Pathology of AIDS-related lymphadenopathy and its relationship to expression of CD4 + CD25 + regulatory T cells in lymphoid node tissue / 中国医学科学院学报

<p><b>OBJECTIVE</b>To observe the pathology of AIDS-related lymphadenopathy and its relationship to the expression and distribution of CD4 + CD25 + regulatory T cells in lymphoid node tissue.</p><p><b>METHODS</b>Totally 22 biopsy and 13 autopsy lymphoid node tissues from HIV-positive patients were examined under microscopy and pathological staging was performed. Specific marker for CD4 + CD25 + regulatory T cells in lymphoid node tissue was detected with anti-Foxp3 monoclonal antibody by immunohistochemistry.</p><p><b>RESULTS</b>Among all the 35 specimens, 5, 4, 14, and 12 specimens were histopathologically staged from 1 to 4, respectively. FoxP3 were detected in all lymphoid node tissues. The distribution of FoxP3-positive lymphocytes were mainly in intermediate zone of follicle and cortical area in stages 1 and 2. The counts of FoxP3-positive lymphocytes remarkably decreased in stages 3 and 4, following depletion of lymphocytes.</p><p><b>CONCLUSIONS</b>CD4 + CD25 + regulatory T cells exist in lymphoid node tissue of patients with HIV infection. Their amounts decrease or deplete along with the progression of AIDS-related lymphadenopathy.</p>

Lung pathology and pathogenesis of severe acute respiratory syndrome: a report of six full autopsies / 中华病理学杂志

<p><b>OBJECTIVE</b>Severe acute respiratory syndrome (SARS) is an emerging infectious disease that first manifested in humans in November 2002. The SARS-associated coronavirus (SARS-CoV) has been identified as the causal agent, but the pathology and pathogenesis are still not quite clear.</p><p><b>METHODS</b>Post-mortem lung samples from six patients who died from SARS from April to July 2003 were studied by light and electron microscopy, Masson trichromal staining and immunohistochemistry. Evidence of infection with the SARS-CoV was determined by reverse-transcription PCR (RT-PCR) , serological examination and electron microscopy.</p><p><b>RESULTS</b>Four of six patients had serological and RT-PCR evidence of recent infection of SARS-CoV. Morphologic changes are summarized as follows: (1) Diffuse and bilateral lung consolidation was seen in all patients (6/6) with increasing lung weight. (2) Diffuse alveolar damage was universal (6/6) with hyaline membrane formation (6/6), intra-alveolar edema/hemorrhage (6/6), fibrin deposition (6/6), pneumocyte desquamation (6/6). A marked disruption in the integrity of the alveolar epithelium was confirmed by immunostaining for the epithelial marker AE1/AE3 (6/6). (3) Type II pneumocytes, with mild hyperplasia, atypia, cytomegaly with granular amphophilic cytoplasm and intracytoplasmic lipid accumulation (5/6). (4) Giant cells in the alveoli were seen in five of 6 patients (5/6) , most of which were positive for the epithelial marker AE1/AE3 (5/6), but some cells were positive for the macrophage marker CD68(2/6). (5) A pronounced increase of macrophages were seen in the alveoli and the interstitium of the lung (6/6), which was confirmed by histological study and immunohistochemistry. (6) Haemophagocytosis was present in five of the 6 patients(5/6). (7) Lung fibrosis was seen in five patients(5/6), with alveolar septa and interstitium thickening(5/6), intraalveolar organizing exudates (6/6) and pleura thickening (4/6). Proliferation of collagen was confirmed by Masson trichromal staining, most of which was type III collagen by immunostaining. The formation of distinctive fibroblast/myofibroblast foci was seen in five patients (5/6) by light microscopy and immunochemistry. (8) Squamous metaplasia of bronchial mucosa was seen in five patients(5/6). (9) Thrombi was seen in all patients(6/6). (10) Accompanying infection was present in two patients, one was bacteria, the other was fungus. In addition, electron microscopy revealed viral particles in the cytoplasm of alveolar epithelial cells and endothelial cells corresponding to coronavirus.</p><p><b>CONCLUSION</b>Direct injury of SARS-CoV on alveolar epithelium, prominent macrophage infiltration and distinctive fibroblast/myofibroblast proliferation may play major roles in the pathogenesis of SARS.</p>

A pathological study on liver tissues of patients with HIV infection / 中华肝脏病杂志

<p><b>OBJECTIVE</b>To study the pathological changes of the liver tissues of patients with HIV infection.</p><p><b>METHODS</b>14 biopsy and 12 autopsy liver tissues were examined histologically. HIV-1 related antigen of outer membrane protein gp120 and capsid protein p24 were examined with their corresponding monoclonal antibodies by immunohistochemistry.</p><p><b>RESULTS</b>In the biopsy group, cytomegalic virus (CMV) infection was found in one (1/14) case, outer membrane protein gp120 and/or capsid protein p24 antigen were detected in Kupffer cells and in some of the lymphocytes in 11 cases. All the hepatocytes were negative for outer membrane protein gp120 and capsid protein p24 antigens. In the autopsy group, there were 5 (5/12) cases of liver tissues with CMV infection and 5 cases each with mycobacterium and Toxoplasma gondii infection. Capsid protein p24 was detected in liver tissues in 3 cases.</p><p><b>CONCLUSION</b>There is HIV infection in liver tissue of patients with HIV. The rate of opportunistic infections in liver biopsy samples was lower than that in the autopsy liver tissues of patients with HIV.</p>