Chapter 10 Immunology vol.4

Chapter10 今日のメモ☆

Immunology第四回目はImmunodeficiency（免疫不全）に関して。

Immunodeficiency（免疫不全）はprimary [hereditary（遺伝的）or congenital（先天的）]かsecondary [acquired（後天的）]に大別される。

Primary Immunodeficiencies
 - X-linked agammaglobulinemia（X連鎖無ガンマグロブリン血症）
    B cells do not fully mature (serum immunoglobulin levels are low)
    Therapy : human intravenous immunoglobulin (IVIG)

 - Selective IgA dificiency
    low secretory IgA concentration

 - DiGeorge syndrome
    a decrease in total T cell numbers
    Therapy : bone marrow transplantation (in severe case), thymus grafts（胸腺移植）

 - Nezelof syndrome
    lymphopenia（リンパ球減少）, thymic abnormalities

 - Severe combined immunodeficiency disorders (SCIDs)
    deficiencies in T cells & B cells & serum immunoglobulin

and some others...

Secondary immunodeficiencies
 - Cytotoxic drugs
    suppress the production of blood cells in bone marrow (chemotherapy and loss of neutrophils)

 - Leukemias（白血病）, lymphomas（リンパ腫）, myelomas（骨髄腫）
    destruction of the architecture of lymphoid organs（リンパ組織）

 - AIDS (HIV-1, HIV-2)
  Pathogenesis
    retrovirus（レトロウイルス）: entry and uncoating release the viral RNA genome and the associated reverse transcriptase enzyme（逆転写酵素）, which synthesizes a double-stranded DNA copy of the genome.
     * initial infection （初期感染）: first 3 weeks
     * seroconversion（セロコンバージョン：抗体陽性） 3 weeks to 6 months after, asymptomatic infection（無症候感染）
     * reactivated from latency（潜伏期間） : depletion of T_H cells, macrophages produce new virus, APCs are affected and loss of follicular dendritic cells（濾胞樹状細胞）

  Clinical Symptoms
     * persistent generalized lymphadenophathy（リンパ節症）
     * progression of full-blown AIDS may occur 8 years or longer
     * oral candidasis
     * HIV- associated dementia complex
     * opportunistic infections（日和見感染） or plasms（腫瘍;kaposi sarcoma（カポジ肉腫）等）
※ opportunistic infections are the primary cause of death. : P.carinii, Candida, Mycobacterium, herpes, cytomegalovirus etc

  Therapy
     * antiretroviral drugs
        - nucleoside reverse-transcriptase inhibitor
        - nonnucleoside recers-transcriptase inhibitors
        - integrase inhibitors.
     * IFN-α for kaposi sarcoma
     * active vaccine to limit the spread of HIV infection



タイトル
Today's question
- AIDS(エイズ)の問題
Q: Which statement about HIV infection is not correct?
(A) Individuals who become infected with HIV-1 always show overt symptoms shortly after infection.
(B) Seroconversion to positive status for anti-HIV-1 antibodies is the primary criterion for diagnosis f a viral carrier.
(C) The incubation period for the pathogenesis of AIDS is believed to be 8 years or longer after the initial infection with HIV.
(D) CD4+ T cells and macrophages may be able to spread HIV to uninfected C+ cells without releasing any extracellular virus particles






A: (A)
It is not known what percentage of individuals shows overt（明白な） symptoms after initial infection.  Those who do, however, generally show mononucleosis-like symptoms for approximately weeks.  Some individuals display no overt symptoms.