The National Institute of Mental Health (NIMH), National Institute on Aging (NIA), National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), National Institute on Drug Abuse (NIDA), National Institute of Biomedical Imaging and Bioengineering (NIBIB), and National Institute on Neurological Disorders and Stroke (NINDS) request research grant applications to study neuroimmune molecules and mechanisms involved in regulating normal and pathological central nervous system (CNS) function. Because the nature and scope of the proposed research will vary from application to application, it is anticipated that the size and duration of each award will also vary. The total amount awarded and the number of awards will depend upon the mechanism numbers, quality, duration, and costs of the applications received. This PA will use the NIH R01, R21, and R03 award mechanisms. Applications may be submitted by domestic or foreign, for-profit or non-profit organizations, public or private institutions, such as universities, colleges, hospitals, and laboratories; units of State and local governments; eligible agencies of the Federal government. Any individual with the skills, knowledge, and resources necessary to carry out the proposed research is invited to work with their institution to develop an application for support. Individuals from underrepresented racial and ethnic groups as well as individuals with disabilities are always encouraged to apply for NIH programs.