Organ-specific hematopoietic changes induced by a recombinant human interferon-alpha in mice

Area of Science:

• Immunology
• Hematology
• Pharmacology

Background:

• Interferon-alpha (IFN-alpha) is a cytokine with therapeutic potential in malignancies and HIV-1.
• IFN-alpha exhibits antiviral activity but can cause hematotoxicity and down-regulate myelopoiesis.
• Recombinant hybrid rHuIFN-alpha A/D shows antiviral effects in murine models.

Purpose of the Study:

• To investigate the effects of acute and subchronic exposure to rHuIFN-alpha A/D on hematopoietic and immune parameters in C57Bl/6 mice.
• To analyze dose-dependent toxicity and immunomodulatory effects of IFN-alpha in vivo.

Main Methods:

• Mice were administered rHuIFN-alpha A/D intraperitoneally at varying doses (0, 1000, 10,000, 100,000 units/day) for 1 or 10 consecutive days.
• Hematological parameters (anemia, leukopenia, thrombocytopenia) and immune cell populations (lymphocytes, granulocytes) in bone marrow and spleen were assessed.
• Progenitor cell assays (CFU-G, CFU-M) and lymphocyte proliferation assays were performed.

Main Results:

• Subchronic exposure to IFN-alpha induced anemia, leukopenia, and thrombocytopenia in mice, mirroring human side effects.
• Leukopenia was non-selective, with reduced lymphocytes and increased granulocytes in spleen and bone marrow.
• IFN-alpha suppressed granulocyte progenitors (CFU-G) while stimulating macrophage progenitors (CFU-M).
• Erythroid cell changes in marrow and spleen suggest microenvironmental influence.
• Splenic B and T lymphocyte proliferation was significantly suppressed in a dose-dependent manner.

Conclusions:

• Multiple dose regimens of IFN-alpha are toxic to erythroid and myeloid cells.
• IFN-alpha exhibits immunotoxicity towards splenic B and T lymphocytes.
• The findings highlight the significant hematological and immunological risks associated with IFN-alpha therapy.