Local tissue irritating effects and adjuvant activities of calcium phosphate...

http://www.sciencedirect.com ^ | 1997 | http://www.sciencedirect.com

[Maelstorm]

a Department of Safety Research on Biologics, National Institute of Infectious Diseases, Gakuen, Musashimurayama, Tokyo 208, Japan

b Department of Bacteriology, Kinki University School of Medicine, Osakasayama, Osaka 589, Japan

c Animal Production and Grassland Division, Japan International Research Center for Agricultural Sciences, Tsukuba, Ibaraki 305, Japan

Received 5 December 1996; Revised 20 January 1997; accepted 21 January 1997. Available online 12 December 1997.

Abstract

Effects of calcium phosphate and aluminium hydroxide adjuvants with different physical properties were examined in guinea pigs for local histopathological reactions, electron-microscopical changes of macrophages and adjuvanticity on total IgG antibody response to subcutaneously administered ovalbumin (OVA) and tetanus toxoid (TT). Calcium phosphate gel (Ca-gel) induced active inflammatory reactions consisting of neutrophils (pseudoeosinophils) and foamy macrophages associated with many multinuclear giant cells for at least 4 weeks. Aluminium hydroxide gel (Al-gel) also elicited granulomatous inflammatory reactions consisting mainly of macrophages with foamy cytoplasm, small lymphocytes and giant cells at the injection sites for up to 8 weeks or longer. Severity of local tissue irritation due to calcium phosphate gel (Ca-gel) was similar to that due to Al-gel except for the duration of the inflammatory reactions. Calcium phosphate suspension (Ca-sus)-induced local reactions completely ceased by the 4th week, while aluminium hydroxide suspension (Al-sus)-induced reactions were seen up to the 8th week. Electron-microscopical observations showed that both Al-gel and Al-sus caused damage of macrophages. The adjuvant activity of Al-gel for OVA or TT was significantly stronger than that of any other adjuvant material, whereas those of Ca-gel and Ca-sus were not seen at a dose of 3 mg calcium phosphate per millitre. Al-sus-TT at a dose of 3 mg aluminium hydroxide per millilitre induced very low levels of antibody. These results suggest that calcium phosphate adjuvant may not be an useful alternative to Al adjuvant.

[Maelstorm]

This is an older article but interesting in that it provides insight into the H1N1 adjuvants.

[Wonder Warthog]

How about a translation into standard English as to what this is about.

[aruanan]

How about a translation into standard English as to what this is about.

In this context, an adjuvant is a substance that increases immune response. So, let's say that if you need 10X of a particular pathogen to provoke an adequate (meaning sufficiently protective) immune response but that if you use an adjuvant you need only 1/10 X of it. This means that you're able to immunize 10 people for the cost of preparing the immunizing agent for one. Think of it as a hamburger helper for vaccines. It's nothing new.

[Right Wing Assault]

Why does that happen?

[facedown]

Think of it as a hamburger helper for vaccines.

LOL!

[facedown]

Why does that happen?

The adjuvant contains an immune system stimulant, or irritant, which causes the system to respond more vigorously than it would otherwise. Thus a smaller amount of the usually precious, i.e. expensive or rare, antigen, such as inactivated polio virus, can be used.

[Right Wing Assault]

Excellent.

[Wonder Warthog]

"In this context, an adjuvant is a substance that increases immune response. So, let's say that if you need 10X of a particular pathogen to provoke an adequate (meaning sufficiently protective) immune response but that if you use an adjuvant you need only 1/10 X of it. This means that you're able to immunize 10 people for the cost of preparing the immunizing agent for one. Think of it as a hamburger helper for vaccines. It's nothing new."

Thanks. I'm reasonably scientifically literate, but this was just a tad too much "medicalese" for me.

Hmmmm.... I wonder if the same effect happens with allergies. That's what I immediately thought of when I read the piece.