr. Evelyn Ngige, said the establishment of the DRL was in line with Mr President's Transformation Agenda in the health sector through strengthening of indigenous capabilities and a drastic reduction on dependence of facilities abroad for similar services.
"Expectedly, this facility will promote the health of our troops, thereby ensuring their combat fitness for International Peace Support Operations and internal security challenges, " she said .
The minister commended the U.S. government for the support and urged the professionals that would be making use of the laboratory to justify the confidence reposed in them.
"But the beauty of the programme is that in all the 24 sites where we have in Nigeria where we treat our troops, civilians are also taken care of and the communities near the barracks also benefit from the programme, " she added.
Also speaking, Maj.-Gen. Tahir Umar, the Chairman of Emergency Plan Implementation Committee, said the success of the sites operated by EPIC across the country had led to the need to provide a laboratory that would be able to assure quality control of all programme sites.
Umar said the establishment of the laboratory was made possible through the funding by the U.S. Defense Department and the Ministry of Defence.