Immunohistochemical detection of double-stranded-RNA-dependent protein kinase (p68) with a novel monoclonal antibody TJ4C4. A case report of an AIDS-associated Kaposi's sarcoma treated with alpha-interferon.
Double-stranded RNA (dsRNA)-dependent protein kinase (p68) has been shown to be induced by alpha-interferon (IFN-alpha) in mammalian cells. It binds to dsRNA, and is believed to be a factor in the control of both cellular and viral protein synthesis. This report describes the use of a new monoclonal antibody (MAb) TJ4C4, to monitor levels of p68 in a patient with AIDS-associated Kaposi's sarcoma. Using a novel immunoperoxidase/iron staining method, we examined formalin-fixed, paraffin-embedded biopsies prior to, and 4 months after the initiation of IFN therapy. Immunostaining showed low levels (1+ staining) of p68 in the pretreatment tissue, whereas a marked increase (4+ staining) was noted during interferon treatment. This staining suggests an increased level of intracellular p68 expression. This patient has subsequently remained on IFN-alpha therapy and is alive with no evidence of Kaposi's sarcoma, 6 1/2 years after diagnosis. The use of MAb TJ4C4 will greatly facilitate the study of p68 kinase in clinical tissues, and may provide a way to monitor the effects of IFN therapy.
Haines
G K
GK
Department of Pathology, Northwestern University/VA Lakeside Medical Center, Chicago, Ill.
Ghadge
G D
GD
Combs
S G
SG
Leslie
W
W
Thimmappaya
B
B
Radosevich
J A
JA
D017088:AIDS-Related Opportunistic Infections / Q000150:complications / Q000188:drug therapy / Q000201:enzymology*; D000328:Adult; D000911:Antibodies, Monoclonal; D001706:Biopsy; D006801:Humans; D007124:Immunoenzyme Techniques; D007150:Immunohistochemistry; D016898:Interferon-alpha / Q000627:therapeutic use; D007501:Iron; D008297:Male; D011494:Protein Kinases / Q000032:analysis*; D012514:Sarcoma, Kaposi / Q000150:complications / Q000188:drug therapy / Q000201:enzymology*; D013194:Staining and Labeling / Q000379:methods; D019892:eIF-2 Kinase
D000911:Antibodies, Monoclonal; D016898:Interferon-alpha; D007501:Iron; D011494:Protein Kinases; D019892:eIF-2 Kinase