Education: Ph.D. University of Colorado, Medical Center, 1957 (Microbiology/Biophysics).

Research Interests: Animal virology and the interferon system: development of the interferon system in the chicken embryo; interferon inducibility as a phylogenic marker of viruses for analysis of quasispecies populations; peroral use of cloned chicken interferon to control influenza viruses and as an immunoregulator; analysis of influenza virus populations for interferon inducing- and suppressing-particles, and for cell-killing (apoptosis-inducing) activity. Research conducted in a BSL-2+ virus laboratory.

Selected Publications from 123:

Clonogenic Assay of Type A Influenza Viruses Reveals Noninfectious Cell-Killing (Apoptosis-Inducing) Particles. John M. Ngunjiri, Margaret J. Sekellick, and Philip I. Marcus. Journal of Virology 82(6), 2673-2608, 2008.

Time, Travels, and Travails with the Interferon System. Philip I. Marcus. Journal of Interferon & Cytokine Research 27(12):971-983, 2007.

Super-sentinel chickens detect low-pathogenicity influenza virus. P.I. Marcus, T. Girshick, L. van der Heide, and M.J. Sekellick. Emerging Infectious Diseases 13:1608-1610, 2007.

Amelioration of influenza virus pathogenesis in chickens attributed to the enhanced interferon-inducing capacity of a virus with a truncated NS1 gene. A.N. Cauthen, D. E. Swayne, M.J. Sekellick, P.I. Marcus, and D.L. Suarez. Journal of Virology 81:1838-1847, 2007.

Celebrating the 50th anniversary of the discovery of interferon (Editorial). P.I. Marcus. Journal of Interferon & Cytokine Research 27:87-89, 2007.

The Genesis of "Feeder Cells": Concept and Practice. P.I. Marcus. In Vitro Cellular and Developmental Biology (Animal) 42:235-237, 2006.