SOCS in situ expression in tuberculous lymphadenitis in an endemic area.
BACKGROUND
The immune response to Mycobacterium tuberculosis is complex and multifactorial, the cytokine system being a major factor in M. tuberculosis immunity.


OBJECTIVE
To analyze the immunohistochemical aspects of tuberculous lymph nodes in immunocompetent patients and search for associations between SOCS and cytokine expression in human tuberculous lymphadenitis.


METHODS
Thirteen lymph nodes were assayed by immunohistochemistry for SOCS-1 and 3, STAT-3, RANTES, MIP-1-alpha, ICAM-1, IFN-gamma as well as CD45RO, CD20, CD34, CD68, trypsin and lysozyme. Additionally, the RT in situ PCR was performed for SOCS-1 and 3 mRNA detection.


RESULTS
Decreased MIP-1 alpha expression together with reduced SOCS-3 (p=0.042), lysozyme (p=0.024) and CD45RO (p=0.05) was observed in the TB lymph nodes compared to the control lymph nodes. In conclusion, the lymphadenitis due to M. tuberculosis was associated with a downregulation of memory T cells (CD45RO), activated lysozymes and SOCS-3 compared to controls, which may play a role in the long-term bacterial replication and altered immune modulation characteristic of the disease.
Laboratory of Immunopathology, Instituto Oswaldo Cruz, FIOCRUZ, Rio de Janeiro, Brazil. nicol@ioc.fiocruz.br
A F
AF
Nicol
G J
GJ
Nuovo
J M C
JM
Coelho
V C
VC
Rolla
C
C
Horn
D000293:Adolescent; D000328:Adult; D000368:Aged; D015703:Antigens, CD / Q000378:metabolism; D016207:Cytokines / Q000096:biosynthesis* / Q000276:immunology; D019353:Endemic Diseases; D006801:Humans; D007150:Immunohistochemistry; D008198:Lymph Nodes / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D008875:Middle Aged; D009113:Muramidase / Q000378:metabolism; D009169:Mycobacterium tuberculosis; D012333:RNA, Messenger / Q000276:immunology; D000071222:Suppressor of Cytokine Signaling 1 Protein; D000071223:Suppressor of Cytokine Signaling 3 Protein; D050826:Suppressor of Cytokine Signaling Proteins / Q000096:biosynthesis* / Q000276:immunology; D014357:Trypsin / Q000378:metabolism; D014388:Tuberculosis, Lymph Node / Q000276:immunology / Q000378:metabolism* / Q000473:pathology
D015703:Antigens, CD; D016207:Cytokines; D012333:RNA, Messenger; C108944:SOCS1 protein, human; C106644:SOCS3 protein, human; D000071222:Suppressor of Cytokine Signaling 1 Protein; D000071223:Suppressor of Cytokine Signaling 3 Protein; D050826:Suppressor of Cytokine Signaling Proteins; D009113:Muramidase; D014357:Trypsin