We wish to retract the manuscript titled “Induction of Apoptosis by HIV Infected Monocytic Cells” by Kirk Sperber, Prarthana Beuria, Netai Singha, Irwin Gelman, Patricia Cortes, Houchu Chen, and Thomas Kraus, The Journal of Immunology, 2003, 170: 1566–1578 . The manuscript contains errors in the presentation of data in some of the figures.

In Fig. 2, where we demonstrated the ability of the murine and rabbit Abs to block apoptosis, the FACS histograms 1, 5, and 6 as well as histograms 3 and 4 were mistakenly duplicated. We have repeated these experiments and demonstrate that both the mouse and rabbit Abs block the apoptotic activity of a bacterial supernatant containing FLJ21908. We have localized the site of the pro-apoptotic activity on the protein by making a fusion protein from aa 330 to aa 665 of the FLJ21908 gene and have identified a 6000-Da breakdown product consistent with the molecular mass of the originally described factor. We have also used Flag-tagged fusion proteins to isolate the apoptotic activity to the terminal 150 aa.

In Fig. 6C, demonstrating that FLJ21908 induces apoptosis through caspase 9, the breakdown products of the positive control and the 50% supernatant appear to be the same. We have repeated these experiments using the FLJ21908 fusion protein and Flag-tagged protein containing the last 150 aa and have demonstrated that caspase 9 is activated in the H-9 T cell line and in the SH-SY5Y neuronal cell line.

The gels in Fig. 9 demonstrating caspase 3 and PARP activation after treatment with the FLJ21908 protein appear the same. We have repeated these experiments using different concentrations of the FLJ21908 Flag-tagged protein and demonstrate caspase 3 and PARP activation.

The flow cytometry control data from Fig. 4B demonstrating that FLJ21908 is necessary and sufficient for the induction of apoptosis look the same but are in fact not identical.

Despite these errors, the message of the manuscript remains unchanged. We report the identification of an apoptotic peptide produced by an HIV-infected human macrophage cell line. However, given the errors made in the figures we wish to retract the manuscript.

Kirk Sperber

Prarthana Beuria

Patricia Cortes

Houchu Chen

Mount Sanai School of Medicine

New York, NY

Kirk Sperber

Netai Singha

The Burnham Institute

La Jolla, CA

Kirk Sperber

Irwin Gelman

Roswell Park Cancer Institute

Buffalo, NY

Kirk Sperber

Thomas Kraus

Northwestern University

Chicago, IL